Trial Outcomes & Findings for Study to Assess the Efficacy and Safety of Rilonacept Treatment in Participants With Recurrent Pericarditis (NCT NCT03737110)

NCT ID: NCT03737110

Last Updated: 2023-09-06

Results Overview

Time to pericarditis recurrence (from randomization to 1st recurrence). Kaplan-Meier. Clinical Events Committee (CEC)-confirmed recurrences used for primary analysis. Recurrence defined as recurrence typical pericarditis pain with supportive objective evidence. CEC-adjudicated recurrences defined as:1) Re-appearance/worsening pericarditis pain (1 NRS ≥ 4) AND elevated CRP (≥1.0 mg/dL) on same day/separated by ≤ 7 days OR 2) Re-appearance/worsening pericarditis pain (1 NRS ≥ 4) AND abnormal CRP (\> 0.5 mg/dL) on same day/separated by ≤ 7 days AND 1 supportive evidence OR 3) Re-appearance/worsening pericarditis pain (no NRS ≥ 4) AND elevated CRP (≥ 1.0 mg/dL) not attributable to other causes AND 1 supportive evidence. Supportive evidence: White blood cell count \> upper limit normal, fever \> 38C, pericardial rub, electrocardiogram changes consistent with pericarditis, new/worsening pericardial effusion (echocardiogram), new/worsening pericardial inflammation (magnetic resonance imaging).

• Recruitment status: COMPLETED
• Study phase: PHASE3
• Target enrollment: 86 participants
• Primary outcome timeframe: RW Period (mean 24.8 weeks)
• Results posted on: 2023-09-06

Participant Flow

Participant milestones

Measure	Run-in Period Single-blind rilonacept 320 mg (or 4.4 mg/kg in pediatric participants ≥ 12 and \< 18 years old) subcutaneous (SC), followed by 160 mg (or 2.2 mg/kg in pediatric participants ≥12 and \<18 years old) injections once weekly for 12 weeks. Participants still in the Run-in Period at the time that the Randomized Withdrawal Period has ended (ie, when the prespecified number of primary efficacy endpoint events have occurred) and the Long-Term Extension (LTE) Period is opened will have the option to enter the LTE directly when they have completed the RI period and have met the definition of clinical response or to withdraw from the study.	Randomized Withdrawal Period: Rilonacept Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point numerical rating scale (NRS) and have 1 C-reactive protein (CRP) value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection. Upon completion of the RW period (ie, when the prespecified number of primary efficacy endpoint events has occurred), all participants who did not discontinue study drug have an option to continue treatment with open-label rilonacept in the LTE period or to withdraw from the study.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection. Upon completion of the RW period (ie, when the prespecified number of primary efficacy endpoint events has occurred), all participants who did not discontinue study drug have an option to continue treatment with open-label rilonacept in the LTE period or to withdraw from the study.	Long Term Extension: Non-Randomized Participants who entered the LTE directly from RI after protocol-specified 22 adjudicated pericarditis recurrence events had accrued received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.	Long Term Extension: Randomized, Recurrence (RW) Participants with recurrence as evaluated based on CEC adjudication in Randomization Withdrawal period received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.	Long Term Extension: Randomized, No Recurrence (RW) Participants with no recurrence as evaluated based on CEC adjudication in Randomization Withdrawal period received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.
Run-in (RI) Period STARTED	86	0	0	0	0	0
Run-in (RI) Period Continue to RW Period	61	0	0	0	0	0
Run-in (RI) Period Continue Directly to LTE Period	15	0	0	0	0	0
Run-in (RI) Period COMPLETED	76	0	0	0	0	0
Run-in (RI) Period NOT COMPLETED	10	0	0	0	0	0
Randomized Withdrawal (RW) Period STARTED	0	30	31	0	0	0
Randomized Withdrawal (RW) Period COMPLETED	0	29	30	0	0	0
Randomized Withdrawal (RW) Period NOT COMPLETED	0	1	1	0	0	0
Long-Term Extension (LTE) Period STARTED	0	0	0	15	25	34
Long-Term Extension (LTE) Period COMPLETED	0	0	0	13	24	32
Long-Term Extension (LTE) Period NOT COMPLETED	0	0	0	2	1	2

Reasons for withdrawal

Measure	Run-in Period Single-blind rilonacept 320 mg (or 4.4 mg/kg in pediatric participants ≥ 12 and \< 18 years old) subcutaneous (SC), followed by 160 mg (or 2.2 mg/kg in pediatric participants ≥12 and \<18 years old) injections once weekly for 12 weeks. Participants still in the Run-in Period at the time that the Randomized Withdrawal Period has ended (ie, when the prespecified number of primary efficacy endpoint events have occurred) and the Long-Term Extension (LTE) Period is opened will have the option to enter the LTE directly when they have completed the RI period and have met the definition of clinical response or to withdraw from the study.	Randomized Withdrawal Period: Rilonacept Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point numerical rating scale (NRS) and have 1 C-reactive protein (CRP) value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection. Upon completion of the RW period (ie, when the prespecified number of primary efficacy endpoint events has occurred), all participants who did not discontinue study drug have an option to continue treatment with open-label rilonacept in the LTE period or to withdraw from the study.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection. Upon completion of the RW period (ie, when the prespecified number of primary efficacy endpoint events has occurred), all participants who did not discontinue study drug have an option to continue treatment with open-label rilonacept in the LTE period or to withdraw from the study.	Long Term Extension: Non-Randomized Participants who entered the LTE directly from RI after protocol-specified 22 adjudicated pericarditis recurrence events had accrued received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.	Long Term Extension: Randomized, Recurrence (RW) Participants with recurrence as evaluated based on CEC adjudication in Randomization Withdrawal period received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.	Long Term Extension: Randomized, No Recurrence (RW) Participants with no recurrence as evaluated based on CEC adjudication in Randomization Withdrawal period received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.
Run-in (RI) Period Lack of Efficacy	3	0	0	0	0	0
Run-in (RI) Period Did Not Meet Clinical Response Criteria	3	0	0	0	0	0
Run-in (RI) Period Adverse Event	4	0	0	0	0	0
Randomized Withdrawal (RW) Period Completed, Not Continuing into LTE	0	1	0	0	0	0
Randomized Withdrawal (RW) Period Withdrawal by Subject	0	0	1	0	0	0
Long-Term Extension (LTE) Period Lost to Follow-up	0	0	0	1	0	0
Long-Term Extension (LTE) Period Withdrawal by Subject	0	0	0	1	0	2
Long-Term Extension (LTE) Period Investigator Decision due to Serious Adverse Event	0	0	0	0	1	0

Baseline Characteristics

Study to Assess the Efficacy and Safety of Rilonacept Treatment in Participants With Recurrent Pericarditis

Baseline characteristics by cohort

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Total n=61 Participants Total of all reporting groups
Age, Continuous	48.0 years STANDARD_DEVIATION 15.70 • n=5 Participants	44.8 years STANDARD_DEVIATION 14.47 • n=7 Participants	46.4 years STANDARD_DEVIATION 15.05 • n=5 Participants
Age, Customized 12 to 17 years	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants
Age, Customized 18 to 64 years	24 Participants n=5 Participants	27 Participants n=7 Participants	51 Participants n=5 Participants
Age, Customized 65 to 78 years	5 Participants n=5 Participants	2 Participants n=7 Participants	7 Participants n=5 Participants
Sex: Female, Male Female	16 Participants n=5 Participants	16 Participants n=7 Participants	32 Participants n=5 Participants
Sex: Female, Male Male	14 Participants n=5 Participants	15 Participants n=7 Participants	29 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	30 Participants n=5 Participants	31 Participants n=7 Participants	61 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race/Ethnicity, Customized White	28 Participants n=5 Participants	28 Participants n=7 Participants	56 Participants n=5 Participants
Race/Ethnicity, Customized Black or African American	1 Participants n=5 Participants	3 Participants n=7 Participants	4 Participants n=5 Participants
Race/Ethnicity, Customized Other, Not Specified	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants

PRIMARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: Intent-to-Treat (ITT) Analysis Set: all participants who were randomized in the RW period.

Time to pericarditis recurrence (from randomization to 1st recurrence). Kaplan-Meier. Clinical Events Committee (CEC)-confirmed recurrences used for primary analysis. Recurrence defined as recurrence typical pericarditis pain with supportive objective evidence. CEC-adjudicated recurrences defined as:1) Re-appearance/worsening pericarditis pain (1 NRS ≥ 4) AND elevated CRP (≥1.0 mg/dL) on same day/separated by ≤ 7 days OR 2) Re-appearance/worsening pericarditis pain (1 NRS ≥ 4) AND abnormal CRP (> 0.5 mg/dL) on same day/separated by ≤ 7 days AND 1 supportive evidence OR 3) Re-appearance/worsening pericarditis pain (no NRS ≥ 4) AND elevated CRP (≥ 1.0 mg/dL) not attributable to other causes AND 1 supportive evidence. Supportive evidence: White blood cell count > upper limit normal, fever > 38C, pericardial rub, electrocardiogram changes consistent with pericarditis, new/worsening pericardial effusion (echocardiogram), new/worsening pericardial inflammation (magnetic resonance imaging).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to Pericarditis Recurrence in the RW Period	NA weeks The median was not reached due to low number of participants with an event at data cutoff.	8.6 weeks Interval 4.0 to 11.7	—	—

SECONDARY outcome

Timeframe: RW Period Week 16

Population: ITT Week 16 Analysis Set: All participants randomized at least 16 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Clinical response was defined as a weekly average of daily pericarditis pain on the NRS ≤ 2.0 and C-reactive protein (CRP) level ≤ 0.5 mg/dL, and on monotherapy of randomized study drug at Week 16.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=21 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=20 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Major Secondary Efficacy Endpoint: Percentage of Participants Who Maintained Clinical Response at Week 16 of the RW Period	81.0 percentage of participants Interval 58.1 to 94.6	20.0 percentage of participants Interval 5.7 to 43.7	—	—

SECONDARY outcome

Timeframe: RW Period Week 16

Population: ITT Week 16 Analysis Set: All participants randomized at least 16 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. No or minimal pain was defined as non-missing NRS ≤ 2.

The percentage of days with no or minimal pericarditis pain in the first 16 weeks was calculated for each participant using 16×7 as the denominator. Missing values in pain diary were counted as 0 day with no or minimal pain. Days of using oral rescue therapy or corticosteroid count as 0 day with no or minimal pain. If bailout rilonacept was used, each administration (loading dose or not) was counted as 7 days without qualifying no or minimal pain.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=21 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=20 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Major Secondary Efficacy Endpoint: Percentage of Days With No or Minimal Pericarditis Pain at Week 16 of the RW Period	98.6 percentage of days Standard Error 7.55	47.4 percentage of days Standard Error 7.26	—	—

SECONDARY outcome

Timeframe: RW Period Week 16

Population: ITT Week 16 Analysis Set: All participants randomized at least 16 weeks before data cutoff.

Percentage of participants with no or minimal pericarditis symptoms at Week 16, based on the PGIPS, a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered using a 7-point rating scale ranging from absent (0=no recurrent pericarditis symptoms) to very severe (6=recurrent pericarditis symptoms that cannot be ignored and markedly limits daily activities).

