Trial Outcomes & Findings for A Study to Compare the Response to Treatment With Abatacept vs Adalimumab, on Background Methotrexate, in Adults With Early, Seropositive, and Shared Epitope-positive Rheumatoid Arthritis and an Inadequate Response to Methotrexate (NCT NCT04909801)

NCT ID: NCT04909801

Last Updated: 2025-02-19

Results Overview

The ACR 50 definition of improvement is a 50% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 50% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

• Recruitment status: ACTIVE_NOT_RECRUITING
• Study phase: PHASE3
• Target enrollment: 338 participants
• Primary outcome timeframe: Baseline, week 24
• Results posted on: 2025-02-19

Participant Flow

338 participants were treated during the single-blind treatment. 321 of the participants who completed the single-blind treatment continued to be treated in the open-label.

Participant milestones

Measure	Abatacept Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Overall Study STARTED	169	169
Overall Study Treated in Open-Label	160	161
Overall Study COMPLETED	162	162
Overall Study NOT COMPLETED	7	7

Reasons for withdrawal

Measure	Abatacept Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Overall Study Lack of Efficacy	2	1
Overall Study Adverse Event	1	2
Overall Study Participant request to discontinue study treatment	1	2
Overall Study Withdrawal by Subject	2	1
Overall Study other reasons	1	1

Baseline Characteristics

A Study to Compare the Response to Treatment With Abatacept vs Adalimumab, on Background Methotrexate, in Adults With Early, Seropositive, and Shared Epitope-positive Rheumatoid Arthritis and an Inadequate Response to Methotrexate

Baseline characteristics by cohort

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)	Total n=338 Participants Total of all reporting groups
Age, Continuous	49.3 Years STANDARD_DEVIATION 13.71 • n=5 Participants	47.4 Years STANDARD_DEVIATION 13.43 • n=7 Participants	48.4 Years STANDARD_DEVIATION 13.59 • n=5 Participants
Sex: Female, Male Female	130 Participants n=5 Participants	138 Participants n=7 Participants	268 Participants n=5 Participants
Sex: Female, Male Male	39 Participants n=5 Participants	31 Participants n=7 Participants	70 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	9 Participants n=5 Participants	9 Participants n=7 Participants	18 Participants n=5 Participants
Race (NIH/OMB) Asian	17 Participants n=5 Participants	23 Participants n=7 Participants	40 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	4 Participants n=5 Participants	1 Participants n=7 Participants	5 Participants n=5 Participants
Race (NIH/OMB) White	122 Participants n=5 Participants	113 Participants n=7 Participants	235 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	17 Participants n=5 Participants	23 Participants n=7 Participants	40 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline, week 24

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at week 24 or discontinuation due to any reason before week 24 are considered non-responders

The ACR 50 definition of improvement is a 50% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 50% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response at Week 24	59.0 Percentage of participants Interval 49.5 to 68.0	60.3 Percentage of participants Interval 50.8 to 69.3

SECONDARY outcome

Timeframe: Week 24

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at week 24 or discontinuation due to any reason before week 24 are considered non-responders

DAS28-CRP is a continuous variable which is a composite of 4 variables: the number of tender joints out of a pre-specified 28 joints, the number of swollen joints out of a pre-specified 28 joints, C-reactive protein in mg/L (CRP) and participant assessment of disease activity measure on a visual analogue scale (VAS) of 100mm. DAS28-CRP scores range from 0 to 10; higher scores indicate more active disease. DAS28-CRP is calculated using the following formula: DAS28-CRP(4) = 0.56*sqrt(TJC28) + 0.28*sqrt(SJC28) + 0.36*ln(CRP+1) + 0.014*GH + 0.96 where t28 = number of painful joints from 28 joints, sw28 = number of swollen joints from 28 joints, CRP = c-reactive protein in mg/L, and GH = general health or patient's global assessment of disease activity on a 100 mm VAS.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) at Week 24	44.4 Percentage of participants Interval 35.3 to 53.9	46.6 Percentage of participants Interval 37.2 to 56.0

SECONDARY outcome

Timeframe: Baseline, week 24

Population: All treated participants

The ACR 50 definition of improvement is a 50% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 50% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response at Week 24	59.2 Percentage of participants Interval 51.4 to 66.7	63.9 Percentage of participants Interval 56.2 to 71.1

SECONDARY outcome

Timeframe: Week 24

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at week 24 or discontinuation due to any reason before week 24 are considered non-responders

CDAI is a simple linear sum of the following four components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm). CDAI scores range from 2-76; higher scores indicate more active disease. CDAI is calculated using the following formula: TJC + SJC + PGA + MDGA where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, and MDGA = physician global assessment on a visual analog scale 0-10 cm.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) at Week 24	33.3 Percentage of participants Interval 24.9 to 42.6	35.3 Percentage of participants Interval 26.7 to 44.8

SECONDARY outcome

Timeframe: Baseline, week 24

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements

Participant-reported pain by a 0-100mm visual analog scale; higher score indicates more pain. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=110 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=107 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in SE+ Participant-Reported Pain Visual Analog Scale (VAS) at Week 24	-40.9 Score on a scale Standard Error 2.256	-37.7 Score on a scale Standard Error 2.288

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

The ACR 20 definition of improvement is a 20% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 20% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 29	47.0 Percentage of participants Interval 37.7 to 56.5	51.7 Percentage of participants Interval 42.3 to 61.1
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 57	66.7 Percentage of participants Interval 57.4 to 75.1	71.6 Percentage of participants Interval 62.4 to 79.5
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 85	74.4 Percentage of participants Interval 65.5 to 82.0	75.9 Percentage of participants Interval 67.0 to 83.3
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 113	85.5 Percentage of participants Interval 77.8 to 91.3	76.7 Percentage of participants Interval 68.0 to 84.1
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 141	82.9 Percentage of participants Interval 74.8 to 89.2	79.3 Percentage of participants Interval 70.8 to 86.3
Percentage of SE+ Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 169	76.9 Percentage of participants Interval 68.2 to 84.2	75.9 Percentage of participants Interval 67.0 to 83.3

