Trial · NCT05576662
Paxlovid for Treatment of Long Covid
NCT05576662, Phase 2, Completed, Stanford University; results first posted 2024-09-25
3 sourcestrials-2026-11-12-0.5.0
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ConductScience Library. Paxlovid for Treatment of Long Covid. Trials, record NCT05576662. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT05576662
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Trial
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
- Title
- Paxlovid for Treatment of Long Covid
- NCT number
- NCT05576662
- Status
- Completed
- Phases
- Phase 2
- Enrollment
- 168 participants, actual
- Lead sponsor
- Stanford University
- Conditions
- Post-acute Sequelae of SARS-CoV-2 Infection, Long COVID
- Interventions
- Nirmatrelvir, Placebo, Ritonavir
- First posted
- 2022-10-12
- Last updated
- 2025-09-04
- Results first posted
- 2024-09-25
Source ClinicalTrials.gov
Registered outcomes18
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description |
|---|---|---|---|
| Primary | Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Week 10 | 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). |
| Secondary | Number of Participants With No, Mild, Moderate, or Severe Symptoms at Day 15 According to the Core Symptoms Severity Scale Score | Day 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). |
| Secondary | Number of Participants Reporting Relief of at Least One Core Symptom for 2 Weeks | Baseline through week 10, assessed at week 10 | 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. |
| Secondary | Number of Participants With Overall Alleviation for 2 Weeks | Baseline through week 10, assessed at 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. |
| Secondary | Number of Participants With No, Mild, Moderate, or Severe Symptoms of Their Most Bothersome Symptom | Assessed at weeks 5, 10, and 15 | 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. |
| Secondary | Time to Relief of the 6 Core Symptoms | Up to 15 weeks | 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. |
| Secondary | Time to Relief of the Most Bothersome Symptom | Up to 15 weeks | 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. |
| Secondary | Change in Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function T-Score | Baseline and week 10 | 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. |
| Secondary | Change in PROMIS Fatigue T-Score | Baseline and 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. |
| Secondary | Change in PROMIS Dyspnea-Severity T-Score | Baseline and 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. |
1 to 10 of 18Source ClinicalTrials.gov
See all 18 registered outcomesOutcomes18
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as |
|---|---|---|---|---|---|
| PRIMARY | Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Week 10 | If participants did not have week 10 data, week 9 data were used when available; otherwise missing data were imputed for statistical analysis. | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | Number of Participants With No, Mild, Moderate, or Severe Symptoms at Day 15 According to the Core Symptoms Severity Scale Score | Day 15 | Participants with symptoms data at day 15 | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | Number of Participants Reporting Relief of at Least One Core Symptom for 2 Weeks | Baseline through week 10, assessed at week 10 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10 | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | Number of Participants With Overall Alleviation for 2 Weeks | Baseline through week 10, assessed at week 10 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10 | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | Number of Participants With No, Mild, Moderate, or Severe Symptoms of Their Most Bothersome Symptom | Assessed at weeks 5, 10, and 15 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to the respective data collection time point. | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | Time to Relief of the 6 Core Symptoms | Up to 15 weeks | weeks | MEDIAN | |
| SECONDARY | Time to Relief of the Most Bothersome Symptom | Up to 15 weeks | weeks | MEDIAN | |
| SECONDARY | Change in Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function T-Score | Baseline and week 10 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10 | T-score | MEAN |
| SECONDARY | Change in PROMIS Fatigue T-Score | Baseline and week 10 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10 | T-score | MEAN |
| SECONDARY | Change in PROMIS Dyspnea-Severity T-Score | Baseline and week 10 | Missing data were imputed for statistical analysis, including for participants who were withdrawn prior to week 10 | T-score | MEAN |
1 to 10 of 18Source ClinicalTrials.gov
See all 18 outcomesResults by group212
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units |
|---|---|---|---|---|---|