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=21 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=20 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Major Secondary Efficacy Endpoint: Percentage of Participants With Absent or Minimal Pericarditis Symptoms Based on the Patient Global Impression of Pericarditis Severity (PGIPS) at Week 16 of the RW Period	81.0 percentage of participants Interval 58.1 to 94.6	25.0 percentage of participants Interval 8.7 to 49.1	—	—

SECONDARY outcome

Timeframe: RW Period Week 24

Population: ITT Week 24 Analysis Set: All participants randomized at least 24 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Clinical response was defined as a weekly average of daily pericarditis pain on the NRS ≤ 2.0 and C-reactive protein (CRP) level ≤ 0.5 mg/dL, and on monotherapy of randomized study drug at Week 24.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=17 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Who Maintained Clinical Response at Week 24 of the RW Period	76.5 percentage of participants Interval 50.1 to 93.2	20.0 percentage of participants Interval 4.3 to 48.1	—	—

SECONDARY outcome

Timeframe: RW Period Week 8

Population: ITT Week 8 Analysis Set: All participants randomized at least 8 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Clinical response was defined as a weekly average of daily pericarditis pain on the NRS ≤ 2.0 and C-reactive protein (CRP) level ≤ 0.5 mg/dL, and on monotherapy of randomized study drug at Week 8.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=27 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Who Maintained Clinical Response at Week 8 of the RW Period	77.8 percentage of participants Interval 57.7 to 91.4	25.8 percentage of participants Interval 11.9 to 44.6	—	—

SECONDARY outcome

Timeframe: RW Period Week 24

Population: ITT Week 24 Analysis Set: All participants randomized at least 24 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. No or minimal pain was defined as non-missing NRS ≤ 2.

The percentage of days with no or minimal pericarditis pain in the first 24 weeks was calculated for each participant using 24×7 as the denominator. Missing values in pain diary were counted as 0 day with no or minimal pain. Days of using oral rescue therapy or corticosteroid count as 0 day with no or minimal pain. If bailout rilonacept was used, each administration (loading dose or not) was counted as 7 days without qualifying no or minimal pain.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=17 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Days With No or Minimal Pericarditis Pain at Week 24 of the RW Period	100.6 percentage of days Standard Error 8.02	48.7 percentage of days Standard Error 7.64	—	—

SECONDARY outcome

Timeframe: RW Period Week 8

Population: ITT Week 8 Analysis Set: All participants randomized at least 8 weeks before data cutoff.

Participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. No or minimal pain was defined as non-missing NRS ≤ 2.

The percentage of days with no or minimal pericarditis pain in the first 24 weeks was calculated for each participant using 8×7 as the denominator. Missing values in pain diary were counted as 0 day with no or minimal pain. Days of using oral rescue therapy or corticosteroid count as 0 day with no or minimal pain. If bailout rilonacept was used, each administration (loading dose or not) was counted as 7 days without qualifying no or minimal pain.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=27 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Days With No or Minimal Pericarditis Pain at Week 8 of the RW Period	97.9 percentage of days Standard Error 7.64	57.3 percentage of days Standard Error 7.19	—	—

SECONDARY outcome

Timeframe: RW Period Week 24

Population: ITT Week 24 Analysis Set: All participants randomized at least 24 weeks before data cutoff.

Percentage of participants with no or minimal pericarditis symptoms at Week 24, based on the PGIPS, a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered using a 7-point rating scale ranging from absent (0=no recurrent pericarditis symptoms) to very severe (6=recurrent pericarditis symptoms cannot be ignored and markedly limits daily activities).

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=17 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Symptoms at Week 24 of the RW Period Based on the PGIPS	88.2 percentage of participants Interval 63.6 to 98.5	20.0 percentage of participants Interval 4.3 to 48.1	—	—

SECONDARY outcome

Timeframe: RW Period Week 8

Population: ITT Week 8 Analysis Set: All participants randomized at least 8 weeks before data cutoff.

Percentage of participants with no or minimal pericarditis symptoms at Week 16, based on the Patient Global Impression of Pericarditis Severity (PGI-PS). The PGI-PS is a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered, using a 7-point rating scale ranging from absent (no recurrent pericarditis symptoms) to very severe (recurrent pericarditis symptoms cannot be ignored).

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=27 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Symptoms at Week 8 of the RW Period Based on the PGIPS	85.2 percentage of participants Interval 66.3 to 95.8	32.3 percentage of participants Interval 16.7 to 51.4	—	—

SECONDARY outcome

Timeframe: up to 24 weeks in the RW Period

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Pericarditis recurrence is defined as the recurrence of typical pericarditis pain associated with supportive objective evidence of pericarditis. At any time during the RW period, participants who experienced a suspected recurrence of pericarditis symptoms reported to the study site/clinic for a scheduled or unscheduled visit, during which clinical assessments were performed to gather all the necessary diagnostic data to confirm or rule out the presence of pericarditis recurrence. A pericarditis recurrence event adjudication package was then prepared for adjudication by CEC. Kaplan-Meier estimate.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Without Pericarditis Recurrence in the First 24 Weeks of the RW Period	95.7 percentage of participants Interval 72.9 to 99.4	19.9 percentage of participants Interval 6.5 to 38.6	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Participants were asked to select the score that best described their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to Pericarditis Pain ≥ 4 on the NRS in the RW Period	NA weeks Interval 33.1 to Median not reached due to low events.	4.1 weeks Interval 2.9 to 6.6	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Kaplan-Meier estimate.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to CRP Level ≥ 1 mg/dL in the RW Period	NA weeks Median not reached due to low number of participants with CRP ≥ 1 mg/dL.	6.9 weeks Interval 4.0 to 10.1	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Kaplan-Meier estimate. A pericardial rub (also called a pericardial friction rub) is an audible medical sign used in the diagnosis of pericarditis.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to Pericardial Rub in the RW Period	NA weeks Not estimable due to low number of participants with an event.	NA weeks Not estimable due to low number of participants with an event.	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Kaplan-Meier estimate. ST-segment elevation and PR-segment depression are ECG changes in the evolution of acute pericarditis.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to Widespread ST-segment Elevation or PR-segment Depression on Electrocardiogram (ECG) in the RW Period	NA weeks Not estimable due to low number of participants with an event.	NA weeks Not estimable due to low number of participants with an event.	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

Pericardial effusion based on ECHO was evaluated by the central laboratory during the RW period. Kaplan-Meier estimate.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time to New or Worsening Pericardial Effusion on Echocardiography (ECHO) in the RW Period	NA weeks Not estimable due to low number of participants with an event.	NA weeks Not estimable due to low number of participants with an event.	—	—

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24, RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants with a non-missing value at given time point.

Pericardial effusion based on ECHO was evaluated by the central laboratory during the RW period. "None or trivial/physiologic" is considered to be normal. The "RW Worst Post-baseline" category denotes the largest size of pericardial effusion category in which a participant was reported at any time during the RW period (post-baseline).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=30 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · None or Trivial/Physiologic	28 Participants	28 Participants	30 Participants	30 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · Small	1 Participants	1 Participants	1 Participants	1 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · Moderate	1 Participants	1 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · Very Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Baseline · Missing/Not Done	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · None or Trivial/Physiologic	12 Participants	12 Participants	3 Participants	13 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · Small	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · Moderate	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · Very Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Week 24 · Missing/Not Done	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · None or Trivial/Physiologic	28 Participants	28 Participants	14 Participants	20 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · Small	0 Participants	0 Participants	4 Participants	7 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · Moderate	0 Participants	0 Participants	1 Participants	1 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · Very Large	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants in ECHO Pericardial Effusion Size Categories at RW Period Baseline, RW Week 24 and Worst Post-baseline in the RW Period RW Worst Post-baseline · Missing/Not Done	0 Participants	0 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Weeks 4, 8, 12, 16, 20, 24, 32, 40, 48, 56

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants with a non-missing value at given time point.

Estimated from ANCOVA models including treatment arm as fix effect, baseline value, baseline value by treatment interaction, randomization strata as covariates.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=30 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 4	-0.01 mg/dL Standard Error 0.058	-0.05 mg/dL Standard Error 1.112	0.15 mg/dL Standard Error 0.061	1.46 mg/dL Standard Error 0.861
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 8	0.12 mg/dL Standard Error 0.308	0.11 mg/dL Standard Error 0.300	0.45 mg/dL Standard Error 0.331	0.25 mg/dL Standard Error 0.246
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 12	0.04 mg/dL Standard Error 0.034	-0.04 mg/dL Standard Error 0.085	0.03 mg/dL Standard Error 0.043	0.08 mg/dL Standard Error 0.077
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 16	0.40 mg/dL Standard Error 0.148	0.27 mg/dL Standard Error 0.119	0.04 mg/dL Standard Error 0.227	0.18 mg/dL Standard Error 0.109
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 20	-0.04 mg/dL Standard Error 0.048	-0.10 mg/dL Standard Error 0.181	0.10 mg/dL Standard Error 0.083	0.16 mg/dL Standard Error 0.174
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 24	-0.04 mg/dL Standard Error 0.032	-0.05 mg/dL Standard Error 0.047	0.06 mg/dL Standard Error 0.056	0.02 mg/dL Standard Error 0.045
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 32	-0.05 mg/dL Standard Error 0.016	-0.02 mg/dL Standard Error 0.059	NA mg/dL Standard Error NA Not estimable due to statistical analysis system (SAS) algorithms.	0.07 mg/dL Standard Error 0.055
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 40	0.04 mg/dL Standard Error 0.010	0.08 mg/dL Standard Error 0.298	NA mg/dL Standard Error NA Not estimable due to SAS algorithms.	0.74 mg/dL Standard Error 0.290
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 48	0.02 mg/dL Standard Error 0.000	-0.03 mg/dL Standard Error 0.008	—	0.06 mg/dL Standard Error 0.017
Change From RW Period Baseline Over Time in CRP Levels in RW Period Change at RW Week 56	—	—	—	0.00 mg/dL Standard Error NA 1 participant in arm at time point

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Weeks 1-50, 54

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants with a non-missing value at given time point.