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

The ACR 50 definition of improvement is a 50% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 50% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 29	20.5 Percentage of participants Interval 13.6 to 29.0	26.7 Percentage of participants Interval 18.9 to 35.7
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 85	54.7 Percentage of participants Interval 45.2 to 63.9	54.3 Percentage of participants Interval 44.8 to 63.6
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 141	60.7 Percentage of participants Interval 51.2 to 69.6	60.3 Percentage of participants Interval 50.8 to 69.3
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 169	59.0 Percentage of participants Interval 49.5 to 68.0	60.3 Percentage of participants Interval 50.8 to 69.3
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 57	38.5 Percentage of participants Interval 29.6 to 47.9	43.1 Percentage of participants Interval 33.9 to 52.6
Percentage of SE+ Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 113	60.7 Percentage of participants Interval 51.2 to 69.6	59.5 Percentage of participants Interval 50.0 to 68.5

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

The ACR 70 definition of improvement is a 70% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 70% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 29	6.8 Percentage of participants Interval 3.0 to 13.0	10.3 Percentage of participants Interval 5.5 to 17.4
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 57	17.9 Percentage of participants Interval 11.5 to 26.1	24.1 Percentage of participants Interval 16.7 to 33.0
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 85	30.8 Percentage of participants Interval 22.6 to 40.0	35.3 Percentage of participants Interval 26.7 to 44.8
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 113	35.0 Percentage of participants Interval 26.5 to 44.4	35.3 Percentage of participants Interval 26.7 to 44.8
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 141	40.2 Percentage of participants Interval 31.2 to 49.6	44.0 Percentage of participants Interval 34.8 to 53.5
Percentage of SE+ Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 169	39.3 Percentage of participants Interval 30.4 to 48.8	47.4 Percentage of participants Interval 38.1 to 56.9

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

DAS28-CRP is a continuous variable which is a composite of 4 variables: the number of tender joints out of a pre-specified 28 joints, the number of swollen joints out of a pre-specified 28 joints, C-reactive protein in mg/L (CRP) and participant assessment of disease activity measure on a visual analogue scale (VAS) of 100mm. DAS28-CRP scores range from 0 to 10; higher scores indicate more active disease. DAS28-CRP is calculated using the following formula: DAS28-CRP(4) = 0.56*sqrt(TJC28) + 0.28*sqrt(SJC28) + 0.36*ln(CRP+1) + 0.014*GH + 0.96 where t28 = number of painful joints from 28 joints, sw28 = number of swollen joints from 28 joints, CRP = c-reactive protein in mg/L, and GH = general health or patient's global assessment of disease activity on a 100 mm VAS.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 29	12.8 Percentage of participants Interval 7.4 to 20.3	16.4 Percentage of participants Interval 10.2 to 24.4
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 57	30.8 Percentage of participants Interval 22.6 to 40.0	32.8 Percentage of participants Interval 24.3 to 42.1
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 85	41.0 Percentage of participants Interval 32.0 to 50.5	40.5 Percentage of participants Interval 31.5 to 50.0
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 113	49.6 Percentage of participants Interval 40.2 to 59.0	52.6 Percentage of participants Interval 43.1 to 61.9
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 141	54.7 Percentage of participants Interval 45.2 to 63.9	52.6 Percentage of participants Interval 43.1 to 61.9
Percentage of SE+ Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 169	44.4 Percentage of participants Interval 35.3 to 53.9	46.6 Percentage of participants Interval 37.2 to 56.0

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

CDAI is a simple linear sum of the following four components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm). CDAI scores range from 2-76; higher scores indicate more active disease. CDAI is calculated using the following formula: TJC + SJC + PGA + MDGA where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, and MDGA = physician global assessment on a visual analog scale 0-10 cm.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 85	26.5 Percentage of participants Interval 18.8 to 35.5	19.8 Percentage of participants Interval 13.0 to 28.3
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 113	29.1 Percentage of participants Interval 21.0 to 38.2	32.8 Percentage of participants Interval 24.3 to 42.1
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 29	9.4 Percentage of participants Interval 4.8 to 16.2	6.0 Percentage of participants Interval 2.5 to 12.0
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 57	17.1 Percentage of participants Interval 10.8 to 25.2	13.8 Percentage of participants Interval 8.1 to 21.4
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 141	34.2 Percentage of participants Interval 25.7 to 43.5	30.2 Percentage of participants Interval 22.0 to 39.4
Percentage of SE+ Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 169	33.3 Percentage of participants Interval 24.9 to 42.6	35.3 Percentage of participants Interval 26.7 to 44.8

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline. SE+ participants with missing data at each timepoint are considered non-responders

SDAI is a simple linear sum of the following five components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm), high-sensitivity C-reactive protein (hsCRP mg/dL). SDAI total scores range from 0-86; higher scores indicate more active disease. SDAI is calculated using the following formula: TJC + SJC + PGA + MDGA + CRP where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, MDGA = physician global assessment on a visual analog scale 0-10 cm, and CRP = c-reactive protein in mg/dL.

Outcome measures

Measure	Abatacept n=117 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=116 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 85	24.8 Percentage of participants Interval 17.3 to 33.6	19.8 Percentage of participants Interval 13.0 to 28.3
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 113	31.6 Percentage of participants Interval 23.3 to 40.9	31.9 Percentage of participants Interval 23.6 to 41.2
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 169	33.3 Percentage of participants Interval 24.9 to 42.6	34.5 Percentage of participants Interval 25.9 to 43.9
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 29	9.4 Percentage of participants Interval 4.8 to 16.2	7.8 Percentage of participants Interval 3.6 to 14.2
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 57	17.1 Percentage of participants Interval 10.8 to 25.2	14.7 Percentage of participants Interval 8.8 to 22.4
Percentage of SE+ Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 141	35.9 Percentage of participants Interval 27.2 to 45.3	32.8 Percentage of participants Interval 24.3 to 42.1

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

The ACR 20 definition of improvement is a 20% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 20% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 29	46.7 Percentage of participants Interval 39.0 to 54.6	52.1 Percentage of participants Interval 44.3 to 59.8
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 57	66.3 Percentage of participants Interval 58.6 to 73.4	68.6 Percentage of participants Interval 61.1 to 75.5
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 85	72.8 Percentage of participants Interval 65.4 to 79.3	76.3 Percentage of participants Interval 69.2 to 82.5
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 113	85.2 Percentage of participants Interval 78.9 to 90.2	79.9 Percentage of participants Interval 73.0 to 85.6
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 141	84.0 Percentage of participants Interval 77.6 to 89.2	79.9 Percentage of participants Interval 73.0 to 85.6
Percentage of Participants Meeting 20% Improvement in American College of Rheumatology Criteria (ACR20) Response Over Time Day 169	77.5 Percentage of participants Interval 70.5 to 83.6	76.9 Percentage of participants Interval 69.8 to 83.0

