Trial Outcomes & Findings for A Study of a Potential Oral Treatment to Prevent COVID-19 in Adults Who Are Exposed to Household Member(s) With a Confirmed Symptomatic COVID-19 Infection (NCT NCT05047601)

Results Overview

Percentage of participants who developed symptomatic Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) or Rapid Antigen Test (RAT) confirmed SARS-Cov-2 infection were reported in this outcome measure. Index case was defined as participants with symptomatic COVID-19.

Recruitment status

COMPLETED

Study phase

PHASE2/PHASE3

Target enrollment

2954 participants

Primary outcome timeframe

From Day 1 to Day 14

Results posted on

2023-05-06

Participant Flow

Participants who had a negative screening severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen test result and were asymptomatic household contacts of individuals who were symptomatic and recently tested positive for SARS-CoV-2, were included in the study.

A total of 2880 participants were screened. Out of which, 122 participants were screen failures. 22 participants were not screen failures and were not randomized. 2736 participants were randomized and 2721 participants received study drug.

Participant milestones

Participant milestones
Measure	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days Participants were randomized to receive nirmatrelvir 300 milligrams (mg) and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.	Placebo Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.
Overall Study STARTED	921	917	898
Overall Study Treated	913	911	897
Overall Study COMPLETED	877	864	863
Overall Study NOT COMPLETED	44	53	35

Reasons for withdrawal

Reasons for withdrawal
Measure	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days Participants were randomized to receive nirmatrelvir 300 milligrams (mg) and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.	Placebo Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.
Overall Study Lost to Follow-up	9	11	7
Overall Study Withdrawal by Subject	25	36	23
Overall Study Other	10	6	5

Baseline Characteristics

A Study of a Potential Oral Treatment to Prevent COVID-19 in Adults Who Are Exposed to Household Member(s) With a Confirmed Symptomatic COVID-19 Infection

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=921 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=917 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.	Placebo n=898 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Total n=2736 Participants Total of all reporting groups
Age, Continuous	43.92 Years STANDARD_DEVIATION 14.88 • n=5 Participants	42.85 Years STANDARD_DEVIATION 15.02 • n=7 Participants	42.39 Years STANDARD_DEVIATION 14.36 • n=5 Participants	43.06 Years STANDARD_DEVIATION 14.77 • n=4 Participants
Sex: Female, Male Female	502 Participants n=5 Participants	479 Participants n=7 Participants	474 Participants n=5 Participants	1455 Participants n=4 Participants
Sex: Female, Male Male	419 Participants n=5 Participants	438 Participants n=7 Participants	424 Participants n=5 Participants	1281 Participants n=4 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	664 Participants n=5 Participants	642 Participants n=7 Participants	643 Participants n=5 Participants	1949 Participants n=4 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	257 Participants n=5 Participants	275 Participants n=7 Participants	255 Participants n=5 Participants	787 Participants n=4 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) American Indian or Alaska Native	58 Participants n=5 Participants	52 Participants n=7 Participants	49 Participants n=5 Participants	159 Participants n=4 Participants
Race (NIH/OMB) Asian	8 Participants n=5 Participants	15 Participants n=7 Participants	11 Participants n=5 Participants	34 Participants n=4 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	0 Participants n=4 Participants
Race (NIH/OMB) Black or African American	139 Participants n=5 Participants	136 Participants n=7 Participants	132 Participants n=5 Participants	407 Participants n=4 Participants
Race (NIH/OMB) White	714 Participants n=5 Participants	711 Participants n=7 Participants	704 Participants n=5 Participants	2129 Participants n=4 Participants
Race (NIH/OMB) More than one race	1 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants	3 Participants n=4 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	2 Participants n=7 Participants	1 Participants n=5 Participants	4 Participants n=4 Participants

PRIMARY outcome

Timeframe: From Day 1 to Day 14

Population: Modified Intent-To-Treat (mITT) population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

Percentage of participants who developed symptomatic Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) or Rapid Antigen Test (RAT) confirmed SARS-Cov-2 infection were reported in this outcome measure. Index case was defined as participants with symptomatic COVID-19.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants Who Developed Symptomatic RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Negative RT-PCR at Baseline	3.929 Percentage of participants	2.607 Percentage of participants	2.410 Percentage of participants

SECONDARY outcome

Timeframe: From start of study intervention (Day 1) up to end of safety follow-up (Day 38)

Population: Safety analysis set included all participants randomly assigned to study intervention and who received at least 1 dose of study intervention.