Participants were asked to select the score that best described their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Estimated from ANCOVA models including treatment arm as fix effect, baseline value, baseline value by treatment interaction, randomization strata as covariates.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=30 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 10	-0.17 units on a scale Standard Error 0.270	-0.21 units on a scale Standard Error 0.262	1.11 units on a scale Standard Error 0.343	0.62 units on a scale Standard Error 0.240
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 26	0.19 units on a scale Standard Error 0.145	0.16 units on a scale Standard Error 0.127	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.29 units on a scale Standard Error 0.131
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 27	0.23 units on a scale Standard Error 0.193	0.16 units on a scale Standard Error 0.154	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.15 units on a scale Standard Error 0.157
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 1	-0.08 units on a scale Standard Error 0.103	-0.08 units on a scale Standard Error 0.103	0.17 units on a scale Standard Error 0.099	0.17 units on a scale Standard Error 0.099
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 2	-0.21 units on a scale Standard Error 0.237	-0.25 units on a scale Standard Error 0.273	0.57 units on a scale Standard Error 0.231	0.68 units on a scale Standard Error 0.263
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 3	-0.08 units on a scale Standard Error 0.296	-0.15 units on a scale Standard Error 0.330	1.12 units on a scale Standard Error 0.278	1.29 units on a scale Standard Error 0.302
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 4	-0.16 units on a scale Standard Error 0.322	-0.11 units on a scale Standard Error 0.468	1.05 units on a scale Standard Error 0.333	1.84 units on a scale Standard Error 0.428
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 5	-0.16 units on a scale Standard Error 0.314	-0.21 units on a scale Standard Error 0.351	1.27 units on a scale Standard Error 0.332	1.34 units on a scale Standard Error 0.320
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 6	0.22 units on a scale Standard Error 0.296	0.02 units on a scale Standard Error 0.310	0.96 units on a scale Standard Error 0.290	0.84 units on a scale Standard Error 0.265
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 7	0.06 units on a scale Standard Error 0.273	0.12 units on a scale Standard Error 0.248	0.87 units on a scale Standard Error 0.304	0.86 units on a scale Standard Error 0.224
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 8	0.10 units on a scale Standard Error 0.226	0.11 units on a scale Standard Error 0.205	0.77 units on a scale Standard Error 0.253	0.58 units on a scale Standard Error 0.189
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 9	-0.24 units on a scale Standard Error 0.310	0.05 units on a scale Standard Error 0.320	1.45 units on a scale Standard Error 0.402	1.10 units on a scale Standard Error 0.301
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 11	-0.20 units on a scale Standard Error 0.200	-0.16 units on a scale Standard Error 0.272	0.43 units on a scale Standard Error 0.267	0.46 units on a scale Standard Error 0.250
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 12	0.07 units on a scale Standard Error 0.174	-0.03 units on a scale Standard Error 0.248	0.36 units on a scale Standard Error 0.235	0.32 units on a scale Standard Error 0.225
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 13	-0.02 units on a scale Standard Error 0.331	0.06 units on a scale Standard Error 0.256	0.25 units on a scale Standard Error 0.386	0.07 units on a scale Standard Error 0.220
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 14	0.14 units on a scale Standard Error 0.186	0.08 units on a scale Standard Error 0.185	0.24 units on a scale Standard Error 0.262	0.06 units on a scale Standard Error 0.170
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 15	0.32 units on a scale Standard Error 0.109	0.19 units on a scale Standard Error 0.149	-0.08 units on a scale Standard Error 0.235	0.15 units on a scale Standard Error 0.136
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 16	0.12 units on a scale Standard Error 0.110	-0.07 units on a scale Standard Error 0.167	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.09 units on a scale Standard Error 0.153
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 17	0.19 units on a scale Standard Error 0.129	0.01 units on a scale Standard Error 0.183	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.05 units on a scale Standard Error 0.165
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 18	0.13 units on a scale Standard Error 0.149	0.05 units on a scale Standard Error 0.157	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	-0.05 units on a scale Standard Error 0.131
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 19	0.04 units on a scale Standard Error 0.149	-0.05 units on a scale Standard Error 0.167	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	-0.04 units on a scale Standard Error 0.139
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 20	-0.08 units on a scale Standard Error 0.111	-0.22 units on a scale Standard Error 0.228	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.30 units on a scale Standard Error 0.226
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 21	0.04 units on a scale Standard Error 0.156	0.02 units on a scale Standard Error 0.162	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.23 units on a scale Standard Error 0.160
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 22	-0.08 units on a scale Standard Error 0.097	-0.12 units on a scale Standard Error 0.124	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.01 units on a scale Standard Error 0.120
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 23	-0.01 units on a scale Standard Error 0.103	-0.03 units on a scale Standard Error 0.145	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	-0.01 units on a scale Standard Error 0.140
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 24	0.02 units on a scale Standard Error 0.122	-0.04 units on a scale Standard Error 0.138	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.02 units on a scale Standard Error 0.132
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 25	0.12 units on a scale Standard Error 0.122	0.09 units on a scale Standard Error 0.109	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.13 units on a scale Standard Error 0.110
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 28	0.38 units on a scale Standard Error 0.449	0.33 units on a scale Standard Error 0.339	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.18 units on a scale Standard Error 0.340
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 29	0.26 units on a scale Standard Error 0.160	0.29 units on a scale Standard Error 0.233	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.12 units on a scale Standard Error 0.227
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 30	0.25 units on a scale Standard Error 0.296	0.39 units on a scale Standard Error 0.259	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.64 units on a scale Standard Error 0.250
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 31	0.06 units on a scale Standard Error 0.110	0.02 units on a scale Standard Error 0.109	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.33 units on a scale Standard Error 0.105
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 32	0.47 units on a scale Standard Error 0.081	0.20 units on a scale Standard Error 0.141	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.23 units on a scale Standard Error 0.118
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 33	0.62 units on a scale Standard Error 0.016	0.31 units on a scale Standard Error 0.167	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.20 units on a scale Standard Error 0.151
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 34	1.64 units on a scale Standard Error 0.086	0.95 units on a scale Standard Error 0.387	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.27 units on a scale Standard Error 0.329
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 35	0.75 units on a scale Standard Error 0.055	0.62 units on a scale Standard Error 0.347	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.11 units on a scale Standard Error 0.295
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 36	0.25 units on a scale Standard Error 0.093	0.15 units on a scale Standard Error 0.348	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.20 units on a scale Standard Error 0.346
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 37	-0.02 units on a scale Standard Error 0.243	-0.13 units on a scale Standard Error 0.404	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.16 units on a scale Standard Error 0.367
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 38	0.56 units on a scale Standard Error 0.022	0.40 units on a scale Standard Error 0.177	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.04 units on a scale Standard Error 0.162
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 39	0.96 units on a scale Standard Error 0.260	0.55 units on a scale Standard Error 0.578	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.51 units on a scale Standard Error 0.592
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 40	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.17 units on a scale Standard Error 1.253	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.	0.44 units on a scale Standard Error 1.002
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 41	0.92 units on a scale Standard Error 0.293	0.72 units on a scale Standard Error 0.723	—	0.91 units on a scale Standard Error 0.939
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 42	0.77 units on a scale Standard Error 0.488	0.79 units on a scale Standard Error 0.262	—	0.60 units on a scale Standard Error 0.342
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 43	1.03 units on a scale Standard Error 0.619	0.87 units on a scale Standard Error 0.449	—	0.88 units on a scale Standard Error 0.587
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 44	0.84 units on a scale Standard Error 0.553	0.64 units on a scale Standard Error 0.590	—	0.75 units on a scale Standard Error 0.766
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 45	0.77 units on a scale Standard Error 0.567	0.85 units on a scale Standard Error 0.384	—	3.77 units on a scale Standard Error 1.564
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 46	0.18 units on a scale Standard Error 0.680	0.39 units on a scale Standard Error 0.471	—	NA units on a scale Standard Error NA Not estimable due to SAS algorithms.
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 47	0.07 units on a scale Standard Error 0.000	0.16 units on a scale Standard Error 0.261	—	3.10 units on a scale Standard Error 1.070
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 48	0.03 units on a scale Standard Error 0.000	0.32 units on a scale Standard Error 0.273	—	6.18 units on a scale Standard Error 1.490
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 49	-0.50 units on a scale Standard Error 0.000	-0.13 units on a scale Standard Error 0.115	—	5.77 units on a scale Standard Error 0.630
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 50	0.00 units on a scale Standard Error NA 1 participant	0.00 units on a scale Standard Error NA 1 participant	—	—
Change From RW Period Baseline Over Time in Weekly Average of Pericarditis Pain in the RW Period Change at RW Week 54	—	—	—	0.58 units on a scale Standard Error 0.000

SECONDARY outcome

Timeframe: RW Period Weeks 32, 40, 48, 56

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants with a non-missing value at given time point.

The PGIPS, a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered using a 7-point rating scale ranging from absent (0=no recurrent pericarditis symptoms) to very severe (6=recurrent pericarditis symptoms cannot be ignored and markedly limits daily activities).

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=11 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=12 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=2 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=10 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Symptoms Over Time After RW Period Week 24 Based on the PGIPS Week 32	90.9 percentage of participants Interval 58.72 to 99.77	83.3 percentage of participants Interval 51.59 to 97.91	50.0 percentage of participants Interval 1.26 to 98.74	70.0 percentage of participants Interval 34.75 to 93.33
Percentage of Participants With Absent or Minimal Pericarditis Symptoms Over Time After RW Period Week 24 Based on the PGIPS Week 40	60.0 percentage of participants Interval 14.66 to 94.73	66.7 percentage of participants Interval 22.28 to 95.67	100 percentage of participants Interval 2.5 to 100.0	83.3 percentage of participants Interval 35.88 to 99.58
Percentage of Participants With Absent or Minimal Pericarditis Symptoms Over Time After RW Period Week 24 Based on the PGIPS Week 48	100 percentage of participants Interval 15.81 to 100.0	100 percentage of participants Interval 15.81 to 100.0	—	50.0 percentage of participants Interval 1.26 to 98.74
Percentage of Participants With Absent or Minimal Pericarditis Symptoms Over Time After RW Period Week 24 Based on the PGIPS Week 56	—	—	—	100 percentage of participants Interval 2.5 to 100.0

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Weeks 8, 16, 24, 32, 40, 48, 56

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants with a non-missing value at given time point.

The PGA-PA is a single-item, clinician-reported outcome measure that Investigators use to rate their impression of the patient's overall pericarditis disease activity at the time the assessment is completed, using a rating scale ranging from absent to very severe. The Investigator selected the box that best described a participant's pericarditis activity at the time of occurrence of the assessment: Absent, Minimal, Mild, Moderate, Moderately Severe, Severe, Very Severe.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=30 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Baseline	96.7 percentage of participants Interval 82.78 to 99.92	96.7 percentage of participants Interval 82.78 to 99.92	100 percentage of participants Interval 88.78 to 100.0	100 percentage of participants Interval 88.78 to 100.0
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 8	100 percentage of participants Interval 85.18 to 100.0	100 percentage of participants Interval 85.18 to 100.0	71.4 percentage of participants Interval 41.9 to 91.61	85.2 percentage of participants Interval 66.27 to 95.81
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 16	95.0 percentage of participants Interval 75.13 to 99.87	95.0 percentage of participants Interval 75.13 to 99.87	100 percentage of participants Interval 47.82 to 100.0	95.0 percentage of participants Interval 75.13 to 99.87
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 24	100 percentage of participants Interval 78.2 to 100.0	100 percentage of participants Interval 78.2 to 100.0	100 percentage of participants Interval 29.24 to 100.0	100 percentage of participants Interval 76.84 to 100.0
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 32	90.9 percentage of participants Interval 58.72 to 99.77	83.3 percentage of participants Interval 51.59 to 97.91	50.0 percentage of participants Interval 1.26 to 98.74	90.9 percentage of participants Interval 58.72 to 99.77
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 40	66.7 percentage of participants Interval 9.43 to 99.16	75.0 percentage of participants Interval 19.41 to 99.37	100 percentage of participants Interval 2.5 to 100.0	100 percentage of participants Interval 54.07 to 100.0
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 48	50.0 percentage of participants Interval 1.26 to 98.74	50.0 percentage of participants Interval 1.26 to 98.74	—	50.0 percentage of participants Interval 1.26 to 98.74
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the RW Period Based on the Physician Global Assessment of Pericarditis Activity (PGA-PA) Week 56	—	—	—	100 percentage of participants Interval 2.5 to 100.0

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants 18 years and older with a non-missing value at given time point.

The SF-36 determines participants' overall quality of life by assessing 1) limitations in physical functioning due to health problems; 2) limitations in usual role because of physical health problems; 3) bodily pain; 4) general health perceptions; 5) vitality; 6) limitations in social functioning because of physical or emotional problems; 7) limitations in usual role due to emotional problems; and 8) general mental health. Items 1-4 primarily contribute to the physical component summary (PCS) score of the SF-36. Items 5-8 primarily contribute to the mental component summary (MCS) score of the SF-36. Scores on each item are summed and averaged (range: 0=worst to 100=best) with higher scores indicating better health. Increases from baseline indicate improvement.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=14 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline in Short Form-36 (SF-36) Physical and Mental Component Scores at RW Period Week 24 Change at RW Week 24 in PCS	0.427 score on a scale Standard Deviation 5.8566	0.427 score on a scale Standard Deviation 5.8566	0.363 score on a scale Standard Deviation 2.3866	0.354 score on a scale Standard Deviation 2.7169
Change From RW Period Baseline in Short Form-36 (SF-36) Physical and Mental Component Scores at RW Period Week 24 Change at RW Week 24 in MCS	3.081 score on a scale Standard Deviation 11.3204	3.081 score on a scale Standard Deviation 11.3204	-0.050 score on a scale Standard Deviation 2.7318	-0.575 score on a scale Standard Deviation 5.5922

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants 18 years and older with a non-missing value at given time point.