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

The ACR 50 definition of improvement is a 50% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 50% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 29	20.1 Percentage of participants Interval 14.4 to 27.0	27.2 Percentage of participants Interval 20.7 to 34.6
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 169	59.2 Percentage of participants Interval 51.4 to 66.7	63.9 Percentage of participants Interval 56.2 to 71.1
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 57	38.5 Percentage of participants Interval 31.1 to 46.2	41.4 Percentage of participants Interval 33.9 to 49.2
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 85	52.7 Percentage of participants Interval 44.9 to 60.4	53.3 Percentage of participants Interval 45.4 to 61.0
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 113	60.4 Percentage of participants Interval 52.6 to 67.8	59.8 Percentage of participants Interval 52.0 to 67.2
Percentage of Participants Meeting 50% Improvement in American College of Rheumatology Criteria (ACR50) Response Over Time Day 141	61.5 Percentage of participants Interval 53.8 to 68.9	58.6 Percentage of participants Interval 50.8 to 66.1

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

The ACR 70 definition of improvement is a 70% improvement over baseline in tender and swollen joint counts (#1 and #2) and a 70% improvement in 3 of the 5 remaining core data set measures (Participant global assessment of pain, participant global assessment of disease activity, physician global assessment of disease activity, participant assessment of physical function, and acute phase reactant value). Baseline value is the last assessment taken prior to first dose of single-blind study medication.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 85	30.2 Percentage of participants Interval 23.4 to 37.7	32.0 Percentage of participants Interval 25.0 to 39.6
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 113	35.5 Percentage of participants Interval 28.3 to 43.2	33.7 Percentage of participants Interval 26.6 to 41.4
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 141	40.2 Percentage of participants Interval 32.8 to 48.0	40.8 Percentage of participants Interval 33.3 to 48.6
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 29	5.9 Percentage of participants Interval 2.9 to 10.6	10.1 Percentage of participants Interval 6.0 to 15.6
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 57	20.7 Percentage of participants Interval 14.9 to 27.6	23.1 Percentage of participants Interval 17.0 to 30.2
Percentage of Participants Meeting 70% Improvement in American College of Rheumatology Criteria (ACR70) Response Over Time Day 169	39.1 Percentage of participants Interval 31.7 to 46.8	45.0 Percentage of participants Interval 37.3 to 52.8

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

DAS28-CRP is a continuous variable which is a composite of 4 variables: the number of tender joints out of a pre-specified 28 joints, the number of swollen joints out of a pre-specified 28 joints, C-reactive protein in mg/L (CRP) and participant assessment of disease activity measure on a visual analogue scale (VAS) of 100mm. DAS28-CRP scores range from 0 to 10; higher scores indicate more active disease. DAS28-CRP is calculated using the following formula: DAS28-CRP(4) = 0.56*sqrt(TJC28) + 0.28*sqrt(SJC28) + 0.36*ln(CRP+1) + 0.014*GH + 0.96 where t28 = number of painful joints from 28 joints, sw28 = number of swollen joints from 28 joints, CRP = c-reactive protein in mg/L, and GH = general health or patient's global assessment of disease activity on a 100 mm VAS.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 29	10.7 Percentage of participants Interval 6.4 to 16.3	16.6 Percentage of participants Interval 11.3 to 23.0
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 57	27.2 Percentage of participants Interval 20.7 to 34.6	33.7 Percentage of participants Interval 26.6 to 41.4
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 85	37.3 Percentage of participants Interval 30.0 to 45.0	40.8 Percentage of participants Interval 33.3 to 48.6
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 113	49.7 Percentage of participants Interval 41.9 to 57.5	54.4 Percentage of participants Interval 46.6 to 62.1
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 141	54.4 Percentage of participants Interval 46.6 to 62.1	51.5 Percentage of participants Interval 43.7 to 59.2
Percentage of Participants Achieving Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein Remission (DAS28-CRP < 2.6) Over Time Day 169	46.7 Percentage of participants Interval 39.0 to 54.6	50.9 Percentage of participants Interval 43.1 to 58.6

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

CDAI is a simple linear sum of the following four components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm). CDAI scores range from 2-76; higher scores indicate more active disease. CDAI is calculated using the following formula: TJC + SJC + PGA + MDGA where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, and MDGA = physician global assessment on a visual analog scale 0-10 cm.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 29	7.7 Percentage of participants Interval 4.2 to 12.8	6.5 Percentage of participants Interval 3.3 to 11.3
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 57	15.4 Percentage of participants Interval 10.3 to 21.7	14.2 Percentage of participants Interval 9.3 to 20.4
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 85	24.9 Percentage of participants Interval 18.5 to 32.1	20.7 Percentage of participants Interval 14.9 to 27.6
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 113	31.4 Percentage of participants Interval 24.5 to 38.9	29.0 Percentage of participants Interval 22.3 to 36.5
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 141	34.3 Percentage of participants Interval 27.2 to 42.0	29.0 Percentage of participants Interval 22.3 to 36.5
Percentage of Participants Achieving Clinical Disease Activity Index Remission (CDAI <= 2.8) Over Time Day 169	33.7 Percentage of participants Interval 26.6 to 41.4	32.5 Percentage of participants Interval 25.5 to 40.2

SECONDARY outcome

Timeframe: Day 29, 57, 85, 113, 141, 169

Population: All treated participants. Participants with missing data at each timepoint are considered non-responders

SDAI is a simple linear sum of the following five components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm), high-sensitivity C-reactive protein (hsCRP mg/dL). SDAI total scores range from 0-86; higher scores indicate more active disease. SDAI is calculated using the following formula: TJC + SJC + PGA + MDGA + CRP where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, MDGA = physician global assessment on a visual analog scale 0-10 cm, and CRP = c-reactive protein in mg/dL.