An AE was defined as any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. An SAE was defined as any untoward medical occurrence at any dose that resulted in any of the following outcomes: death; life-threatening ; required inpatient hospitalization or prolongation of existing hospitalization; persistent or significant disability/incapacity ; congenital anomaly/birth defect; or that was considered as an important medical event. TEAEs were defined as events that started on or after the study medication start date and time. AEs included both serious and all non-serious adverse events. AEs that led to study discontinuation and AEs that led to discontinuation of study intervention and then continued study were also reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Placebo n=898 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=912 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=911 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious AEs and AEs Leading to Study and Study Drug Discontinuation TEAEs	195 Participants	218 Participants	212 Participants
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious AEs and AEs Leading to Study and Study Drug Discontinuation SAEs	2 Participants	3 Participants	1 Participants
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious AEs and AEs Leading to Study and Study Drug Discontinuation AEs led to discontinuation of study	0 Participants	0 Participants	0 Participants
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious AEs and AEs Leading to Study and Study Drug Discontinuation AEs led to discontinue study intervention and continued study	14 Participants	10 Participants	11 Participants

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: Modified Intent-To-Treat (mITT2) population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline and were at increased risk of severe COVID-19 illness.

Percentage of participants who had a symptomatic RT-PCR or RAT confirmed SARS-Cov-2 infection were reported in this outcome measure. The risk factors associated with severe covid-19 illness included age greater than or equal to 60 years, body mass index greater than 25, social history of smoking and presence of comorbidities. Index case was defined as participants with symptomatic COVID-19.

Outcome measures

Outcome measures
Measure	Placebo n=606 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=627 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=605 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants Who Developed Symptomatic RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Negative RT-PCR at Baseline With Increased Risk of Severe COVID-19 Illness	3.465 Percentage of participants	2.871 Percentage of participants	2.645 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 28

Population: mITT2 population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline and were at increased risk of severe COVID-19 illness.

The risk factors associated with severe covid-19 illness included age greater than or equal to 60 years, body mass index greater than 25, social history of smoking and presence of comorbidities.

Outcome measures

Outcome measures
Measure	Placebo n=606 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=627 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=605 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With COVID-19 Related Hospitalization or Death From Any Cause Through Day 28: Among Participants With Negative RT-PCR at Baseline With Increased Risk of Severe COVID-19 Illness	0.165 Percentage of participants	0 Percentage of participants	0 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

Percentage of participants who had asymptomatic RT-PCR or RAT confirmed SARS-CoV-2 infection through day 14 among participants with negative RT-PCR at baseline were reported in this outcome measure. Index case was defined as participants with symptomatic COVID-19.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With Asymptomatic RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Negative RT-PCR at Baseline	3.095 Percentage of participants	2.014 Percentage of participants	1.928 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

Number of days between first dose and confirmation of the SARS-CoV-2 infection by RT-PCR or RAT was reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Time to RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Negative RT-PCR at Baseline	NA Days Median and the corresponding 95% CI could not be calculated as the proportion of participants who achieved the event were low.	NA Days Median and the corresponding 95% CI could not be calculated as the proportion of participants who achieved the event were low.	NA Days Median and the corresponding 95% CI could not be calculated as the proportion of participants who achieved the event were low.

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: mITT1 population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a positive RT-PCR result at baseline.

Percentage of participants with a positive RT-PCR result at baseline who had a symptomatic SARS-CoV-2 infection confirmed by RAT or RT-PCR through Day 14 were reported in this outcome measure. Index case was defined as participants with symptomatic COVID-19.

Outcome measures

Outcome measures
Measure	Placebo n=29 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=38 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=48 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With Symptomatic RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Positive RT-PCR at Baseline	37.931 Percentage of participants	28.947 Percentage of participants	45.833 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: Modified Intent-To-Treat (mITT3) population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative, positive or missing RT-PCR result at baseline.

Percentage of participants with a negative, positive, or missing RT-PCR result at baseline, who had a symptomatic SARS-CoV-2 infection confirmed by RAT or RT-PCR through Day 14 were reported in this outcome measure. Index case was defined as participants with symptomatic COVID-19.