The SF-36 determines participants' overall quality of life by assessing 1) limitations in physical functioning due to health problems; 2) limitations in usual role because of physical health problems; 3) bodily pain; 4) general health perceptions; 5) vitality; 6) limitations in social functioning because of physical or emotional problems; 7) limitations in usual role due to emotional problems; and 8) general mental health. Scores on each item are summed and averaged (range: 0=worst to 100=best) with higher scores indicating better health. Increases from baseline indicate improvement.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=14 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Physical Functioning	2.427 score on a scale Standard Deviation 5.3887	2.427 score on a scale Standard Deviation 5.3887	-0.637 score on a scale Standard Deviation 1.1027	0.273 score on a scale Standard Deviation 4.0332
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Role Physical	2.995 score on a scale Standard Deviation 5.7997	2.995 score on a scale Standard Deviation 5.7997	1.500 score on a scale Standard Deviation 2.5981	1.123 score on a scale Standard Deviation 3.4967
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Bodily Pain	-0.485 score on a scale Standard Deviation 9.7799	-0.485 score on a scale Standard Deviation 9.7799	0.807 score on a scale Standard Deviation 5.2864	0.921 score on a scale Standard Deviation 6.2063
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in General Health	-0.919 score on a scale Standard Deviation 4.9051	-0.919 score on a scale Standard Deviation 4.9051	-1.587 score on a scale Standard Deviation 5.9895	-1.901 score on a scale Standard Deviation 6.8070
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Vitality	3.168 score on a scale Standard Deviation 9.8845	3.168 score on a scale Standard Deviation 9.8845	1.980 score on a scale Standard Deviation 6.8589	0.636 score on a scale Standard Deviation 6.1850
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Social Functioning	0.669 score on a scale Standard Deviation 8.6544	0.669 score on a scale Standard Deviation 8.6544	0.000 score on a scale Standard Deviation 0.0000	-1.791 score on a scale Standard Deviation 4.2209
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Role Emotional	3.251 score on a scale Standard Deviation 10.7297	3.251 score on a scale Standard Deviation 10.7297	0.000 score on a scale Standard Deviation 0.0000	0.249 score on a scale Standard Deviation 7.0264
Change From RW Baseline in SF-36 Individual Scores at RW Period Week 24 Change at RW Week 24 in Mental Health	3.314 score on a scale Standard Deviation 8.5900	3.314 score on a scale Standard Deviation 8.5900	-0.873 score on a scale Standard Deviation 3.9923	-0.187 score on a scale Standard Deviation 6.7646

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants 18 years and older with a non-missing value at given time point.

The SF-6D is calculated based on responses to 11 items on the SF-36, that correspond to 6 domains: physical functioning, role participation (combined role-physical and role-emotional), social functioning, bodily pain, mental health, and vitality. Individual respondents can be classified on any of 4 to 6 levels of functioning or limitations for each of 6 domains, thus allowing a respondent to be classified into any of 18,000 possible unique health states. Using a standard gamble technique, each of these health states were mapped onto the SF-6D index score, which ranges from 0.00 (worst possible health state/death) to 1.00 (best possible health state/perfect health).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=14 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline in the Short Form Health Survey-6 Domains (SF-6D) Utility Index Score at RW Period Week 24	0.0385 score on a scale Standard Deviation 0.10879	0.0385 score on a scale Standard Deviation 0.10879	-0.0027 score on a scale Standard Deviation 0.05705	-0.0005 score on a scale Standard Deviation 0.09871

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants 18 years and older with a non-missing value at given time point.

The EQ-5D-5L is a self-reported health status questionnaire that consists of 6 questions used to calculate a health utility score for use in health economic analysis. There are 2 components to the EQ-5D-5L: a 5-item health state profile that assesses mobility, self-care, usual activities, pain/discomfort, and anxiety/depression used to obtain an Index Utility Score, as well as a visual analogue scale (VAS) that measures health state. Individual and index scores range from 0 to 1, with low scores representing a higher level of dysfunction. The VAS is designed to rate the participant's current health state on a scale from 0 to 100, where 0 represents the worst imaginable health state and 100 represents the best imaginable health state.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=14 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Mobility	-0.1 score on a scale Standard Deviation 0.52	-0.1 score on a scale Standard Deviation 0.52	0.0 score on a scale Standard Deviation 0.00	-0.1 score on a scale Standard Deviation 0.53
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Self-Care	-0.1 score on a scale Standard Deviation 0.26	-0.1 score on a scale Standard Deviation 0.26	0.0 score on a scale Standard Deviation 0.00	0.1 score on a scale Standard Deviation 0.27
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Usual Activities	-0.1 score on a scale Standard Deviation 0.70	-0.1 score on a scale Standard Deviation 0.70	0.0 score on a scale Standard Deviation 0.00	0.1 score on a scale Standard Deviation 0.36
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Pain/Discomfort	0.1 score on a scale Standard Deviation 0.92	0.1 score on a scale Standard Deviation 0.92	0.0 score on a scale Standard Deviation 1.00	0.1 score on a scale Standard Deviation 0.47
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Anxiety/Depression	-0.1 score on a scale Standard Deviation 0.83	-0.1 score on a scale Standard Deviation 0.83	-0.3 score on a scale Standard Deviation 0.58	0.0 score on a scale Standard Deviation 0.55
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in Index Score	0.0033 score on a scale Standard Deviation 0.09812	0.0033 score on a scale Standard Deviation 0.09812	0.0413 score on a scale Standard Deviation 0.15635	0.0029 score on a scale Standard Deviation 0.08592
Change From RW Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value to RW Period Week 24 Change at RW Week 24 in VAS Score	7.5 score on a scale Standard Deviation 17.32	7.5 score on a scale Standard Deviation 17.32	10.0 score on a scale Standard Deviation 10.15	-8.3 score on a scale Standard Deviation 29.07

SECONDARY outcome

Timeframe: RW Period Baseline, RW Period Week 24

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants 18 years and older with a non-missing value at given time point.

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=14 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RW Period Baseline in Insomnia Severity Index (ISI) Total Score at RW Period Week 24	-0.7 score on a scale Standard Deviation 4.75	-0.7 score on a scale Standard Deviation 4.75	-0.3 score on a scale Standard Deviation 3.79	-0.2 score on a scale Standard Deviation 2.99

SECONDARY outcome

Timeframe: RW Period Baseline (BL), RW Period Week (Wk) 24

Population: ITT Week 24 Analysis Set: All participants randomized at least 24 weeks before data cutoff. Participants 18 years or older

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=17 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=17 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=15 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=15 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Subthreshold Insomnia · Wk 24 Clinical Insomnia, Moderate Severity	0 Participants	0 Participants	0 Participants	0 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Moderate Severity · Wk 24 Clinical Insomnia, Severe	0 Participants	0 Participants	—	—
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL No Clinically Significant Insomnia · Wk 24 No Clinically Significant Insomnia	7 Participants	7 Participants	2 Participants	9 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL No Clinically Significant Insomnia · Wk 24 Subthreshold Insomnia	3 Participants	3 Participants	1 Participants	1 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL No Clinically Significant Insomnia · Wk 24 Clinical Insomnia, Moderate Severity	0 Participants	0 Participants	0 Participants	0 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL No Clinically Significant Insomnia · Wk 24 Clinical Insomnia, Severe	0 Participants	0 Participants	0 Participants	0 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL No Clinically Significant Insomnia · Wk 24 Missing	2 Participants	2 Participants	8 Participants	1 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Subthreshold Insomnia · Wk 24 No Clinically Significant Insomnia	2 Participants	2 Participants	0 Participants	2 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Subthreshold Insomnia · Wk 24 Subthreshold Insomnia	1 Participants	1 Participants	0 Participants	2 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Subthreshold Insomnia · Wk 24 Clinical Insomnia, Severe	0 Participants	0 Participants	0 Participants	0 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Subthreshold Insomnia · Wk 24 Missing	0 Participants	0 Participants	4 Participants	0 Participants
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Moderate Severity · Wk 24 No Clinically Significant Insomnia	0 Participants	0 Participants	—	—
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Moderate Severity · Wk 24 Subthreshold Insomnia	2 Participants	2 Participants	—	—
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Moderate Severity · Wk 24 Clinical Insomnia, Moderate Severity	0 Participants	0 Participants	—	—
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Moderate Severity · Wk 24 Missing	0 Participants	0 Participants	—	—
Change in ISI Categories From RW Period Baseline to RW Period Week 24 BL Clinical Insomnia, Severe · Wk 24 No Clinically Significant Insomnia	—	0 Participants	—	—

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

ORT included analgesics, NSAIDs, and/or colchicine. ORT use while waiting for at least 5 days since previous administration of study drug before receiving bailout, or within 5 days before the assessment of pericarditis recurrence, was excluded.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 12 Weeks	0 percentage of participants	61.3 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 4 Weeks	0 percentage of participants	3.2 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 8 Weeks	0 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 12 Weeks	0 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 16 Weeks	3.3 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 20 Weeks	3.3 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : First Use ≤ 24 Weeks	3.3 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period ORT : All Weeks (Including > 24 Weeks in RW Period)	3.3 percentage of participants	6.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 4 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 8 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 12 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 16 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 20 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : First Use ≤ 24 Weeks	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Corticosteroid : All Weeks (Including > 24 Weeks in RW Period)	0 percentage of participants	0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 4 Weeks	0 percentage of participants	29.0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 8 Weeks	0 percentage of participants	48.4 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 16 Weeks	0 percentage of participants	67.7 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 20 Weeks	0 percentage of participants	71.0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : First Use ≤ 24 Weeks	0 percentage of participants	71.0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Bailout : All Weeks (Including > 24 Weeks in RW Period)	3.3 percentage of participants	74.2 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 4 Weeks	0 percentage of participants	32.3 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 8 Weeks	0 percentage of participants	51.6 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 12 Weeks	0 percentage of participants	64.5 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 16 Weeks	3.3 percentage of participants	71.0 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 20 Weeks	3.3 percentage of participants	74.2 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : First Use ≤ 24 Weeks	3.3 percentage of participants	74.2 percentage of participants	—	—
Percentage of Participants Using Oral Rescue Therapy (ORT), Corticosteroid, or Bailout Rilonacept for Pericarditis Every 4 Weeks Cumulatively in the RW Period Total (any of the above) : All Weeks (Including > 24 Weeks in RW Period)	6.7 percentage of participants	77.4 percentage of participants	—	—

SECONDARY outcome

Timeframe: RW Period (up to Week 24)

Population: ITT Analysis Set: all participants who were randomized in the RW period.

ORT included analgesics, NSAIDs, and/or colchicine.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=31 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Using ORT for Pericarditis in the First 24 Weeks of RW Period	3.3 percentage of participants	6.5 percentage of participants	—	—

SECONDARY outcome

Timeframe: RW Period Week 24

Population: ITT Week 24 Analysis Set: All participants randomized at least 24 weeks before data cutoff. Participants in the MRI substudy with nonmissing data.

MRI assessments were performed in a subgroup of participants (MRI substudy) to assess the percentage of participants with:

• Pericardial delayed hyperenhancement
• Myocardial delayed hyperenhancement
• Pericardial effusion

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=6 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=6 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=3 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion on Magnetic Resonance Imaging (MRI) at RW Week 24 Pericardial Delayed Hyperenhancement	66.7 percentage of participants	66.7 percentage of participants	28.6 percentage of participants	57.1 percentage of participants
Percentage of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion on Magnetic Resonance Imaging (MRI) at RW Week 24 Myocardial Delayed Hyperenhancement	0 percentage of participants	0 percentage of participants	0 percentage of participants	0 percentage of participants
Percentage of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion on Magnetic Resonance Imaging (MRI) at RW Week 24 Pericardial Effusion	0 percentage of participants	0 percentage of participants	0 percentage of participants	0 percentage of participants

SECONDARY outcome

Timeframe: RI Period (up to 12 weeks)

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with a baseline NRS measurement \>= 3.