Outcome measures

Measure	Abatacept n=169 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 29	7.7 Percentage of participants Interval 4.2 to 12.8	7.7 Percentage of participants Interval 4.2 to 12.8
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 169	34.3 Percentage of participants Interval 27.2 to 42.0	31.4 Percentage of participants Interval 24.5 to 38.9
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 57	14.8 Percentage of participants Interval 9.8 to 21.1	16.0 Percentage of participants Interval 10.8 to 22.4
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 85	23.1 Percentage of participants Interval 17.0 to 30.2	20.7 Percentage of participants Interval 14.9 to 27.6
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 113	33.1 Percentage of participants Interval 26.1 to 40.8	28.4 Percentage of participants Interval 21.7 to 35.8
Percentage of Participants Achieving Simple Disease Activity Index Remission (SDAI <= 3.3) Over Time Day 141	35.5 Percentage of participants Interval 28.3 to 43.2	28.4 Percentage of participants Interval 21.7 to 35.8

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

DAS28-CRP is a continuous variable which is a composite of 4 variables: the number of tender joints out of a pre-specified 28 joints, the number of swollen joints out of a pre-specified 28 joints, C-reactive protein in mg/L (CRP) and participant assessment of disease activity measure on a visual analogue scale (VAS) of 100mm. DAS28-CRP scores range from 0 to 10; higher scores indicate more active disease. Remission was defined as DAS28-CRP < 2.6. DAS28-CRP is calculated using the following formula: DAS28-CRP(4) = 0.56*sqrt(TJC28) + 0.28*sqrt(SJC28) + 0.36*ln(CRP+1) + 0.014*GH + 0.96 where t28 = number of painful joints from 28 joints, sw28 = number of swollen joints from 28 joints, CRP = c-reactive protein in mg/L, and GH = general health or patient's global assessment of disease activity on a 100 mm VAS. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=115 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=113 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 29	-1.3 score on a scale Standard Error 0.099	-1.6 score on a scale Standard Error 0.099
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 57	-2.0 score on a scale Standard Error 0.104	-2.1 score on a scale Standard Error 0.109
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 85	-2.3 score on a scale Standard Error 0.109	-2.4 score on a scale Standard Error 0.112
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 169	-2.6 score on a scale Standard Error 0.114	-2.6 score on a scale Standard Error 0.116
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 113	-2.7 score on a scale Standard Error 0.099	-2.6 score on a scale Standard Error 0.101
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for SE+ Participants Day 141	-2.7 score on a scale Standard Error 0.101	-2.6 score on a scale Standard Error 0.102

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

CDAI is a simple linear sum of the following four components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm). CDAI scores range from 2-76; higher scores indicate more active disease. CDAI remission was defined as =<2.8. CDAI is calculated using the following formula: TJC + SJC + PGA + MDGA where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, and MDGA = physician global assessment on a visual analog scale 0-10 cm. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=113 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=114 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 29	-15.5 score on a scale Standard Error 0.972	-15.9 score on a scale Standard Error 0.955
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 113	-26.8 score on a scale Standard Error 0.798	-25.6 score on a scale Standard Error 0.808
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 141	-27.3 score on a scale Standard Error 0.783	-25.6 score on a scale Standard Error 0.780
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 169	-26.9 score on a scale Standard Error 0.959	-25.5 score on a scale Standard Error 0.959
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 57	-21.3 score on a scale Standard Error 0.928	-21.9 score on a scale Standard Error 0.949
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for SE+ Participants Day 85	-24.6 score on a scale Standard Error 0.928	-23.7 score on a scale Standard Error 0.945

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

SDAI is a simple linear sum of the following five components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm), high-sensitivity C-reactive protein (hsCRP mg/dL). SDAI total scores range from 0-86; higher scores indicate more active disease. Remission was defined as SDAI =< 3.3. SDAI is calculated using the following formula: TJC + SJC + PGA + MDGA + CRP where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, MDGA = physician global assessment on a visual analog scale 0-10 cm, and CRP = c-reactive protein in mg/dL. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=113 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=113 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 29	-15.6 score on a scale Standard Error 1.008	-16.7 score on a scale Standard Error 0.990
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 57	-21.9 score on a scale Standard Error 0.931	-22.5 score on a scale Standard Error 0.962
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 85	-25.3 score on a scale Standard Error 0.935	-24.6 score on a scale Standard Error 0.953
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 169	-27.6 score on a scale Standard Error 0.978	-26.1 score on a scale Standard Error 0.983
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 113	-27.5 score on a scale Standard Error 0.797	-26.3 score on a scale Standard Error 0.807
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for SE+ Participants Day 141	-28.1 score on a scale Standard Error 0.791	-26.4 score on a scale Standard Error 0.787

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=115 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=114 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 29: Participants Global Assess Disease Activity (mm)	-20.0 score on a scale Standard Error 2.230	-21.4 score on a scale Standard Error 2.230
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 29: Physician Global Assess Disease Activity (mm)	-26.8 score on a scale Standard Error 1.896	-27.1 score on a scale Standard Error 1.870
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 29: Participants Assessment of Pain (mm)	-19.5 score on a scale Standard Error 2.219	-23.6 score on a scale Standard Error 2.229
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 57: Participants Assessment of Pain (mm)	-24.8 score on a scale Standard Error 2.305	-29.1 score on a scale Standard Error 2.358
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 85: Participants Global Assess Disease Activity (mm)	-33.4 score on a scale Standard Error 2.239	-32.9 score on a scale Standard Error 2.302
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 85: Physician Global Assess Disease Activity (mm)	-43.8 score on a scale Standard Error 1.660	-42.2 score on a scale Standard Error 1.675
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 85: Participants Assessment of Pain (mm)	-33.1 score on a scale Standard Error 2.321	-33.3 score on a scale Standard Error 2.363
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 113: Participants Global Assess Disease Activity (mm)	-37.7 score on a scale Standard Error 2.124	-35.7 score on a scale Standard Error 2.162
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 113: Physician Global Assess Disease Activity (mm)	-47.6 score on a scale Standard Error 1.462	-45.8 score on a scale Standard Error 1.482
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 141: Participants Global Assess Disease Activity (mm)	-38.8 score on a scale Standard Error 2.243	-35.0 score on a scale Standard Error 2.274
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 141: Physician Global Assess Disease Activity (mm)	-48.9 score on a scale Standard Error 1.498	-45.7 score on a scale Standard Error 1.491
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 169: Participants Global Assess Disease Activity (mm)	-39.6 score on a scale Standard Error 2.237	-36.0 score on a scale Standard Error 2.278
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 169: Physician Global Assess Disease Activity (mm)	-48.0 score on a scale Standard Error 1.683	-45.9 score on a scale Standard Error 1.683
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 169: Participants Assessment of Pain (mm)	-40.9 score on a scale Standard Error 2.256	-37.7 score on a scale Standard Error 2.288
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 57: Participants Global Assess Disease Activity (mm)	-25.7 score on a scale Standard Error 2.205	-28.4 score on a scale Standard Error 2.276
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 57: Physician Global Assess Disease Activity (mm)	-37.7 score on a scale Standard Error 1.782	-37.6 score on a scale Standard Error 1.806
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 113: Participants Assessment of Pain (mm)	-37.0 score on a scale Standard Error 2.207	-34.3 score on a scale Standard Error 2.237
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for SE+ Participants Day 141: Participants Assessment of Pain (mm)	-39.0 score on a scale Standard Error 2.212	-38.3 score on a scale Standard Error 2.223

