One 100 mg capsule taken by mouth every 12 hours

Relief defined as reduction of severity from moderate to none, or severe to mild/none (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

Overall alleviation defined as both:

1. Any core symptom(s) that are none/mild (Likert 0 or 1) at baseline are none at 10 weeks, and
2. Any core symptom(s) that are moderate/severe (Likert 2 or 3) at baseline are none/mild at 10 weeks.

Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

This outcome was to assess the severity of the most bothersome symptom experienced by participants. Each symptom was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms) using the Core Symptoms Severity Scale.

Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

The PROMIS-Physical Function Short Form (SF) assesses difficulty level performing activities of daily living such as doing chores, climbing stairs, walking, and running errands. The assessment consists of 4 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to better physical function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher physical function T-score indicates better physical function.

The PROMIS Fatigue Score assesses level of fatigue and its interference on daily activities. The assessment consists of 7 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to more fatigue). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher fatigue T-score indicates greater fatigue.

The PROMIS-Fatigue Dyspnea-Severity Short Form assesses shortness of breath and its interference on daily activities. The assessment consists of 5 items (questions) scored on 4-point Likert scale with a 7-day recall period (higher scores correspond to worse symptoms). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Dyspnea-Severity T-score indicates worse symptoms.

The PROMIS-Cognitive Function Abilities Short Form assesses brain fog and its interference on daily activities. The assessment consists of 4 items scored on 5-point Likert scale with a 7-day recall period (higher scores indicate better cognitive function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Cognitive Function T-score indicates better cognitive function.

This outcome measures the difference in supine to standing systolic blood pressure (SBP) and diastolic blood pressure (DBP).

This outcome measures the difference in supine to standing heart rate.

Number of times participant is able to go from sitting (in an armless chair) to standing in 1 minute (sit to stand cycles).

The PGIS reflects a participant's perception about the overall severity of their disease symptoms, rated from 1 to 6 (1 = not present; 2 = very mild; 3 = mild; 4 = moderate; 5 = severe; 6 = extremely severe).

The PGIC reflects a participant's perception about the overall efficacy of treatment and their overall status since the start of the treatment, rated from 1 to 7 (1 = very much improved; 2 = much improved; 3 = minimally improved; 4 = no change; 5 = minimally worse; 6 = much worse; 7 = very much worse).

Core Symptoms Severity Scale Scores for each of the 6 core symptoms were summed to create a summative score. Each core symptom is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms). Summative score range: 0 to 18 (high scores correspond to greater severity).

Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).

Total of all reporting groups

Index COVID-19 infection was defined as the initial infection associated with subsequent onset of participant's postacute sequelae of SARS-CoV-2 infection.

Total COVID-19 infections was the participant-reported total number of COVID-19 infections before enrollment.

Other medications for acute infection include remdesivir, molnupiravir, and bebtelovimab.

Participant-reported comorbidities included onset before and after the index COVID-19 infection.

Participants receive placebo to match nirmatrelvir plus ritonavir (one 100 mg capsule) every 12 hours for 15 days, and attend follow-up visits through week 15.

This measure was to evaluate whether there is a difference between treatment with Paxlovid versus placebo on any of the 6 core symptoms of PASC at week 10 (adjusting for patients' baseline levels). Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).

Participants with symptoms data at day 15

Relief defined as reduction of severity from moderate to none, or severe to mild/none (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

Overall alleviation defined as both:

1. Any core symptom(s) that are none/mild (Likert 0 or 1) at baseline are none at 10 weeks, and
2. Any core symptom(s) that are moderate/severe (Likert 2 or 3) at baseline are none/mild at 10 weeks.

Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

This outcome was to assess the severity of the most bothersome symptom experienced by participants. Each symptom was assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms) using the Core Symptoms Severity Scale.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to the respective data collection time point.

Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

Relief defined as reduction of severity from moderate to none, or severe to mild/none for 2 consecutive weeks (≥ 2-point Likert score change). Likert score range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms.

The PROMIS-Physical Function Short Form (SF) assesses difficulty level performing activities of daily living such as doing chores, climbing stairs, walking, and running errands. The assessment consists of 4 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to better physical function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher physical function T-score indicates better physical function.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

The PROMIS Fatigue Score assesses level of fatigue and its interference on daily activities. The assessment consists of 7 items (questions) with each item scored on 5-point Likert scale (higher scores correspond to more fatigue). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher fatigue T-score indicates greater fatigue.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

The PROMIS-Fatigue Dyspnea-Severity Short Form assesses shortness of breath and its interference on daily activities. The assessment consists of 5 items (questions) scored on 4-point Likert scale with a 7-day recall period (higher scores correspond to worse symptoms). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Dyspnea-Severity T-score indicates worse symptoms.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

The PROMIS-Cognitive Function Abilities Short Form assesses brain fog and its interference on daily activities. The assessment consists of 4 items scored on 5-point Likert scale with a 7-day recall period (higher scores indicate better cognitive function). Scores are computed to a T-score metric, where 50 represents the mean for US general adult population and 10 is the standard deviation. A higher Cognitive Function T-score indicates better cognitive function.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

This outcome measures the difference in supine to standing systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

This outcome measures the difference in supine to standing heart rate.

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

Number of times participant is able to go from sitting (in an armless chair) to standing in 1 minute (sit to stand cycles).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10

The PGIS reflects a participant's perception about the overall severity of their disease symptoms, rated from 1 to 6 (1 = not present; 2 = very mild; 3 = mild; 4 = moderate; 5 = severe; 6 = extremely severe).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to the respective data collection time point.

The PGIC reflects a participant's perception about the overall efficacy of treatment and their overall status since the start of the treatment, rated from 1 to 7 (1 = very much improved; 2 = much improved; 3 = minimally improved; 4 = no change; 5 = minimally worse; 6 = much worse; 7 = very much worse).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to the respective data collection time point.

Core Symptoms Severity Scale Scores for each of the 6 core symptoms were summed to create a summative score. Each core symptom is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms). Summative score range: 0 to 18 (high scores correspond to greater severity).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to the respective data collection time point.

Each symptom (fatigue, brain fog, dyspnea, body aches, gastrointestinal symptoms, cardiovascular symptoms) is assessed on a 4-point Likert scale (range: 0 to 3; 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms; 3 = severe symptoms).

Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 15.

Participants receive placebo to match nirmatrelvir plus ritonavir (one 100 mg capsule) every 12 hours for 15 days, and attend follow-up visits through week 15.

Unrelated to intervention

Unrelated to intervention

Possibly related to intervention