Participants were asked to select the score that best described their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Time to pain response was defined as number of days from first dose to the first day a participant's daily pain NRS was ≤ 2 of the 3 days over which the rolling average daily pain NRS was ≤ 2.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=66 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time From First Dose to Pain Response in the RI Period	5.0 days Interval 4.0 to 6.0	—	—	—

SECONDARY outcome

Timeframe: RI Period (up to 12 weeks)

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with a baseline CRP measurement \>= 0.5 mg/dL.

Time to CRP normalization, defined as CRP ≤ 0.5 mg/dL, was censored at treatment discontinuation, taking prohibited medication, or Week 12, whichever occurred first.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=69 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time From First Dose to CRP Normalization in the RI Period	7.0 days Interval 5.0 to 8.0	—	—	—

SECONDARY outcome

Timeframe: RI Period (up to 12 weeks)

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with background therapies at RI Baseline.

Time to rilonacept monotherapy was defined as the number of weeks from first dose to the first day of achieving monotherapy.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=79 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time From First Dose to Rilonacept Monotherapy in RI Period	7.3 weeks Interval 7.0 to 8.1	—	—	—

SECONDARY outcome

Timeframe: RI Period (up to 12 weeks)

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with baseline measurements of CRP \>0.5 mg/dL and NRS \> 2.

Time to treatment response is defined as time from first dose to the first day of pain response, and CRP ≤ 0.5 mg/dL within 7 days before or after pain response. Treatment response day will be the first day that the above criterion is met. If pain response occurs before CRP ≤ 0.5 mg/dL, each 3-day rolling average of NRS should be ≤ 2.0 from the day of pain response to the day of CRP ≤ 0.5 mg/dL. The response day will be the day of pain response. If CRP ≤0.5 mg/dL occurs before pain response, the response day will also be the day of pain response.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=79 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Time From First Dose to Treatment Response in RI Period	5.0 days Interval 4.0 to 7.0	—	—	—

SECONDARY outcome

Timeframe: RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants achieving treatment response in the RI period.

Participants were asked to select the score that best described their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'. Clinical Response was defined as a weekly average of daily pericarditis pain of ≤ 2.0 on the 11-point NRS and CRP level ≤ 0.5 mg/dL and participants must have been able to stop background SOC pericarditis therapy by Week 10.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=86 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants Achieving Clinical Response at RI Period Week 12 Achieved Clinical Response	84.9 percentage of participants	—	—	—
Percentage of Participants Achieving Clinical Response at RI Period Week 12 Did Not Achieve Clinical Response	15.1 percentage of participants	—	—	—

SECONDARY outcome

Timeframe: RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with a baseline CRP measurement ≥ 0.5 mg/dL.

CRP normalization was defined as CRP ≤ 0.5 mg/dL.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=69 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With CRP Normalization at RI Period Week 12	98.6 percentage of participants	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Weeks 1-12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment at given time period.

Participants were asked to select the score that best described their average level of pericarditis pain over the previous 24 hours using an 11-point numerical rating scale (NRS), where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=86 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period RI Baseline	4.48 score on a scale Standard Deviation 2.510	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 1	-2.31 score on a scale Standard Deviation 2.187	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 2	-3.18 score on a scale Standard Deviation 2.605	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 3	-3.28 score on a scale Standard Deviation 2.547	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 4	-3.51 score on a scale Standard Deviation 2.614	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 5	-3.55 score on a scale Standard Deviation 2.661	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 6	-3.70 score on a scale Standard Deviation 2.615	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 7	-3.81 score on a scale Standard Deviation 2.663	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 8	-3.92 score on a scale Standard Deviation 2.569	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 9	-3.81 score on a scale Standard Deviation 2.727	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 10	-3.83 score on a scale Standard Deviation 2.649	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 11	-4.05 score on a scale Standard Deviation 2.596	—	—	—
Change From Baseline Over Time in Weekly Average of Pericarditis Pain NRS Score in RI Period Change at RI Week 12	-4.00 score on a scale Standard Deviation 2.658	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Day 4, Weeks 1, 2, 4, 6, 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment at given time period.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=85 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From Baseline Over Time in CRP Levels in RI Period RI Baseline	3.72 mg/dL Standard Deviation 5.719	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Day 4	-2.80 mg/dL Standard Deviation 4.582	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Week 1	-3.48 mg/dL Standard Deviation 5.539	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Week 2	-3.55 mg/dL Standard Deviation 5.717	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Week 4	-3.46 mg/dL Standard Deviation 5.809	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Week 6	-3.55 mg/dL Standard Deviation 5.899	—	—	—
Change From Baseline Over Time in CRP Levels in RI Period Change at RI Week 12	-3.60 mg/dL Standard Deviation 5.916	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with ECHO and ECG abnormalities at RI Baseline.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=11 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=6 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=6 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Resolution of Pericarditis-Related ECHO and ECG Abnormalities at Week 12 of the RI Period	63.6 percentage of participants	100 percentage of participants	100 percentage of participants	—

SECONDARY outcome

Timeframe: RI Period (up to Week 12)

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period.

No or minimal pain is defined as non-missing daily NRS ≤ 2, where participants were asked to select the score that best describes their average level of pericarditis pain over the previous 24 hours using an 11-point NRS, where zero (0) indicates 'no pain' and ten (10) indicates 'pain as bad as it could be'.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=86 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Days With No or Minimal Pain in the RI Period While on Treatment	80.66 percentage of days Standard Deviation 21.388	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Weeks 6 and 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment at given time point.

The PGIPS, a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered using a 7-point rating scale ranging from absent (0=no recurrent pericarditis symptoms) to very severe (6=recurrent pericarditis symptoms cannot be ignored and markedly limits daily activities).

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=83 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With No or Minimal Pericarditis Symptoms Over Time in the RI Period, Based on the PGIPS Baseline	18.1 percentage of participants Interval 10.48 to 28.05	—	—	—
Percentage of Participants With No or Minimal Pericarditis Symptoms Over Time in the RI Period, Based on the PGIPS Week 6	89.5 percentage of participants Interval 80.31 to 95.34	—	—	—
Percentage of Participants With No or Minimal Pericarditis Symptoms Over Time in the RI Period, Based on the PGIPS Week 12	92.6 percentage of participants Interval 84.57 to 97.23	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Weeks 6 and 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment at given time point.

The PGA-PA is a single-item, clinician-reported outcome measure that Investigators use to rate their impression of the patient's overall pericarditis disease activity at the time the assessment is completed, using a rating scale ranging from absent to very severe. The Investigator selected the box that best described a participant's pericarditis activity at the time of occurrence of the assessment: Absent, Minimal, Mild, Moderate, Moderately Severe, Severe, Very Severe.

The exact 95% CI is calculated with randomization strata pooled. Participants who had received bailout rilonacept or rescue medication before the time point were considered nonresponders.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=86 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With No or Minimal Pericarditis Activity Over Time in the RI Period, Based on the PGA-PA RI Baseline	10.6 percentage of participants Interval 4.96 to 19.15	—	—	—
Percentage of Participants With No or Minimal Pericarditis Activity Over Time in the RI Period, Based on the PGA-PA RI Week 6	94.8 percentage of participants Interval 87.23 to 98.57	—	—	—
Percentage of Participants With No or Minimal Pericarditis Activity Over Time in the RI Period, Based on the PGA-PA RI Week 12	98.7 percentage of participants Interval 93.06 to 99.97	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment at given time point.

The SF-36 determines participants' overall quality of life by assessing 1) limitations in physical functioning due to health problems; 2) limitations in usual role because of physical health problems; 3) bodily pain; 4) general health perceptions; 5) vitality; 6) limitations in social functioning because of physical or emotional problems; 7) limitations in usual role due to emotional problems; and 8) general mental health. Scores on each item are summed and averaged (range: 0=worst to 100=best) with higher scores indicating better health. Increases from baseline indicate improvement.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=71 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Physical Component Score	13.8 score on a scale Standard Deviation 8.7	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Mental Component Score	9.2 score on a scale Standard Deviation 9.3	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Physical Functioning	10.1 score on a scale Standard Deviation 9.2	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Role-Physical	13.8 score on a scale Standard Deviation 9.4	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Bodily Pain	19.1 score on a scale Standard Deviation 10.3	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 General Health	7.7 score on a scale Standard Deviation 8.2	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Vitality	13.4 score on a scale Standard Deviation 9.9	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Social Functioning	15.1 score on a scale Standard Deviation 10.6	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Role-Emotional	7.7 score on a scale Standard Deviation 10.0	—	—	—
Change From RI Period Baseline in the SF-36 Domain Scores and Physical and Mental Scores to RI Period Week 12 Mental Health	9.6 score on a scale Standard Deviation 9.0	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment.

The SF-6D is calculated based on responses to 11 items on the SF-36, that correspond to 6 domains: physical functioning, role participation (combined role-physical and role-emotional), social functioning, bodily pain, mental health, and vitality. Individual respondents can be classified on any of 4 to 6 levels of functioning or limitations for each of 6 domains, thus allowing a respondent to be classified into any of 18,000 possible unique health states. Using a standard gamble technique, each of these health states were mapped onto the SF-6D index score, which ranges from 0.00 (worst possible health state/death) to 1.00 (best possible health state/perfect health).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=71 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RI Period Baseline in SF-6D Scores at RI Period Week 12	0.1828 score on a scale Standard Deviation 0.12658	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment.

The EQ-5D-5L is a self-reported health status questionnaire that consists of 6 questions used to calculate a health utility score for use in health economic analysis. There are 2 components to the EQ-5D-5L: a 5-item health state profile that assesses mobility, self-care, usual activities, pain/discomfort, and anxiety/depression used to obtain an Index Utility Score, as well as a visual analogue scale (VAS) that measures health state. Individual and index scores range from 0 to 1, with low scores representing a higher level of dysfunction. The VAS is designed to rate the participant's current health state on a scale from 0 to 100, where 0 represents the worst imaginable health state and 100 represents the best imaginable health state.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=74 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Mobility	-0.2 score on a scale Standard Deviation 0.84	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Self-Care	-0.1 score on a scale Standard Deviation 0.57	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Usual Activities	-1.1 score on a scale Standard Deviation 1.16	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Pain/Discomfort	-1.5 score on a scale Standard Deviation 1.18	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Anxiety/Depression	-0.5 score on a scale Standard Deviation 0.90	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 Index Score	0.1626 score on a scale Standard Deviation 0.16814	—	—	—
Change From RI Period Baseline in 5-level EuroQoL-5 Dimensions (EQ-5D-5L) Individual Scores and Index Value at RI Period Week 12 VAS Score	23.0 score on a scale Standard Deviation 23.41	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Week 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants with an assessment.

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=72 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From RI Period Baseline in ISI Total Score at RI Period Week 12	-4.9 score on a scale Standard Deviation 6.31	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline (BL), RI Period Week (Wk) 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants 18 years or older with an assessment.