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=115 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=114 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 29: Total Tender Joint Count	-9.1 Joints count Standard Error 0.580	-8.6 Joints count Standard Error 0.580
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 29: Total Swollen Joint Count	-6.2 Joints count Standard Error 0.422	-6.7 Joints count Standard Error 0.422
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 57: Total Tender Joint Count	-11.9 Joints count Standard Error 0.608	-11.6 Joints count Standard Error 0.621
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 57: Total Swollen Joint Count	-8.6 Joints count Standard Error 0.378	-8.8 Joints count Standard Error 0.386
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 85: Total Tender Joint Count	-13.5 Joints count Standard Error 0.608	-12.7 Joints count Standard Error 0.618
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 85: Total Swollen Joint Count	-9.5 Joints count Standard Error 0.352	-9.4 Joints count Standard Error 0.358
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 113: Total Tender Joint Count	-14.5 Joints count Standard Error 0.516	-13.8 Joints count Standard Error 0.526
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 113: Total Swollen Joint Count	-10.1 Joints count Standard Error 0.321	-9.8 Joints count Standard Error 0.326
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 141: Total Tender Joint Count	-14.8 Joints count Standard Error 0.499	-13.9 Joints count Standard Error 0.506
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 141: Total Swollen Joint Count	-10.4 Joints count Standard Error 0.321	-9.8 Joints count Standard Error 0.325
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 169: Total Tender Joint Count	-14.7 Joints count Standard Error 0.580	-13.8 Joints count Standard Error 0.583
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for SE+ Participants Day 169: Total Swollen Joint Count	-10.2 Joints count Standard Error 0.397	-9.7 Joints count Standard Error 0.399

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

6) Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI). For the eight disability categories (Dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities), there is an aids or devices variables to record the type of assistance. If aids or devices and/or assistance from another person are checked for a category, the score is set to 2 (much difficulty), if the original score is 0 (no difficulty) or 1 (some difficulty). HAQ-DI is then calculated by summing the adjusted categories scores and dividing by the number of categories answered (increasing scores for the 8 disability categories questionnaire indicate increasing level of difficulty with 0 being the lowest score "without any difficulty" and 3 being the highest score "unable to do".

Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=115 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=114 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 29: Disability Index	-0.4 score on a scale Standard Error 0.047	-0.5 score on a scale Standard Error 0.047
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 57: Disability Index	-0.6 score on a scale Standard Error 0.049	-0.6 score on a scale Standard Error 0.050
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 85: Disability Index	-0.8 score on a scale Standard Error 0.050	-0.7 score on a scale Standard Error 0.051
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 113: Disability Index	-0.8 score on a scale Standard Error 0.047	-0.7 score on a scale Standard Error 0.048
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 141: Disability Index	-0.9 score on a scale Standard Error 0.046	-0.8 score on a scale Standard Error 0.046
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for SE+ Participants Day 169: Disability Index	-0.9 score on a scale Standard Error 0.049	-0.8 score on a scale Standard Error 0.050

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=115 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=114 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 29: C Reactive Protein (mg/L)	-1.4 mg/L Standard Error 1.986	-8.1 mg/L Standard Error 1.995
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 57: C Reactive Protein (mg/L)	-6.1 mg/L Standard Error 0.818	-7.4 mg/L Standard Error 0.845
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 85: C Reactive Protein (mg/L)	-6.7 mg/L Standard Error 0.745	-8.6 mg/L Standard Error 0.759
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 113: C Reactive Protein (mg/L)	-7.5 mg/L Standard Error 0.701	-7.3 mg/L Standard Error 0.713
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 141: C Reactive Protein (mg/L)	-7.9 mg/L Standard Error 0.724	-7.6 mg/L Standard Error 0.733
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for SE+ Participants Day 169: C Reactive Protein (mg/L)	-6.6 mg/L Standard Error 1.083	-5.4 mg/L Standard Error 1.098

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

DAS28-CRP is a continuous variable which is a composite of 4 variables: the number of tender joints out of a pre-specified 28 joints, the number of swollen joints out of a pre-specified 28 joints, C-reactive protein in mg/L (CRP) and participant assessment of disease activity measure on a visual analogue scale (VAS) of 100mm. DAS28-CRP scores range from 0 to 10; higher scores indicate more active disease. Remission was defined as DAS28-CRP < 2.6. DAS28-CRP is calculated using the following formula: DAS28-CRP(4) = 0.56*sqrt(TJC28) + 0.28*sqrt(SJC28) + 0.36*ln(CRP+1) + 0.014*GH + 0.96 where t28 = number of painful joints from 28 joints, sw28 = number of swollen joints from 28 joints, CRP = c-reactive protein in mg/L, and GH = general health or patient's global assessment of disease activity on a 100 mm VAS. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=165 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=164 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 29	-1.2 score on a scale Standard Error 0.084	-1.5 score on a scale Standard Error 0.084
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 57	-1.9 score on a scale Standard Error 0.089	-2.1 score on a scale Standard Error 0.089
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 85	-2.2 score on a scale Standard Error 0.091	-2.4 score on a scale Standard Error 0.091
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 113	-2.6 score on a scale Standard Error 0.084	-2.6 score on a scale Standard Error 0.084
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 141	-2.7 score on a scale Standard Error 0.085	-2.5 score on a scale Standard Error 0.085
Adjusted Mean Change From Baseline in Disease Activity Score 28 Joint Count Calculated Using C Reactive Protein (DAS28-CRP) Over Time for All Participants Day 169	-2.6 score on a scale Standard Error 0.094	-2.6 score on a scale Standard Error 0.093