Outcome measures

Outcome measures
Measure	Placebo n=873 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=889 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=887 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With Symptomatic RT-PCR or RAT Confirmed SARS-CoV-2 Infection Through Day 14: Among Participants With Negative, Positive or Missing RT-PCR at Baseline	5.269 Percentage of Participants	3.712 Percentage of Participants	4.848 Percentage of Participants

SECONDARY outcome

Timeframe: From Day 1 to Day 28

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

Participants were categorized according to severity of signs and symptoms as no, mild, moderate, severe in this outcome measure. The 12 signs and symptoms included stuffy or runny nose, sore throat, shortness of breath or difficulty breathing, cough, low energy or tiredness, muscle or body aches, headache, chills or shivering, feeling hot or feverish, nausea, vomiting, diarrhea. Participants recorded their daily severity rating of their symptoms over the past 24 hours based on a 4-point scale in which 0 was reported if no symptoms were present; 1 if mild; 2 if moderate; and 3 if severe.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With no, Mild, Moderate, or Severe Signs and Symptoms Attributed to COVID-19 Through Day 28: Among Participants With Negative RT-PCR at Baseline No	81.667 Percentage of participants	81.517 Percentage of participants	83.373 Percentage of participants
Percentage of Participants With no, Mild, Moderate, or Severe Signs and Symptoms Attributed to COVID-19 Through Day 28: Among Participants With Negative RT-PCR at Baseline Mild	7.619 Percentage of participants	7.820 Percentage of participants	8.193 Percentage of participants
Percentage of Participants With no, Mild, Moderate, or Severe Signs and Symptoms Attributed to COVID-19 Through Day 28: Among Participants With Negative RT-PCR at Baseline Moderate	7.143 Percentage of participants	6.872 Percentage of participants	5.060 Percentage of participants
Percentage of Participants With no, Mild, Moderate, or Severe Signs and Symptoms Attributed to COVID-19 Through Day 28: Among Participants With Negative RT-PCR at Baseline Severe	2.738 Percentage of participants	2.133 Percentage of participants	2.048 Percentage of participants
Percentage of Participants With no, Mild, Moderate, or Severe Signs and Symptoms Attributed to COVID-19 Through Day 28: Among Participants With Negative RT-PCR at Baseline Missing	0.833 Percentage of participants	1.659 Percentage of participants	1.325 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 28

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline. Here, ''Overall Number of Participants Analyzed'' signifies participants evaluable for this outcome measure.

This outcome measure has been reported in terms of number of participants according to days of symptomatic SARS-CoV-2 infection through Day 28.

Outcome measures

Outcome measures
Measure	Placebo n=33 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=22 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=20 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 13 Days of Symptoms	2 Participants	1 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 14 Days of Symptoms	0 Participants	1 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 18 Days of Symptoms	0 Participants	2 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 20 Days of Symptoms	0 Participants	1 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 11 Days of Symptoms	1 Participants	0 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 12 Days of Symptoms	4 Participants	2 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 1 Day of Symptoms	2 Participants	1 Participants	7 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 2 Days of Symptoms	1 Participants	2 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 3 Days of Symptoms	4 Participants	0 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 4 Days of Symptoms	2 Participants	5 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 5 Days of Symptoms	3 Participants	1 Participants	3 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 6 Days of Symptoms	3 Participants	0 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 7 Days of Symptoms	4 Participants	3 Participants	4 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 8 Days of Symptoms	5 Participants	2 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 9 Days of Symptoms	1 Participants	0 Participants	1 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 10 Days of Symptoms	1 Participants	0 Participants	0 Participants
Number of Days of Symptomatic RT-PCR or RAT Confirmed SARS-CoV- 2 Infection Through Day 28: Among Participants With Negative RT-PCR at Baseline 26 Days of Symptoms	0 Participants	1 Participants	0 Participants

SECONDARY outcome

Timeframe: Day 1: 1 hour post dose; Day 5: 2 hours pre-dose

Population: Safety analysis set included all participants randomly assigned to study intervention and who received at least 1 dose of study intervention. This outcome measure was not planned to be analyzed for placebo arm. Here, ''Overall Number of Participants Analyzed'' signifies participants evaluable for this outcome measure and ''Number Analyzed'' signifies participants evaluable at specific time points.