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Nirmatrelvir Plus Ritonavir | Fatigue - no symptoms | 3 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Placebo Plus Ritonavir | Fatigue - no symptoms | 4 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Nirmatrelvir Plus Ritonavir | Fatigue - mild symptoms | 22 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Placebo Plus Ritonavir | Fatigue - mild symptoms | 17 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Nirmatrelvir Plus Ritonavir | Fatigue - moderate symptoms | 43 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Placebo Plus Ritonavir | Fatigue - moderate symptoms | 17 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Nirmatrelvir Plus Ritonavir | Fatigue - severe symptoms | 31 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Placebo Plus Ritonavir | Fatigue - severe symptoms | 11 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Nirmatrelvir Plus Ritonavir | Brain fog - no symptoms | 11 | Participants | |
| Number of Participants With No, Mild, Moderate, or Severe Symptoms at Week 10 According to the Core Symptoms Severity Scale Score | Placebo Plus Ritonavir | Brain fog - no symptoms | 8 | Participants |
1 to 10 of 212Source ClinicalTrials.gov
See all 212 results by groupParticipant flow6
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted |
|---|---|---|---|---|
| Overall Study | STARTED | Nirmatrelvir Plus Ritonavir | 102 | |
| Overall Study | STARTED | Placebo Plus Ritonavir | 53 | |
| Overall Study | COMPLETED | Nirmatrelvir Plus Ritonavir | 98 | |
| Overall Study | COMPLETED | Placebo Plus Ritonavir | 49 | |
| Overall Study | NOT COMPLETED | Nirmatrelvir Plus Ritonavir | 4 | |
| Overall Study | NOT COMPLETED | Placebo Plus Ritonavir | 4 |
Source ClinicalTrials.gov
Adverse events76
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
| Type | Event | Organ system | Group | Affected | At risk | Events |
|---|---|---|---|---|---|---|
| other | palpitations | Cardiac disorders | Nirmatrelvir Plus Ritonavir | 12 | 102 | |
| other | palpitations | Cardiac disorders | Placebo Plus Ritonavir | 7 | 53 | |
| other | tachycardia | Cardiac disorders | Nirmatrelvir Plus Ritonavir | 2 | 102 | |
| other | tachycardia | Cardiac disorders | Placebo Plus Ritonavir | 4 | 53 | |
| other | vision blurred | Eye disorders | Nirmatrelvir Plus Ritonavir | 4 | 102 | |
| other | vision blurred | Eye disorders | Placebo Plus Ritonavir | 4 | 53 | |
| other | abdominal discomfort | Gastrointestinal disorders | Nirmatrelvir Plus Ritonavir | 9 | 102 | |
| other | abdominal discomfort | Gastrointestinal disorders | Placebo Plus Ritonavir | 0 | 53 | |
| other | abdominal distension | Gastrointestinal disorders | Nirmatrelvir Plus Ritonavir | 6 | 102 | |
| other | abdominal distension | Gastrointestinal disorders | Placebo Plus Ritonavir | 3 | 53 |
1 to 10 of 76Source ClinicalTrials.gov
See all 76 adverse eventsAdverse event totals6
The totals the trial posted for each group.
| Total | Group | Affected | At risk |
|---|---|---|---|
| Total, all-cause mortality | Nirmatrelvir Plus Ritonavir | 0 | 102 |
| Total, all-cause mortality | Placebo Plus Ritonavir | 0 | 53 |
| Total, other adverse events | Nirmatrelvir Plus Ritonavir | 100 | 102 |
| Total, other adverse events | Placebo Plus Ritonavir | 48 | 53 |
| Total, serious adverse events | Nirmatrelvir Plus Ritonavir | 3 | 102 |
| Total, serious adverse events | Placebo Plus Ritonavir | 1 | 53 |
Source ClinicalTrials.gov
Papers2
The papers the trial lists on ClinicalTrials.gov.
Grants0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
None in this release.
Trial comparisons4
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|---|
| Nirmatrelvir Plus Ritonavir vs Placebo Plus Ritonavir: Number of Participants With Overall Alleviation for 2 Weeks | Trial comparisons |
| Nirmatrelvir Plus Ritonavir vs Placebo Plus Ritonavir: deaths from any cause | Trial comparisons |
| Nirmatrelvir Plus Ritonavir vs Placebo Plus Ritonavir: Number of Participants Reporting Relief of at Least One Core Symptom for 2 Weeks | Trial comparisons |
| Nirmatrelvir Plus Ritonavir vs Placebo Plus Ritonavir: serious adverse events | Trial comparisons |
Tests0
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
None in this release.
Data dates
The day each source was copied for this release.
Sources 3
- ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
- ClinicalTrials.govNo license stated
- NIH RePORTER's clinical studies and project filesPublic domain
Each source's terms
- ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
- ClinicalTrials.govnone stated
- NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)
ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
For software
Read this trial from software.
The record and each of its lists are JSON, twenty rows a page. No key.
GET https://conductscience.org/api/trials/v1/NCT05576662
GET https://conductscience.org/api/trials/v1/NCT05576662/results?page=2