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

CDAI is a simple linear sum of the following four components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm). CDAI scores range from 2-76; higher scores indicate more active disease. CDAI remission was defined as =<2.8. CDAI is calculated using the following formula: TJC + SJC + PGA + MDGA where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, and MDGA = physician global assessment on a visual analog scale 0-10 cm. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=163 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=163 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 29	-14.6 score on a scale Standard Error 0.818	-15.9 score on a scale Standard Error 0.823
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 57	-20.9 score on a scale Standard Error 0.786	-21.6 score on a scale Standard Error 0.784
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 85	-23.5 score on a scale Standard Error 0.763	-23.5 score on a scale Standard Error 0.769
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 113	-26.6 score on a scale Standard Error 0.644	-25.4 score on a scale Standard Error 0.646
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 141	-27.1 score on a scale Standard Error 0.647	-25.2 score on a scale Standard Error 0.631
Adjusted Mean Change From Baseline in Clinical Disease Activity Index (CDAI) Over Time for All Participants Day 169	-26.7 score on a scale Standard Error 0.763	-25.4 score on a scale Standard Error 0.749

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

SDAI is a simple linear sum of the following five components: Tender joint counts out of 28 joints, Swollen joint counts out of 28 joints, Participant global assessment of disease activity (0-10cm), Physicians global assessment of disease activity (0-10cm), high-sensitivity C-reactive protein (hsCRP mg/dL). SDAI total scores range from 0-86; higher scores indicate more active disease. Remission was defined as SDAI =< 3.3. SDAI is calculated using the following formula: TJC + SJC + PGA + MDGA + CRP where TJC = number of painful joints from 28 joints, SJC = number of swollen joints from 28 joints, PGA = patient global assessment on a visual analog scale 0-10 cm, MDGA = physician global assessment on a visual analog scale 0-10 cm, and CRP = c-reactive protein in mg/dL. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=163 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=162 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 29	-14.7 Score on a scale Standard Error 0.843	-16.6 Score on a scale Standard Error 0.849
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 57	-21.5 Score on a scale Standard Error 0.788	-22.1 Score on a scale Standard Error 0.789
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 85	-24.0 Score on a scale Standard Error 0.769	-24.2 Score on a scale Standard Error 0.775
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 113	-27.2 Score on a scale Standard Error 0.648	-26.0 Score on a scale Standard Error 0.649
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 141	-27.7 Score on a scale Standard Error 0.661	-25.8 Score on a scale Standard Error 0.647
Adjusted Mean Change From Baseline in Simple Disease Activity Index (SDAI) Over Time for All Participants Day 169	-27.3 Score on a scale Standard Error 0.787	-26.0 Score on a scale Standard Error 0.771

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=166 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=166 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 29: Participants Global Assess Disease Activity (mm)	-19.4 score on a scale Standard Error 1.865	-20.6 score on a scale Standard Error 1.868
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 29: Physician Global Assess Disease Activity (mm)	-24.4 score on a scale Standard Error 1.613	-27.7 score on a scale Standard Error 1.612
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 29: Participants Assessment of Pain (mm)	-19.2 score on a scale Standard Error 1.872	-22.7 score on a scale Standard Error 1.863
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 57: Participants Global Assess Disease Activity (mm)	-27.3 score on a scale Standard Error 1.888	-28.3 score on a scale Standard Error 1.893
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 57: Physician Global Assess Disease Activity (mm)	-35.7 score on a scale Standard Error 1.583	-36.7 score on a scale Standard Error 1.579
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 57: Participants Assessment of Pain (mm)	-25.9 score on a scale Standard Error 1.957	-28.7 score on a scale Standard Error 1.954
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 85: Physician Global Assess Disease Activity (mm)	-40.1 score on a scale Standard Error 1.459	-41.2 score on a scale Standard Error 1.459
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 85: Participants Assessment of Pain (mm)	-32.1 score on a scale Standard Error 1.939	-33.7 score on a scale Standard Error 1.923
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 113: Participants Global Assess Disease Activity (mm)	-37.7 score on a scale Standard Error 1.787	-34.8 score on a scale Standard Error 1.780
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 113: Physician Global Assess Disease Activity (mm)	-46.8 score on a scale Standard Error 1.216	-44.9 score on a scale Standard Error 1.218
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 113: Participants Assessment of Pain (mm)	-36.6 score on a scale Standard Error 1.883	-33.9 score on a scale Standard Error 1.871
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 141: Participants Global Assess Disease Activity (mm)	-38.4 score on a scale Standard Error 1.866	-34.1 score on a scale Standard Error 1.856
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 141: Physician Global Assess Disease Activity (mm)	-48.5 score on a scale Standard Error 1.258	-45.2 score on a scale Standard Error 1.221
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 141: Participants Assessment of Pain (mm)	-38.7 score on a scale Standard Error 1.858	-35.4 score on a scale Standard Error 1.830
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 169: Participants Global Assess Disease Activity (mm)	-39.1 score on a scale Standard Error 1.842	-36.6 score on a scale Standard Error 1.827
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 169: Physician Global Assess Disease Activity (mm)	-47.7 score on a scale Standard Error 1.320	-46.2 score on a scale Standard Error 1.296
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 169: Participants Assessment of Pain (mm)	-39.5 score on a scale Standard Error 1.895	-37.0 score on a scale Standard Error 1.864
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 3-5 Over Time for All Participants Day 85: Participants Global Assess Disease Activity (mm)	-32.8 score on a scale Standard Error 1.874	-32.8 score on a scale Standard Error 1.884