Outcome measures

Outcome measures
Measure	Placebo Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=476 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=476 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Plasma Concentration Versus Time Summary of Nirmatrelvir (PF-07321332) Day 5 (2 hours pre-dose)	—	1688 Nanograms per milliliter Standard Deviation 2093.3	1657 Nanograms per milliliter Standard Deviation 2068.2
Plasma Concentration Versus Time Summary of Nirmatrelvir (PF-07321332) Day 1 (1 hour post-dose)	—	1489 Nanograms per milliliter Standard Deviation 1481.4	1472 Nanograms per milliliter Standard Deviation 1488.2

SECONDARY outcome

Timeframe: From Day 1 to Day 38

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

Percentage of participants with death (all-cause) event were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Percentage of Participants With Death Event Through Day 38: Among Participants With Negative RT-PCR at Baseline	0 Percentage of participants	0 Percentage of participants	0 Percentage of participants

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline. Here 'Number Analyzed' signifies participants evaluable for the specific time points.

Nasal samples were collected to estimate the viral load in terms of logarithm to base 10 (log10) copies per milliliter in participants with negative RT-PCR at baseline and were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 1	0.038 Log 10 copies per milliliter Standard Deviation 0.253	0.042 Log 10 copies per milliliter Standard Deviation 0.265	0.035 Log 10 copies per milliliter Standard Deviation 0.241
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 2	0.108 Log 10 copies per milliliter Standard Deviation 0.611	0.078 Log 10 copies per milliliter Standard Deviation 0.523	0.053 Log 10 copies per milliliter Standard Deviation 0.409
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 3	0.147 Log 10 copies per milliliter Standard Deviation 0.760	0.090 Log 10 copies per milliliter Standard Deviation 0.586	0.048 Log 10 copies per milliliter Standard Deviation 0.374
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 4	0.165 Log 10 copies per milliliter Standard Deviation 0.859	0.081 Log 10 copies per milliliter Standard Deviation 0.537	0.057 Log 10 copies per milliliter Standard Deviation 0.409
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 5	0.217 Log 10 copies per milliliter Standard Deviation 1.063	0.079 Log 10 copies per milliliter Standard Deviation 0.528	0.074 Log 10 copies per milliliter Standard Deviation 0.573
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 6	0.189 Log 10 copies per milliliter Standard Deviation 0.978	0.074 Log 10 copies per milliliter Standard Deviation 0.575	0.090 Log 10 copies per milliliter Standard Deviation 0.670
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 7	0.186 Log 10 copies per milliliter Standard Deviation 0.883	0.088 Log 10 copies per milliliter Standard Deviation 0.586	0.053 Log 10 copies per milliliter Standard Deviation 0.536
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 8	0.159 Log 10 copies per milliliter Standard Deviation 0.860	0.096 Log 10 copies per milliliter Standard Deviation 0.627	0.081 Log 10 copies per milliliter Standard Deviation 0.669
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 9	0.135 Log 10 copies per milliliter Standard Deviation 0.784	0.094 Log 10 copies per milliliter Standard Deviation 0.672	0.062 Log 10 copies per milliliter Standard Deviation 0.596
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 10	0.133 Log 10 copies per milliliter Standard Deviation 0.725	0.080 Log 10 copies per milliliter Standard Deviation 0.616	0.064 Log 10 copies per milliliter Standard Deviation 0.590
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 11	0.115 Log 10 copies per milliliter Standard Deviation 0.707	0.103 Log 10 copies per milliliter Standard Deviation 0.673	0.053 Log 10 copies per milliliter Standard Deviation 0.511
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 12	0.103 Log 10 copies per milliliter Standard Deviation 0.662	0.106 Log 10 copies per milliliter Standard Deviation 0.748	0.051 Log 10 copies per milliliter Standard Deviation 0.447
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 13	0.117 Log 10 copies per milliliter Standard Deviation 0.714	0.085 Log 10 copies per milliliter Standard Deviation 0.642	0.052 Log 10 copies per milliliter Standard Deviation 0.425
Viral Load in Nasal Samples Over Time: Among Participants With Negative RT-PCR at Baseline Day 14	0.146 Log 10 copies per milliliter Standard Deviation 0.798	0.108 Log 10 copies per milliliter Standard Deviation 0.717	0.035 Log 10 copies per milliliter Standard Deviation 0.386

SECONDARY outcome

Timeframe: From Day 1 to Day 14

Population: mITT1 population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a positive RT-PCR result at baseline. Here 'Number Analyzed' signifies participants evaluable for the specific time points.