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=79 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL No Clinically Significant Insomnia · Wk 12 No Clinically Significant Insomnia	23 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL No Clinically Significant Insomnia · Wk 12 Subthreshold Insomnia	1 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL No Clinically Significant Insomnia · Wk 12 Clinical Insomnia, Moderate Severity	1 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL No Clinically Significant Insomnia · Wk 12 Clinical Insomnia, Severe	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL No Clinically Significant Insomnia · Wk 12 Missing	1 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Subthreshold Insomnia · Wk 12 No Clinically Significant Insomnia	18 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Subthreshold Insomnia · Wk 12 Subthreshold Insomnia	7 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Subthreshold Insomnia · Wk 12 Clinical Insomnia, Moderate Severity	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Subthreshold Insomnia · Wk 12 Clinical Insomnia, Severe	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Subthreshold Insomnia · Wk 12 Missing	2 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Moderate Severity · Wk 12 No Clinically Significant Insomnia	7 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Moderate Severity · Wk 12 Subthreshold Insomnia	10 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Moderate Severity · Wk 12 Clinical Insomnia, Moderate Severity	2 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Moderate Severity · Wk 12 Clinical Insomnia, Severe	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Moderate Severity · Wk 12 Missing	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Severe · Wk 12 No Clinically Significant Insomnia	2 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Severe · Wk 12 Subthreshold Insomnia	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Severe · Wk 12 Clinical Insomnia, Moderate Severity	1 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Severe · Wk 12 Clinical Insomnia, Severe	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Clinical Insomnia, Severe · Wk 12 Missing	1 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Missing · Wk 12 No Clinically Significant Insomnia	3 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Missing · Wk 12 Subthreshold Insomnia	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Missing · Wk 12 Clinical Insomnia, Moderate Severity	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Missing · Wk 12 Clinical Insomnia, Severe	0 Participants	—	—	—
Change in ISI Categories From RI Period Baseline to RI Period Week 12 BL Missing · Wk 12 Missing	0 Participants	—	—	—

SECONDARY outcome

Timeframe: RI Period Baseline, RI Period Weeks 4, 8, 10, 12

Population: Run-in Analysis Set: All participants who received at least 1 dose of study drug in the RI period. Participants 18 years or older with an assessment at given time point.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=86 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 10 · Not Receiving Background Pericarditis Medication	71 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Baseline · Not Receiving Background Pericarditis Medication	7 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Baseline · Receiving Background Pericarditis Medication	79 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 4 · Not Receiving Background Pericarditis Medication	15 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 4 · Receiving Background Pericarditis Medication	69 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 8 · Not Receiving Background Pericarditis Medication	49 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 8 · Receiving Background Pericarditis Medication	32 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 10 · Receiving Background Pericarditis Medication	9 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 12 · Not Receiving Background Pericarditis Medication	76 Participants	—	—	—
Number of Participants Who Were Off Background Pericarditis Medication on or Before RI Period Weeks 4, 8, 10, and 12 RI Week 12 · Receiving Background Pericarditis Medication	3 Participants	—	—	—

SECONDARY outcome

Timeframe: LTE Period, through LTE Follow up (up to Week 48)

Population: LTE Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period.

Annualized Recurrence Rate is defined as the number of recurrences in LTE periods for all participants/Sum of participant years in LTE periods for all participants. Participant years in LTE period is defined as the time from 1st dose date of LTE period to the date of End of Study, or data cutoff date, whichever is earlier. The 95% CI was calculated using an exact method with Poisson distribution. Pericarditis recurrence is defined as the recurrence of typical pericarditis pain associated with supportive objective evidence of pericarditis.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Annualized Rate of Pericarditis Recurrence in the Long-Term Extension (LTE) Period Based on Investigator's Assessment (Based on Investigators' Judgement)	0.088 recurrences per participant per year Interval 0.011 to 0.319	0.168 recurrences per participant per year Interval 0.062 to 0.367	0.125 recurrences per participant per year Interval 0.046 to 0.273	0.132 recurrences per participant per year Interval 0.072 to 0.221

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 12, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline Over Time in CRP Levels Change at Week 24	0.03 mg/dL Standard Deviation 0.182	0.17 mg/dL Standard Deviation 0.909	-0.06 mg/dL Standard Deviation 0.269	0.04 mg/dL Standard Deviation 0.579
Change From LTE Baseline Over Time in CRP Levels LTE Baseline	0.18 mg/dL Standard Deviation 0.294	0.21 mg/dL Standard Deviation 0.249	0.16 mg/dL Standard Deviation 0.251	0.18 mg/dL Standard Deviation 0.257
Change From LTE Baseline Over Time in CRP Levels Change at Week 12	0.01 mg/dL Standard Deviation 0.249	0.00 mg/dL Standard Deviation 0.127	-0.06 mg/dL Standard Deviation 0.255	-0.03 mg/dL Standard Deviation 0.219

SECONDARY outcome

Timeframe: LTE Baseline, LTE Month 12, LTE Month 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

Percentage of participants with no or minimal pericarditis symptoms in the LTE Period, based on the PGIPS, a single-item measure of the participant's impression of the overall severity of pericarditis symptoms at the time the questionnaire is administered using a 7-point rating scale ranging from absent (0=no recurrent pericarditis symptoms) to very severe (6=recurrent pericarditis symptoms that cannot be ignored and markedly limits daily activities).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Activity In the LTE Period Based on the PGIPS LTE Baseline	100.0 percentage of participants Interval 78.2 to 100.0	88.0 percentage of participants Interval 68.78 to 97.45	91.2 percentage of participants Interval 76.32 to 98.14	91.9 percentage of participants Interval 83.18 to 96.97
Percentage of Participants With Absent or Minimal Pericarditis Activity In the LTE Period Based on the PGIPS LTE Week 12	93.3 percentage of participants Interval 68.05 to 99.83	95.8 percentage of participants Interval 78.88 to 99.89	100.0 percentage of participants Interval 89.11 to 100.0	97.2 percentage of participants Interval 90.19 to 99.66
Percentage of Participants With Absent or Minimal Pericarditis Activity In the LTE Period Based on the PGIPS LTE Week 24	86.7 percentage of participants Interval 59.54 to 98.34	78.3 percentage of participants Interval 56.3 to 92.54	93.3 percentage of participants Interval 77.93 to 99.18	86.8 percentage of participants Interval 76.36 to 93.77

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 12, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

The PGA-PA is a single-item, clinician-reported outcome measure that Investigators use to rate their impression of the patient's overall pericarditis disease activity at the time the assessment is completed, using a rating scale ranging from absent to very severe. The Investigator selected the box that best described a participant's pericarditis activity at the time of occurrence of the assessment: Absent, Minimal, Mild, Moderate, Moderately Severe, Severe, Very Severe.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the LTE Period Based on the PGA-PA LTE Baseline	100.0 percentage of participants Interval 78.2 to 100.0	92.0 percentage of participants Interval 73.97 to 99.02	94.1 percentage of participants Interval 80.32 to 99.28	94.6 percentage of participants Interval 86.73 to 98.51
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the LTE Period Based on the PGA-PA LTE Week 24	93.3 percentage of participants Interval 68.05 to 99.83	88.0 percentage of participants Interval 68.78 to 97.45	96.8 percentage of participants Interval 83.3 to 99.92	93.0 percentage of participants Interval 84.33 to 97.67
Percentage of Participants With Absent or Minimal Pericarditis Activity Over Time in the LTE Period Based on the PGA-PA LTE Week 12	100.0 percentage of participants Interval 78.2 to 100.0	91.7 percentage of participants Interval 73.0 to 98.97	97.0 percentage of participants Interval 84.24 to 99.92	95.8 percentage of participants Interval 88.3 to 99.13

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

The SF-36 determines participants' overall quality of life by assessing 1) limitations in physical functioning due to health problems; 2) limitations in usual role because of physical health problems; 3) bodily pain; 4) general health perceptions; 5) vitality; 6) limitations in social functioning because of physical or emotional problems; 7) limitations in usual role due to emotional problems; and 8) general mental health. Scores on each item are summed and averaged (range: 0=worst to 100=best) with higher scores indicating better health. Increases from baseline indicate improvement.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=14 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=23 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=29 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=66 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores General Health: Change at LTE Week 24	1.324 score on a scale Standard Deviation 10.1092	0.932 score on a scale Standard Deviation 7.0108	0.762 score on a scale Standard Deviation 6.1724	0.940 score on a scale Standard Deviation 7.3166
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Mental Health: Change at LTE Week 24	2.988 score on a scale Standard Deviation 9.8321	0.455 score on a scale Standard Deviation 8.2976	1.353 score on a scale Standard Deviation 8.2616	1.387 score on a scale Standard Deviation 8.5381
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Physical Functioning: Change at LTE Week 24	2.596 score on a scale Standard Deviation 8.4132	0.125 score on a scale Standard Deviation 6.4017	-0.463 score on a scale Standard Deviation 5.7067	0.391 score on a scale Standard Deviation 6.5919
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Role-Physical: Change at LTE Week 24	-1.443 score on a scale Standard Deviation 6.0141	2.052 score on a scale Standard Deviation 9.8327	-1.627 score on a scale Standard Deviation 6.6000	-0.306 score on a scale Standard Deviation 7.8579
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Bodily Pain: Change at LTE Week 24	3.082 score on a scale Standard Deviation 10.2083	1.140 score on a scale Standard Deviation 9.6306	-0.820 score on a scale Standard Deviation 8.0536	0.690 score on a scale Standard Deviation 9.0827
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Vitality: Change at LTE Week 24	1.910 score on a scale Standard Deviation 8.2069	1.679 score on a scale Standard Deviation 9.3889	-0.307 score on a scale Standard Deviation 6.6591	0.855 score on a scale Standard Deviation 7.9681
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Social Functioning: Change at LTE Week 24	-0.716 score on a scale Standard Deviation 7.8320	0.219 score on a scale Standard Deviation 10.0797	0.172 score on a scale Standard Deviation 6.4927	0.000 score on a scale Standard Deviation 8.0595
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Role-Emotional: Change at LTE Week 24	0.496 score on a scale Standard Deviation 6.3849	0.758 score on a scale Standard Deviation 5.6497	-0.360 score on a scale Standard Deviation 8.0771	0.211 score on a scale Standard Deviation 6.8796
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Physical Score: Change at LTE Week 24	1.210 score on a scale Standard Deviation 6.5951	1.168 score on a scale Standard Deviation 8.0082	-1.079 score on a scale Standard Deviation 6.3170	0.190 score on a scale Standard Deviation 6.9912
Change From LTE Baseline in the SF-36 Domain Scores and Physical and Mental Scores Mental Score: Change at LTE Week 24	1.186 score on a scale Standard Deviation 7.5539	0.596 score on a scale Standard Deviation 6.6219	0.850 score on a scale Standard Deviation 8.8099	0.833 score on a scale Standard Deviation 7.7298

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

The SF-6D is calculated based on responses to 11 items on the SF-36, that correspond to 6 domains: physical functioning, role participation (combined role-physical and role-emotional), social functioning, bodily pain, mental health, and vitality. Individual respondents can be classified on any of 4 to 6 levels of functioning or limitations for each of six domains, thus allowing a respondent to be classified into any of 18,000 possible unique health states. Using a standard gamble technique, each of these health states were mapped onto the SF-6D index score, which ranges from 0.00 (worst possible health state/death) to 1.00 (best possible health state/perfect health).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=14 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=23 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=29 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=66 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in SF-6D Health Utility Index Score	-0.106 score on a scale Standard Deviation 0.4449	0.163 score on a scale Standard Deviation 0.4368	0.003 score on a scale Standard Deviation 0.0781	0.035 score on a scale Standard Deviation 0.3425