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=166 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=167 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 29: Total Tender Joint Count	-8.1 Joints count Standard Error 0.529	-8.2 Joints count Standard Error 0.527
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 29: Total Swollen Joint Count	-6.1 Joints count Standard Error 0.374	-6.6 Joints count Standard Error 0.372
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 57: Total Tender Joint Count	-11.3 Joints count Standard Error 0.549	-11.1 Joints count Standard Error 0.545
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 57: Total Swollen Joint Count	-8.7 Joints count Standard Error 0.322	-8.7 Joints count Standard Error 0.319
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 85: Total Tender Joint Count	-12.7 Joints count Standard Error 0.507	-12.4 Joints count Standard Error 0.506
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 85: Total Swollen Joint Count	-9.3 Joints count Standard Error 0.289	-9.4 Joints count Standard Error 0.289
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 113: Total Tender Joint Count	-14.4 Joints count Standard Error 0.411	-13.9 Joints count Standard Error 0.410
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 113: Total Swollen Joint Count	-10.1 Joints count Standard Error 0.255	-9.8 Joints count Standard Error 0.254
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 141: Total Swollen Joint Count	-10.6 Joints count Standard Error 0.259	-9.9 Joints count Standard Error 0.257
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 169: Total Tender Joint Count	-14.5 Joints count Standard Error 0.474	-13.8 Joints count Standard Error 0.468
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 169: Total Swollen Joint Count	-10.2 Joints count Standard Error 0.311	-9.8 Joints count Standard Error 0.307
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 1-2 Over Time for All Participants Day 141: Total Tender Joint Count	-14.8 Joints count Standard Error 0.417	-13.8 Joints count Standard Error 0.414

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

6) Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI). For the eight disability categories (Dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities), there is an aids or devices variables to record the type of assistance. If aids or devices and/or assistance from another person are checked for a category, the score is set to 2 (much difficulty), if the original score is 0 (no difficulty) or 1 (some difficulty). HAQ-DI is then calculated by summing the adjusted categories scores and dividing by the number of categories answered (increasing scores for the 8 disability categories questionnaire indicate increasing level of difficulty with 0 being the lowest score "without any difficulty" and 3 being the highest score "unable to do".

Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=166 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=165 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 29: Disability Index	-0.4 score on a scale Standard Error 0.040	-0.5 score on a scale Standard Error 0.040
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 57: Disability Index	-0.6 score on a scale Standard Error 0.042	-0.6 score on a scale Standard Error 0.042
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 85: Disability Index	-0.7 score on a scale Standard Error 0.043	-0.6 score on a scale Standard Error 0.043
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 113: Disability Index	-0.7 score on a scale Standard Error 0.041	-0.7 score on a scale Standard Error 0.041
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 141: Disability Index	-0.8 score on a scale Standard Error 0.040	-0.7 score on a scale Standard Error 0.040
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 6 Over Time for All Participants Day 169: Disability Index	-0.8 score on a scale Standard Error 0.042	-0.8 score on a scale Standard Error 0.042

SECONDARY outcome

Timeframe: Baseline, day 29, 57, 85, 113, 141, 169

Population: All treated participants with both baseline and post-baseline measurements. Non-responders are not included

1. Tender joint count (standard 68 joint count)

2. Swollen joint count (standard 66 joint count)

3. Participant global assessment of pain (a 0-100mm visual analog scale with 100 mm being the worst pain)

4. Participant global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the highest disease activity)

5. Physician global assessment of disease activity (a 0-100mm visual analog scale with 100 mm being the worst case)

6. Participant assessment of physical function Health Assessment Questionnaire Disability Index (HAQ-DI) (increasing scores for the 8 disability categories indicate increasing level of difficulty). HAQDI is calculated by summing the adjusted categories scores and dividing by the number of categories answered

7. C-reactive protein (increasing levels indicate increasing level of disease) Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline=Post-baseline - Baseline value.

Outcome measures

Measure	Abatacept n=166 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=166 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 29: C Reactive Protein (mg/L)	-1.4 mg/L Standard Error 1.520	-6.8 mg/L Standard Error 1.514
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 57: C Reactive Protein (mg/L)	-5.7 mg/L Standard Error 0.635	-6.4 mg/L Standard Error 0.635
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 85: C Reactive Protein (mg/L)	-5.4 mg/L Standard Error 0.719	-6.6 mg/L Standard Error 0.717
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 113: C Reactive Protein (mg/L)	-5.7 mg/L Standard Error 0.704	-5.8 mg/L Standard Error 0.702
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 141: C Reactive Protein (mg/L)	-5.9 mg/L Standard Error 0.778	-5.5 mg/L Standard Error 0.774
Adjusted Mean Change From Baseline in American College of Rheumatology (ACR) Core Components 7 Over Time for All Participants Day 169: C Reactive Protein (mg/L)	-6.2 mg/L Standard Error 0.912	-5.0 mg/L Standard Error 0.900

SECONDARY outcome

Timeframe: Up to week 24

Population: All participants that are shared epitope-positive (SE+) at baseline with both baseline and post-baseline measurements

SF-36 is a generic 36-item questionnaire measuring health-related quality of life, which covers 8 health dimensions within 2 components. The physical component summary (PCS) consists of these 4 subscales: Physical functioning, Role-physical, Bodily pain, General health. The mental component summary (MCS) consists of these 4 subscales: Vitality, Social functioning, Role-emotional, Mental health. Participants self-report on items in a subscale that have between 2-6 choices per item using Likert-type responses (e.g. none of the time, some of the time). Summations of item scores of the same subscale give the subscale scores, which are transformed into a range from 0 to 100, with a higher score indicating better quality of life. The 8 subscales will be scored using norm-based methods that have standardized the T-scores to a mean of 50 and a standard deviation of 10 in the general population.

