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NCT05567952 · ClinicalTrials.gov registry record · Phase 2
A Study to Learn About a Repeat 5-Day Treatment With the Study Medicines (Called Nirmatrelvir/Ritonavir) in People 12 Years Old or Older With Return of COVID-19 Symptoms and SARS-CoV-2 Positivity After Finishing Treatment With Nirmatrelvir/Ritonavir
A Phase 2 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 2
- Development phase
- 436
- Enrollment target
NCT05567952: Completed Phase 2 study, sponsored by Pfizer.
NCT05567952 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 436 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (228% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05567952, a Phase 2 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 436 participants
- Enrollment target
Study Summary
The purpose of this study is to learn about the safety and effects of nirmatrelvir/ritonavir for the potential treatment of COVID-19 rebound. The study is seeking participants who: * Have completed treatment with nirmatrelvir/ritonavir * Have a rebound in COVID-19 symptoms * Are SARS-CoV-2 (COVID-19) positive All study medications will be taken 2 times a day by mouth for 5 days. The first dose of study medication is taken at the study clinic and the rest at home. We will examine the experiences of people receiving the study medicines to those who do not. This will help us determine if the study medicines are safe and effective. People taking part will be in this study for about 24 weeks. Enrolled participants will need to visit the study clinic at least 8 times during the study.
Primary Outcome
Baseline was defined as the latest measurement between Day -1 and Day 1, but post-dose samples that were collected within 1 hour post start of dosing were also treated as baseline. Samples with result "\< lower limit of quantification (LLOQ)" were imputed as 1.7 log10 copies/milliliter (mL), and samples with result "Not Detected" were imputed as 0.0 log10 copies/mL.
Interventions
- DRUG nirmatrelvir
- DRUG ritonavir
- DRUG placebo for nirmatrelvir
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 436 participants |
| Start Date | 2022-10-19 |
| Est. Completion | 2024-02-09 |
| Phase | Phase 2 |
What the finished NCT05567952 record still lists
NCT05567952 is an interventional study that assigns participants to a tested intervention. The registered 436 participants enrollment target is mid-sized for trials with a published cap, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (228% higher).
The record links to 0 conditions, and to 3 interventions - of which nirmatrelvir is the first listed.
NCT05567952 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05567952 about?
NCT05567952 is a clinical study titled "A Study to Learn About a Repeat 5-Day Treatment With the Study Medicines (Called Nirmatrelvir/Ritonavir) in People 12 Years Old or Older With Return of COVID-19 Symptoms and SARS-CoV-2 Positivity After Finishing Treatment With Nirmatrelvir/Ritonavir". The purpose of this study is to learn about the safety and effects of nirmatrelvir/ritonavir for the potential treatment of COVID-19 rebound. The study is seeking participants who: * Have completed treatment with nirmatrelvir/ritonavir * Have a rebound in COVID-19 symptoms * Are SARS-CoV-2 (COVID-...
What is the current status of trial NCT05567952?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 436 participants. The study started on 2022-10-19. Estimated completion is 2024-02-09.
What interventions are being tested in trial NCT05567952?
The interventions under investigation include: nirmatrelvir (DRUG), ritonavir (DRUG), placebo for nirmatrelvir (DRUG).
Who is sponsoring clinical trial NCT05567952?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05567952's enrollment target sits among peer trials
436 89th of 2000 higher than 1,911 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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