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

The EQ-5D-5L is a self-reported health status questionnaire that consists of 6 questions used to calculate a health utility score for use in health economic analysis. There are 2 components to the EQ-5D-5L: a 5-item health state profile that assesses mobility, self-care, usual activities, pain/discomfort, and anxiety/depression used to obtain an Index Utility Score, as well as a visual analogue scale (VAS) that measures health state. Individual and index scores range from 0 to 1, with low scores representing a higher level of dysfunction. The VAS is designed to rate the participant's current health state on a scale from 0 to 100, where 0 represents the worst imaginable health state and 100 represents the best imaginable health state.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=14 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=23 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=30 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=67 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value VAS Score: Change at Week 24	6.2 score on a scale Standard Deviation 25.95	12.6 score on a scale Standard Deviation 27.07	-0.2 score on a scale Standard Deviation 9.48	5.5 score on a scale Standard Deviation 21.19
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Usual Activities: Change at LTE Week 24	-0.1 score on a scale Standard Deviation 1.35	0.0 score on a scale Standard Deviation 0.80	-0.1 score on a scale Standard Deviation 0.45	-0.1 score on a scale Standard Deviation 0.81
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Pain/Discomfort: Change at Week 24	-0.3 score on a scale Standard Deviation 1.20	-0.2 score on a scale Standard Deviation 0.85	0.0 score on a scale Standard Deviation 0.67	-0.1 score on a scale Standard Deviation 0.86
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Anxiety/Depression: Change at Week 24	-0.1 score on a scale Standard Deviation 0.73	0.1 score on a scale Standard Deviation 0.67	0.0 score on a scale Standard Deviation 0.72	0.0 score on a scale Standard Deviation 0.70
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Index Score: Change at Week 24	0.0546 score on a scale Standard Deviation 0.19544	0.0290 score on a scale Standard Deviation 0.10339	-0.0004 score on a scale Standard Deviation 0.10212	0.0212 score on a scale Standard Deviation 0.12704
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Mobility: Change at LTE Week 24	-0.2 score on a scale Standard Deviation 0.70	0.0 score on a scale Standard Deviation 0.77	0.1 score on a scale Standard Deviation 0.48	0.0 score on a scale Standard Deviation 0.64
Change From LTE Baseline in EQ-5D-5L Individual Scores and Index Value Self-Care: Change at LTE Week 24	0.1 score on a scale Standard Deviation 1.00	-0.1 score on a scale Standard Deviation 0.29	0.0 score on a scale Standard Deviation 0.18	0.0 score on a scale Standard Deviation 0.49

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants 18 years or older with an assessment at given time point.

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=12 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=22 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=29 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=63 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in ISI Total Score	-0.3 score on a scale Standard Deviation 1.87	-0.2 score on a scale Standard Deviation 6.87	-1.1 score on a scale Standard Deviation 3.58	-0.1 score on a scale Standard Deviation 0.89

SECONDARY outcome

Timeframe: LTE Baseline (BL), LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants 18 years or older with an assessment at given time point.

Participant's sleep quality was assessed with the ISI survey questionnaire. The ISI is a 7-item survey, with each question having 5 possible answers (none, mild, moderate, severe, or very severe), scored as 0, 1, 2, 3, or 4, respectively. Scores are summed for a total score, which ranges from 0 to 28. Lower scores are considered good, better, or healthy, and increasingly higher scores are considered to indicate greater insomnia.

Clinical interpretation of the total score is as follows:

0 to 7 = no clinically significant insomnia; 8 to 14 = subthreshold insomnia; 15 to 21 = clinical insomnia (moderate severity); 22 to 28 = clinical insomnia (severe).

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=12 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=24 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=32 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=68 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in ISI Categories LTE BL Subthreshold Insomnia · LTE Week 24 No Clinically Significant Insomnia	0 Participants	2 Participants	3 Participants	5 Participants
Change From LTE Baseline in ISI Categories LTE BL No Clinically Significant Insomnia · LTE Week 24 No Clinically Significant Insomnia	9 Participants	11 Participants	18 Participants	38 Participants
Change From LTE Baseline in ISI Categories LTE BL No Clinically Significant Insomnia · LTE Week 24 Subthreshold Insomnia	1 Participants	2 Participants	4 Participants	7 Participants
Change From LTE Baseline in ISI Categories LTE BL No Clinically Significant Insomnia · LTE Week 24 Clinical Insomnia (Moderate Severity)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL No Clinically Significant Insomnia · LTE Week 24 Clinical Insomnia (Severe)	0 Participants	1 Participants	0 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL No Clinically Significant Insomnia · LTE Week 24 Missing	0 Participants	0 Participants	1 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL Subthreshold Insomnia · LTE Week 24 Subthreshold Insomnia	2 Participants	2 Participants	2 Participants	6 Participants
Change From LTE Baseline in ISI Categories LTE BL Subthreshold Insomnia · LTE Week 24 Clinical Insomnia (Moderate Severity)	0 Participants	1 Participants	0 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL Subthreshold Insomnia · LTE Week 24 Clinical Insomnia (Severe)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Subthreshold Insomnia · LTE Week 24 Missing	0 Participants	1 Participants	1 Participants	2 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Moderate Severity) · LTE Week 24 No Clinically Significant Insomnia	0 Participants	1 Participants	1 Participants	2 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Moderate Severity) · LTE Week 24 Subthreshold Insomnia	0 Participants	2 Participants	0 Participants	2 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Moderate Severity) · LTE Week 24 Clinical Insomnia (Moderate Severity)	0 Participants	0 Participants	1 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Moderate Severity) · LTE Week 24 Clinical Insomnia (Severe)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Moderate Severity) · LTE Week 24 Missing	0 Participants	0 Participants	1 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Severe) · LTE Week 24 No Clinically Significant Insomnia	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Severe) · LTE Week 24 Subthreshold Insomnia	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Severe) · LTE Week 24 Clinical Insomnia (Moderate Severity)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Severe) · LTE Week 24 Clinical Insomnia (Severe)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Clinical Insomnia (Severe) · LTE Week 24 Missing	0 Participants	1 Participants	0 Participants	1 Participants
Change From LTE Baseline in ISI Categories LTE BL Missing · LTE Week 24 No Clinically Significant Insomnia	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Missing · LTE Week 24 Subthreshold Insomnia	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Missing · LTE Week 24 Clinical Insomnia (Moderate Severity)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Missing · LTE Week 24 Clinical Insomnia (Severe)	0 Participants	0 Participants	0 Participants	0 Participants
Change From LTE Baseline in ISI Categories LTE BL Missing · LTE Week 24 Missing	0 Participants	0 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: LTE Period, through LTE Follow up (up to Week 24)

Population: This analysis was not done because Standard of Care treatment was not initiated in the LTE period.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants 18 years or older with an assessment at given time point.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=24 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=24 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=63 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in Pericardial Signs in ECHO Missing	3 Participants	2 Participants	0 Participants	5 Participants
Change From LTE Baseline in Pericardial Signs in ECHO No Change	3 Participants	4 Participants	7 Participants	14 Participants
Change From LTE Baseline in Pericardial Signs in ECHO New	0 Participants	0 Participants	1 Participants	1 Participants
Change From LTE Baseline in Pericardial Signs in ECHO Improving	1 Participants	0 Participants	1 Participants	2 Participants
Change From LTE Baseline in Pericardial Signs in ECHO Resolved	0 Participants	1 Participants	1 Participants	2 Participants
Change From LTE Baseline in Pericardial Signs in ECHO Not Applicable	8 Participants	17 Participants	14 Participants	39 Participants

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: Long term extension (LTE) Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants with an assessment at given time point.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in Pericardial Signs in ECG LTE Baseline · Abnormal-Consistent With Pericarditis	0 Participants	1 Participants	1 Participants	2 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Week 24 · Normal	8 Participants	15 Participants	19 Participants	42 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Baseline · Normal	7 Participants	16 Participants	21 Participants	44 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Baseline · Abnormal-Not Consistent With Pericarditis But Clinically Significant	0 Participants	0 Participants	1 Participants	1 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Baseline · Abnormal-Not Consistent With Pericarditis But Not Clinically Significant	8 Participants	8 Participants	11 Participants	27 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Week 24 · Abnormal-Consistent With Pericarditis	0 Participants	1 Participants	1 Participants	2 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Week 24 · Abnormal-Not Consistent With Pericarditis But Clinically Significant	1 Participants	0 Participants	2 Participants	3 Participants
Change From LTE Baseline in Pericardial Signs in ECG LTE Week 24 · Abnormal-Not Consistent With Pericarditis But Not Clinically Significant	6 Participants	9 Participants	9 Participants	24 Participants

SECONDARY outcome

Timeframe: LTE Baseline, LTE Week 24

Population: LTE Analysis Set - Participants in MRI Substudy. The number analyzed on each row pertains to the number of participants with a given baseline status.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=8 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=13 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=16 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=37 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Yes -> Week 24 Yes	2 participants	5 participants	2 participants	9 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Yes -> Week 24 No	1 participants	1 participants	0 participants	2 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Yes -> Week 24 Not Done	1 participants	3 participants	8 participants	12 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline No -> Week 24 Yes	—	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline No -> Week 24 No	—	1 participants	2 participants	3 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline No -> Week 24 Not Done	—	1 participants	2 participants	3 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Missing -> Week 24 Yes	0 participants	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Missing -> Week 24 No	0 participants	1 participants	0 participants	1 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Delayed Hyperenhancement Baseline Missing -> Week 24 Not Done	4 participants	1 participants	2 participants	7 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Yes -> Week 24 Yes	0 participants	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Yes -> Week 24 No	1 participants	0 participants	2 participants	3 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Yes -> Week 24 Not Done	1 participants	2 participants	1 participants	4 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline No -> Week 24 Yes	0 participants	0 participants	1 participants	1 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline No -> Week 24 No	2 participants	6 participants	1 participants	9 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline No -> Week 24 Not Done	0 participants	3 participants	9 participants	12 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Missing -> Week 24 Yes	0 participants	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Missing -> Week 24 No	0 participants	1 participants	0 participants	1 participants
Change From LTE Baseline in Pericardial Signs in MRI Myocardial Delayed Hyperenhancement Baseline Missing -> Week 24 Not Done	4 participants	1 participants	2 participants	7 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Yes -> Week 24 Yes	0 participants	0 participants	—	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Yes -> Week 24 No	1 participants	1 participants	—	2 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Yes -> Week 24 Not Done	0 participants	0 participants	—	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline No -> Week 24 Yes	0 participants	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline No -> Week 24 No	3 participants	6 participants	4 participants	13 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline No -> Week 24 Not Done	0 participants	4 participants	10 participants	14 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Missing -> Week 24 Yes	0 participants	0 participants	0 participants	0 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Missing -> Week 24 No	0 participants	1 participants	0 participants	1 participants
Change From LTE Baseline in Pericardial Signs in MRI Pericardial Effusion Baseline Missing -> Week 24 Not Done	4 participants	1 participants	2 participants	7 participants