Outcome measures

Measure	Abatacept n=110 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=109 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Physical Functioning	9.2 T-score Standard Error 0.813	9.8 T-score Standard Error 0.817
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Role-Physical	9.1 T-score Standard Error 0.809	8.9 T-score Standard Error 0.805
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Bodily Pain	14.2 T-score Standard Error 0.863	12.0 T-score Standard Error 0.859
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: General Health	8.1 T-score Standard Error 0.779	6.5 T-score Standard Error 0.783
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Vitality	10.0 T-score Standard Error 0.878	8.4 T-score Standard Error 0.874
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Social Functioning	9.6 T-score Standard Error 0.828	9.4 T-score Standard Error 0.824
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Role-Emotional	9.0 T-score Standard Error 0.921	9.1 T-score Standard Error 0.917
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Mental Health	8.9 T-score Standard Error 0.799	7.1 T-score Standard Error 0.795
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Physical Component Summary	10.2 T-score Standard Error 0.738	9.6 T-score Standard Error 0.735
Adjusted Mean Change From Baseline in 36-item Short Form Survey (SF-36) Over Time for SE+ Participants Day 169: Mental Component Summary	8.4 T-score Standard Error 0.818	7.3 T-score Standard Error 0.814

SECONDARY outcome

Timeframe: Up to week 24

Population: All treated participants with both baseline and post-baseline measurements

SF-36 is a generic 36-item questionnaire measuring health-related quality of life, which covers 8 health dimensions within 2 components. The physical component summary (PCS) consists of these 4 subscales: Physical functioning, Role-physical, Bodily pain, General health. The mental component summary (MCS) consists of these 4 subscales: Vitality, Social functioning, Role-emotional, Mental health. Participants self-report on items in a subscale that have between 2-6 choices per item using Likert-type responses (e.g. none of the time, some of the time). Summations of item scores of the same subscale give the subscale scores, which are transformed into a range from 0 to 100, with a higher score indicating better quality of life. The 8 subscales will be scored using norm-based methods that have standardized the T-scores to a mean of 50 and a standard deviation of 10 in the general population.

Outcome measures

Measure	Abatacept n=159 Participants Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=161 Participants Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Physical Functioning	8.9 T-score Standard Error 0.706	9.4 T-score Standard Error 0.697
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Role-Physical	8.6 T-score Standard Error 0.681	8.7 T-score Standard Error 0.669
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: General Health	7.9 T-score Standard Error 0.652	6.7 T-score Standard Error 0.644
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Vitality	9.4 T-score Standard Error 0.740	8.8 T-score Standard Error 0.725
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Social Functioning	8.9 T-score Standard Error 0.701	9.8 T-score Standard Error 0.690
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Role-Emotional	8.4 T-score Standard Error 0.773	8.8 T-score Standard Error 0.759
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Mental Health	8.0 T-score Standard Error 0.712	7.6 T-score Standard Error 0.700
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Physical Component Summary	9.9 T-score Standard Error 0.619	9.2 T-score Standard Error 0.608
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Mental Component Summary	7.6 T-score Standard Error 0.718	7.7 T-score Standard Error 0.705
Adjusted Mean Change From Baseline in SF-36 Over Time for All Participants Day 169: Bodily Pain	13.5 T-score Standard Error 0.719	11.7 T-score Standard Error 0.706

SECONDARY outcome

Timeframe: Up to week 24

The SF-36 v2.0, which covers 8 health dimensions within 2 components. The physical component summary (PCS) of the SF-36 consists of these 4 subscales: Physical functioning, Role-physical, Bodily pain, General health. The mental component summary (MCS) of the SF-36 consists of these 4 subscales: Vitality, Social functioning, Role-emotional, Mental health. The scores range from 0 to 100, with a higher score indicating better quality of life. The 2 summary scores (PCS and MCS) will be calculated by taking a weighted linear combination of the 8 individual subscales. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to week 24

The SF-36 v2.0, which covers 8 health dimensions within 2 components. The physical component summary (PCS) of the SF-36 consists of these 4 subscales: Physical functioning, Role-physical, Bodily pain, General health. The mental component summary (MCS) of the SF-36 consists of these 4 subscales: Vitality, Social functioning, Role-emotional, Mental health. The scores range from 0 to 100, with a higher score indicating better quality of life. The 2 summary scores (PCS and MCS) will be calculated by taking a weighted linear combination of the 8 individual subscales. Baseline value is the last assessment taken prior to first dose of single-blind study medication. Change from Baseline = Post-baseline - Baseline value.

Outcome measures

Outcome data not reported

Adverse Events

Abatacept Only

Serious events: 4 serious events

Other events: 34 other events

Deaths: 0 deaths

Adalimumab, Then Abatacept (OLE Period)

Serious events: 6 serious events

Other events: 41 other events

Deaths: 0 deaths

Serious adverse events

Measure	Abatacept Only n=169 participants at risk Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 participants at risk Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Infections and infestations Atypical pneumonia	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Infections and infestations Pilonidal disease	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Injury, poisoning and procedural complications Open fracture	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Musculoskeletal and connective tissue disorders Arthritis	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Musculoskeletal and connective tissue disorders Foot deformity	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Neuroendocrine tumour	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Nervous system disorders Migraine with aura	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Renal and urinary disorders Renal colic	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Respiratory, thoracic and mediastinal disorders Chronic obstructive pulmonary disease	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Vascular disorders Haematoma	0.00% 0/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	0.59% 1/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,

Other adverse events

Measure	Abatacept Only n=169 participants at risk Participants self-administered Abatacept 125 mg subcutaneous injection weekly up to and including Week 103 (Day 722) with background stable methotrexate therapy	Adalimumab, Then Abatacept (OLE Period) n=169 participants at risk Participants self-administered Adalimumab 40 mg subcutaneous injection once every 2 weeks up to and including Week 22 (Day 155) with background stable methotrexate therapy. Those participants who entered the OL phase then took 125 mg Abatacept, which was self-administered subcutaneous weekly up to and including Week 103 (Day 722)
Infections and infestations COVID-19	11.8% 20/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	13.6% 23/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Infections and infestations Nasopharyngitis	6.5% 11/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	5.9% 10/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,
Infections and infestations Upper respiratory tract infection	2.4% 4/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,	5.9% 10/169 • All-cause mortality was collected from first dose till death (Up to 20 months). Serious adverse events and non-serious adverse events were collected from first dose until 56 days after last dose of study therapy (Up to approximately 9 months). Data at cut-off is only for the single blind treatment period and is prior to the open label extension phase,

Additional Information

Bristol-Myers Squibb Study Director

Bristol-Myers Squibb

Phone: Please Email:

Email: Clinical.Trials@bms.com

Results disclosure agreements

• Principal investigator is a sponsor employee Bristol-Myers Squibb Co. agreements with investigators vary; constant is our right to embargo communications regarding trial results prior to public release for a period ≤60 days from submittal for review. We will not prohibit investigators from publishing but will prohibit the disclosure of previously undisclosed confidential information other than study results, and request postponement of single-center publications until after disclosure of the clinical trial's primary publication.
• Publication restrictions are in place

Restriction type: OTHER