Nasal samples were collected to estimate the viral load in terms of logarithm to base 10 (log10) copies per milliliter in participants with positive RT-PCR at baseline and were reported in this outcome measure.

Outcome measures

Outcome measures
Measure	Placebo n=29 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=38 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=48 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 1	4.837 Log 10 copies per milliliter Standard Deviation 1.577	4.870 Log 10 copies per milliliter Standard Deviation 2.041	4.470 Log 10 copies per milliliter Standard Deviation 1.542
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 2	3.104 Log 10 copies per milliliter Standard Deviation 2.909	3.286 Log 10 copies per milliliter Standard Deviation 2.534	2.724 Log 10 copies per milliliter Standard Deviation 2.208
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 3	3.255 Log 10 copies per milliliter Standard Deviation 2.702	2.880 Log 10 copies per milliliter Standard Deviation 2.641	2.051 Log 10 copies per milliliter Standard Deviation 2.212
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 4	2.721 Log 10 copies per milliliter Standard Deviation 2.640	2.600 Log 10 copies per milliliter Standard Deviation 2.427	1.514 Log 10 copies per milliliter Standard Deviation 2.064
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 5	2.994 Log 10 copies per milliliter Standard Deviation 2.677	1.470 Log 10 copies per milliliter Standard Deviation 2.057	1.413 Log 10 copies per milliliter Standard Deviation 1.745
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 6	2.466 Log 10 copies per milliliter Standard Deviation 2.561	1.065 Log 10 copies per milliliter Standard Deviation 1.656	0.997 Log 10 copies per milliliter Standard Deviation 1.696
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 7	1.478 Log 10 copies per milliliter Standard Deviation 2.212	1.199 Log 10 copies per milliliter Standard Deviation 1.747	0.913 Log 10 copies per milliliter Standard Deviation 1.762
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 8	1.072 Log 10 copies per milliliter Standard Deviation 1.663	1.212 Log 10 copies per milliliter Standard Deviation 1.829	0.942 Log 10 copies per milliliter Standard Deviation 1.908
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 9	1.103 Log 10 copies per milliliter Standard Deviation 1.545	1.169 Log 10 copies per milliliter Standard Deviation 1.852	0.766 Log 10 copies per milliliter Standard Deviation 1.858
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 10	0.965 Log 10 copies per milliliter Standard Deviation 1.514	0.819 Log 10 copies per milliliter Standard Deviation 1.656	0.541 Log 10 copies per milliliter Standard Deviation 1.605
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 11	0.707 Log 10 copies per milliliter Standard Deviation 1.116	0.623 Log 10 copies per milliliter Standard Deviation 1.170	0.603 Log 10 copies per milliliter Standard Deviation 1.044
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 12	0.436 Log 10 copies per milliliter Standard Deviation 0.919	0.532 Log 10 copies per milliliter Standard Deviation 1.136	0.670 Log 10 copies per milliliter Standard Deviation 1.204
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 13	0.361 Log 10 copies per milliliter Standard Deviation 0.770	0.413 Log 10 copies per milliliter Standard Deviation 1.098	0.313 Log 10 copies per milliliter Standard Deviation 1.018
Viral Load in Nasal Samples Over Time: Among Participants With Positive RT-PCR at Baseline Day 14	0.358 Log 10 copies per milliliter Standard Deviation 0.735	0.284 Log 10 copies per milliliter Standard Deviation 1.040	0.345 Log 10 copies per milliliter Standard Deviation 0.808

SECONDARY outcome

Timeframe: From Day 1 to Day 28

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

This outcome measure has been presented in terms of participants according to number of days of hospitalization and in ICU as 0 days and more than or equal to 1 day.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Number of Days of Hospitalization and Intensive Care Unit (ICU) Stay: Among Participants With Negative RT-PCR at Baseline ICU Visits: 0 Day	840 Participants	844 Participants	830 Participants
Number of Days of Hospitalization and Intensive Care Unit (ICU) Stay: Among Participants With Negative RT-PCR at Baseline ICU Visits: More than or equal to 1 day	0 Participants	0 Participants	0 Participants
Number of Days of Hospitalization and Intensive Care Unit (ICU) Stay: Among Participants With Negative RT-PCR at Baseline Hospitalization Visits: 0 Day	839 Participants	844 Participants	830 Participants
Number of Days of Hospitalization and Intensive Care Unit (ICU) Stay: Among Participants With Negative RT-PCR at Baseline Hospitalization Visits: More than or equal to 1 day	1 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: From Day 1 to Day 28

Population: mITT population included all participants randomly assigned to study intervention who received at least 1 dose of study intervention and had a negative RT-PCR result at baseline.