SECONDARY outcome

Timeframe: LTE Week 24

Population: Long term extension (LTE) Analysis Set - MRI Substudy: participants in MRI Substudy who consented to LTE period and took at least 1 dose of study drug in the LTE period. Participants 18 years or older with an assessment at given time point.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=8 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=13 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=16 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=37 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Yes · LTE Week 24=Yes	2 Participants	5 Participants	2 Participants	9 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Yes · LTE Week 24=No	1 Participants	1 Participants	0 Participants	2 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Yes · LTE Week 24=Missing	1 Participants	3 Participants	8 Participants	12 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=No · LTE Week 24=Yes	—	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=No · LTE Week 24=No	—	1 Participants	2 Participants	3 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=No · LTE Week 24=Missing	—	1 Participants	2 Participants	3 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Missing · LTE Week 24=Yes	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Missing · LTE Week 24=No	0 Participants	1 Participants	0 Participants	1 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Delayed Hyperenhancement=Missing · LTE Week 24=Missing	4 Participants	1 Participants	2 Participants	7 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Yes · LTE Week 24=Yes	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Yes · LTE Week 24=No	1 Participants	0 Participants	2 Participants	3 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Yes · LTE Week 24=Missing	1 Participants	2 Participants	1 Participants	4 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=No · LTE Week 24=Yes	0 Participants	0 Participants	1 Participants	1 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=No · LTE Week 24=No	2 Participants	6 Participants	1 Participants	9 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=No · LTE Week 24=Missing	0 Participants	3 Participants	9 Participants	12 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Missing · LTE Week 24=Yes	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Missing · LTE Week 24=No	0 Participants	1 Participants	0 Participants	1 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Myocardial Delayed Hyperenhancement=Missing · LTE Week 24=Missing	4 Participants	1 Participants	2 Participants	7 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Yes · LTE Week 24=Yes	0 Participants	0 Participants	—	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Yes · LTE Week 24=No	1 Participants	1 Participants	—	2 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Yes · LTE Week 24=Missing	0 Participants	0 Participants	—	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=No · LTE Week 24=Yes	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=No · LTE Week 24=No	3 Participants	6 Participants	4 Participants	13 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=No · LTE Week 24=Missing	0 Participants	4 Participants	10 Participants	14 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Missing · LTE Week 24=Yes	0 Participants	0 Participants	0 Participants	0 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Missing · LTE Week 24=No	0 Participants	1 Participants	0 Participants	1 Participants
Number of Participants With Pericardial Delayed Hyperenhancement, Myocardial Delayed Hyperenhancement or Pericardial Effusion at LTE Period Week 24 LTE BL: Pericardial Effusion=Missing · LTE Week 24=Missing	4 Participants	1 Participants	2 Participants	7 Participants

SECONDARY outcome

Timeframe: LTE Period, through LTE Follow up (up to Week 48)

Population: LTE Analysis Set: participants who consented to LTE period and took at least 1 dose of study drug in the LTE period.

Annualized Recurrence Rate is defined as number of recurrences in LTE periods for all participants/Sum of participant years in LTE period for all participants. Participant years in LTE period is defined as the time from 1st dose date of LTE period to the date of End of Study, or data cutoff date, whichever is earlier. The 95% CI was calculated using an exact method with Poisson distribution.

Pericarditis recurrence was defined as the recurrence of typical pericarditis pain associated with supportive objective evidence of pericarditis. At any time during the RW period, participants who experienced a suspected recurrence of pericarditis symptoms reported to the study site/clinic for a scheduled or unscheduled visit, during which clinical assessments were performed to gather all the necessary diagnostic data to confirm or rule out the presence of pericarditis recurrence.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=15 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo n=25 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept n=34 Participants Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=74 Participants Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Annualized Rate of Pericarditis Recurrence in LTE Periods Based on Investigator's Assessment	0.088 recurrences per participant per year Interval 0.011 to 0.319	0.168 recurrences per participant per year Interval 0.062 to 0.367	0.125 recurrences per participant per year Interval 0.046 to 0.273	0.132 recurrences per participant per year Interval 0.072 to 0.221

SECONDARY outcome

Timeframe: RW Period (mean 24.8 weeks)

Population: ITT Analysis Set: all participants who were randomized in the RW period. Participants who received rilonacept in the RW period only.

Annualized Recurrence Rate is defined as the number of recurrences in RW period for all participants/Sum of participant years in RW period for all participants. Participant years in RW period is defined as the time from randomization date to the date of EORW or last dose date + 6 weeks, whichever is earlier. The 95% CI was calculated using an exact method with Poisson distribution.

Pericarditis recurrence was defined as the recurrence of typical pericarditis pain associated with supportive objective evidence of pericarditis. At any time during the RW period, participants who experienced a suspected recurrence of pericarditis symptoms reported to the study site/clinic for a scheduled or unscheduled visit, during which clinical assessments were performed to gather all the necessary diagnostic data to confirm or rule out the presence of pericarditis recurrence.

Outcome measures

Measure	Randomized Withdrawal Period: Rilonacept n=30 Participants Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Placebo Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Before Bailout Rilonacept Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.
Annualized Rate of Pericarditis Recurrence in RW Period Based on CEC Adjudication	0.137 recurrences per participant per year Interval 0.017 to 0.494	—	—	—

Adverse Events

Run-in Period

Serious events: 1 serious events

Other events: 55 other events

Deaths: 0 deaths

Randomized Withdrawal Period: Rilonacept Only, Before Bailout Rilonacept

Serious events: 1 serious events

Other events: 18 other events

Deaths: 0 deaths

Randomized Withdrawal Period: Rilonacept, Including Bailout Rilonacept

Serious events: 1 serious events

Other events: 18 other events

Deaths: 0 deaths

Randomized Withdrawal Period: Placebo Only, Before Bailout Rilonacept

Serious events: 1 serious events

Other events: 7 other events

Deaths: 0 deaths

Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept

Serious events: 3 serious events

Other events: 13 other events

Deaths: 0 deaths

Long-Term Extension Period: Overall

Serious events: 6 serious events

Other events: 43 other events

Deaths: 0 deaths

Serious adverse events

Measure	Run-in Period n=86 participants at risk Single-blind rilonacept 320 mg (or 4.4 mg/kg in pediatric participants ≥ 12 and \< 18 years old) subcutaneous (SC), followed by 160 mg (or 2.2 mg/kg in pediatric subjects ≥12 and \<18 years old) injections once weekly for 12 weeks.	Randomized Withdrawal Period: Rilonacept Only, Before Bailout Rilonacept n=30 participants at risk Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Rilonacept, Including Bailout Rilonacept n=30 participants at risk Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.	Randomized Withdrawal Period: Placebo Only, Before Bailout Rilonacept n=31 participants at risk Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 participants at risk Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.	Long-Term Extension Period: Overall n=74 participants at risk Participants received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.
Cardiac disorders Acute myocardial infarction	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Cardiac disorders Aortic valve disease	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Cardiac disorders Aortic valve incompetence	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Cardiac disorders Cardiac flutter	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Cardiac disorders Left ventricular failure	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Cardiac disorders Pericarditis	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Gastrointestinal disorders Ileus	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Pyrexia	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Hepatobiliary disorders Bile duct stone	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Acute endocarditis	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Corona virus infection	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Pneumonia	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Pneumonia viral	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Injury, poisoning and procedural complications Hip fracture	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Squamous cell carcinoma	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Nervous system disorders Cerebrovascular accident	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Nervous system disorders Transient ischaemic attack	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Product Issues Device malfunction	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Respiratory, thoracic and mediastinal disorders Pneumothorax	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.

Other adverse events

Measure	Run-in Period n=86 participants at risk Single-blind rilonacept 320 mg (or 4.4 mg/kg in pediatric participants ≥ 12 and \< 18 years old) subcutaneous (SC), followed by 160 mg (or 2.2 mg/kg in pediatric subjects ≥12 and \<18 years old) injections once weekly for 12 weeks.	Randomized Withdrawal Period: Rilonacept Only, Before Bailout Rilonacept n=30 participants at risk Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly.	Randomized Withdrawal Period: Rilonacept, Including Bailout Rilonacept n=30 participants at risk Double-blind rilonacept 160 mg (or 2.2 mg/kg in pediatric participants ≥ 12 and \< 18 years old) SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.	Randomized Withdrawal Period: Placebo Only, Before Bailout Rilonacept n=31 participants at risk Double-blind placebo SC injections once weekly.	Randomized Withdrawal Period: Placebo, Including Bailout Rilonacept n=31 participants at risk Double-blind placebo SC injections once weekly. Participants with pericarditis recurrence who meet the protocol criteria for bailout rilonacept (report at least 1 day with pericarditis pain ≥4 on the 11-point NRS and have 1 CRP value ≥ 1 mg/dL \[either on the same day or separated by no more than 7 days\]) receive bailout rilonacept (2 open-label injections of 160 mg rilonacept \[or 4.4 mg/kg for pediatric participants\]) irrespective of randomized treatment assignment and as soon as at least 5 days have passed since the last study drug injection.	Long-Term Extension Period: Overall n=74 participants at risk Participants received up to 24 months of open-label rilonacept 160 mg (or 2.2 mg/kg for pediatric participants) SC injections once weekly based on their clinical status and at the discretion of the Investigator.
Gastrointestinal disorders Diarrhoea	5.8% 5/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	5.4% 4/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Fatigue	2.3% 2/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	4.1% 3/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Injection site erythema	20.9% 18/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	20.0% 6/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	23.3% 7/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	4.1% 3/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Injection site pruritus	5.8% 5/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	13.3% 4/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	16.7% 5/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Injection site swelling	5.8% 5/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Non-cardiac chest pain	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	5.4% 4/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
General disorders Pyrexia	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	5.4% 4/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Corona virus infection	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	13.5% 10/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Influenza	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.5% 2/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Nasopharyngitis	7.0% 6/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.8% 5/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Sinusitis	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	2.7% 2/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Infections and infestations Urinary tract infection	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.8% 5/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Investigations Blood Cholesterol Increased	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Investigations C-reactive protein increased	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	4.1% 3/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Investigations High density lipoprotein increased	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Investigations Lipids increased	0.00% 0/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Musculoskeletal and connective tissue disorders Arthralgia	9.3% 8/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.5% 2/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	5.4% 4/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Musculoskeletal and connective tissue disorders Back pain	3.5% 3/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.5% 2/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	5.4% 4/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Musculoskeletal and connective tissue disorders Musculoskeletal chest pain	3.5% 3/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	12.9% 4/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	12.9% 4/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	14.9% 11/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Musculoskeletal and connective tissue disorders Myalgia	10.5% 9/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Musculoskeletal and connective tissue disorders Osteoarthritis	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Nervous system disorders Headache	8.1% 7/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	4.1% 3/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Respiratory, thoracic and mediastinal disorders Cough	5.8% 5/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Respiratory, thoracic and mediastinal disorders Oropharyngeal pain	1.2% 1/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	10.0% 3/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	2.7% 2/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Respiratory, thoracic and mediastinal disorders Sinus congestion	2.3% 2/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	6.7% 2/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	0.00% 0/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	1.4% 1/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.
Vascular disorders Hypertension	2.3% 2/86 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.3% 1/30 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	3.2% 1/31 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.	9.5% 7/74 • All Cause Mortality: From enrollment through end of study; up to 156 weeks. Adverse events (AEs), RI Period: from first dose of study drug to the RW period randomization visit; mean duration 11.61 weeks. AEs, RW Period Rilonacept Only, Before Bailout: from RW period randomization until bailout rilonacept administration; mean duration 24.40 weeks. AEs, RW Period Rilonacept, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration 25.07 weeks. AEs, RW Period Placebo Only, Before Bailout: from RW period randomization to placebo until bailout rilonacept administration; mean duration was 9.88 weeks. RW Period Placebo, Including Bailout Rilonacept: from RW period randomization until LTE rilonacept administration; mean duration was 23.88 weeks. LTE period: from first dose in the LTE period until 6 weeks post last dose; mean treatment duration was 68.13 weeks. Per statistical analysis plan, safety in LTE period was reported overall only.

Additional Information

Clinical Operations Study Director

Kiniksa Pharmaceuticals (UK), Ltd. c/o Kiniksa Pharmaceuticals Corp.

Phone: 1-781-431-9100

Email: studyinfo@kiniksa.com

Results disclosure agreements

• Principal investigator is a sponsor employee Sponsor has the first right to publish information obtained from the trial. After sponsor publishes, PI may publish its own trial results, provided that sponsor may embargo such publication for up to 60 days for purposes of identifying confidential information (other than trial data) that must be removed and up to an additional 120 days to prepare a patent application if there is patentable subject matter in the PI's proposed publication.
• Publication restrictions are in place

Restriction type: OTHER