A Study on 2 Different Combination Tablets of Nirmatrelvir Plus Ritonavir to Compare Them With Marketed Paxlovid in Healthy Participants
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Phase
Phase 1
Status
Withdrawn
Study type
Interventional
Design
Randomized · None · Basic science
Enrollment
0actual
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Why the sponsor stopped it
Sponsor business decision to terminate study. Decision not due to major safety concerns or requests from any regulatory authorities.
As filed on the registry record, in the sponsor's own words.
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2025-08-15 | estimated | When the study began enrolling |
| Primary completion | 2025-12-09 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-12-09 | estimated | The whole study's end, after follow-up |
| First posted | 2024-05-02 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-12-26 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Biological Availability
- Healthy Participants
Interventions
- Drug: Paxlovid — also filed as Nirmatrelvir/ritonavir commercial tablets
- Drug: Paxlovid — also filed as Nirmatrelvir/ritonavir commercial tablets
- Drug: Nirmatrelvir/ritonavir — also filed as Nirmatrelvir/ritonavir FDC test tablets formulation 1
- Drug: Nirmatrelvir/ritonavir — also filed as Nirmatrelvir/ritonavir FDC test tablets formulation 2
Primary outcomes
what the primary-completion date above is the date OFArea under curve (AUC) from time zero to 48 hours post dose (nirmatrelvir)
measured 0 , 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 16, 24 and 48 hours
Peak plasma concentration (Cmax) for nirmatrelvir
measured 0 , 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 16, 24 and 48 hours
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