In this outcome measure number of COVID-19 related medical visits per day were reported. Number of medical visits per day = number of medical visits/number of days follow up through day 28 visit or the last collection date on or before day 28, if day 28 visit was missing.

Outcome measures

Outcome measures
Measure	Placebo n=840 Participants Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=844 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=830 Participants Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.
Number of COVID-19 Related Medical Visits Through Day 28: Among Participants With Negative RT-PCR at Baseline	0.0066 Medical visits per day Standard Deviation 0.0182	0.0067 Medical visits per day Standard Deviation 0.0200	0.0057 Medical visits per day Standard Deviation 0.0201

Adverse Events

Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days

Serious events: 3 serious events

Other events: 176 other events

Deaths: 0 deaths

Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days

Serious events: 1 serious events

Other events: 173 other events

Deaths: 0 deaths

Placebo

Serious events: 2 serious events

Other events: 152 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=912 participants at risk Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=911 participants at risk Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.	Placebo n=898 participants at risk Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.
Hepatobiliary disorders Cholecystitis acute	0.11% 1/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Infections and infestations COVID-19 pneumonia	0.11% 1/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.11% 1/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.11% 1/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Injury, poisoning and procedural complications Overdose	0.00% 0/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.11% 1/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Injury, poisoning and procedural complications Road traffic accident	0.11% 1/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Injury, poisoning and procedural complications Tibia fracture	0.11% 1/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.00% 0/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.

Other adverse events

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
Publication restrictions are in place

Restriction type: OTHER

Measure	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 5 Days n=912 participants at risk Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 5, followed by matching placebo every 12 hours from Day 6 through Day 10.	Nirmatrelvir (PF-07321332) 300 mg + Ritonavir 100 mg 10 Days n=911 participants at risk Participants were randomized to receive nirmatrelvir 300 mg and ritonavir 100 mg orally every 12 hours from Day 1 to 10.	Placebo n=898 participants at risk Participants were randomized to receive placebo matched to nirmatrelvir/ritonavir every 12 hours for 10 days from Day 1 through Day 10.
Gastrointestinal disorders Diarrhoea	2.5% 23/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	2.4% 22/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.7% 15/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Gastrointestinal disorders Nausea	1.8% 16/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.3% 12/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.6% 14/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
General disorders Asthenia	1.1% 10/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.77% 7/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.9% 17/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Infections and infestations COVID-19	3.0% 27/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	2.9% 26/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	4.0% 36/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Infections and infestations Nasopharyngitis	1.4% 13/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.99% 9/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.67% 6/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Infections and infestations Upper respiratory tract infection	2.2% 20/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.9% 17/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	2.0% 18/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Investigations Activated partial thromboplastin time prolonged	1.2% 11/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.5% 14/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	2.4% 22/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Investigations Alanine aminotransferase increased	0.22% 2/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.66% 6/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.2% 11/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Investigations Blood creatine phosphokinase increased	1.3% 12/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.6% 15/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.4% 13/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Investigations Blood thyroid stimulating hormone increased	1.2% 11/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.88% 8/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.1% 10/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Investigations Fibrin D dimer increased	2.0% 18/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.4% 13/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.45% 4/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Nervous system disorders Dysgeusia	5.9% 54/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	6.8% 62/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.67% 6/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Nervous system disorders Headache	1.6% 15/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.9% 17/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	3.2% 29/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Respiratory, thoracic and mediastinal disorders Cough	1.1% 10/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.22% 2/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.3% 12/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.
Respiratory, thoracic and mediastinal disorders Nasal congestion	0.44% 4/912 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	0.33% 3/911 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.	1.1% 10/898 • From Day 1 to Day 38 Same event may appear as both SAE and non-SAE but are distinct events. An event may be categorized as serious in 1 participant and non-serious in another, or a participant may have experienced both SAE and non-SAE. Safety population comprised of all participants who received at least 1 dose of study intervention during the study.