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NCT05438602 · ClinicalTrials.gov registry record · Phase 2
A Study to Learn About the Study Medicines (Nirmatrelvir Plus Ritonavir) in People Aged 12 Years or Older With COVID-19 and a Compromised Immune System
A Phase 2 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 2
- Development phase
- 158
- Enrollment target
NCT05438602: Completed Phase 2 study, sponsored by Pfizer.
NCT05438602 is a Phase 2 study that has completed, run by Pfizer. The registered enrollment target is 158 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (19% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05438602, a Phase 2 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 158 participants
- Enrollment target
Study Summary
The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called Nirmatrelvir/Ritonavir) for the possible treatment of COVID-19. Patients with COVID-19 who have more difficulty in fighting against infections have a higher chance of severe illness. Such patients may benefit from longer treatment durations compared to the standard treatment regimen. The study is seeking participants who: * Have a confirmed COVID-19 infection * Are Immunocompromised * Experience onset of signs/symptoms attributable to the current COVID-19 infection within 5 days prior to screening and ≥1 signs/symptoms attributable to COVID-19 present on the day of randomization. In addition, this study will also evaluate the efficacy and safety of a second treatment course of nirmatrelvir/ritonavir in people who experience that their COVID-19 is flaring up within 14 days of having taken a 5-day treatment course of nirmatrelvir/ritonavir. For this group, the study is seeking participants who: * Have a confirmed COVID-19 infection * Experience a worsening of signs/symptoms after completing an initial 5-day course of nirmatrelvir/ritonavir * The worsening of COVID-19 symptoms must occur within 14 days after completion of the initial 5-day course of nirmatrelvir/ritonavir * Are Immunocompromised * Experience onset of signs/symptoms attributable to the current COVID-19 infection within 48 hours prior to screening and ≥1 signs/symptoms attributable to COVID-19 present on the day of randomization. All participants will be taking the study medicine for either 5, 10, or 15 days. The study medication will be taken by mouth 2 times a day. Participants will take part in this study for about 24 weeks. The first dose of study medication is taken at the study site and the rest at home. Selected participants will need to visit the study site at least 10 times during the study.
Primary Outcome
NP swab was collected by healthcare professional (HCP) from participants and were sent to the central laboratory for viral RNA level testing real-time reverse transcriptase-polymerase chain reaction(RT-PCR). Sustained was defined as NP swab SARS-CoV-2 RNA level not \>=2.0 log10 per milliliter (copies/mL) at any study visit (through Day 44) following the first study visit where the participant's NP swab SARS-CoV-2 RNA level \<LLOQ (\<2.0 log10 copies/mL).
Interventions
- DRUG Ritonavir
- DRUG Placebo for ritonavir
- DRUG Nirmatrelvir
- DRUG Placebo for nirmatrelvir
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 158 participants |
| Start Date | 2022-08-03 |
| Est. Completion | 2023-11-13 |
| Phase | Phase 2 |
What the finished NCT05438602 record still lists
NCT05438602 is an interventional study that assigns participants to a tested intervention. The registered 158 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 (19% higher).
The record links to 0 conditions, and to 4 interventions - of which Ritonavir is the first listed.
NCT05438602 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05438602 about?
NCT05438602 is a clinical study titled "A Study to Learn About the Study Medicines (Nirmatrelvir Plus Ritonavir) in People Aged 12 Years or Older With COVID-19 and a Compromised Immune System". The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called Nirmatrelvir/Ritonavir) for the possible treatment of COVID-19. Patients with COVID-19 who have more difficulty in fighting against infections have a higher chance of severe illness. Such patie...
What is the current status of trial NCT05438602?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 158 participants. The study started on 2022-08-03. Estimated completion is 2023-11-13.
What interventions are being tested in trial NCT05438602?
The interventions under investigation include: Ritonavir (DRUG), Placebo for ritonavir (DRUG), Nirmatrelvir (DRUG), Placebo for nirmatrelvir (DRUG).
Who is sponsoring clinical trial NCT05438602?
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 NCT05438602's enrollment target sits among peer trials
158 443rd of 2000 higher than 1,558 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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