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NCT04644029 · ClinicalTrials.gov registry record · Phase 3
Oral ISL QM as PrEP in Cisgender Women at High Risk for HIV-1 Infection (MK-8591-022)
A Phase 3 study, sponsored by Merck Sharp & Dohme.
- Terminated
- Registry status
- Phase 3
- Development phase
- 730
- Enrollment target
NCT04644029: Clinical Trial Phase 3 study, sponsored by Merck Sharp & Dohme.
NCT04644029 is a Phase 3 study that was terminated before completion, run by Merck Sharp & Dohme. The registered enrollment target is 730 participants, roughly in line with the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04644029, a Phase 3 study, was terminated before completion, sponsored by Merck Sharp & Dohme.
- TERMINATED
- Registry status
- Phase 3
- Development phase
- 730 participants
- Enrollment target
Study Summary
This study will evaluate whether oral islatravir (ISL) is effective in preventing Human Immunodeficiency Virus Type 1 (HIV-1) infection in women at high-risk for HIV-1 infection. The study will compare oral ISL taken once a month with standard-of-care medication for prevention of HIV-1 infection, emtricitabine/tenofovir disoproxil (FTC/TDF), taken once per day. The primary hypothesis is that oral ISL is more effective than FTC/TDF at reducing the incidence rate per year of confirmed HIV-1 infections.
Primary Outcome
Incidence rate per year of confirmed HIV-1 infections is the number of participants with confirmed HIV-1 infections during the assessment period divided by the number of person-years in the arm. Data are based on participants with confirmed HIV-1 infection. The originally planned primary statistical analysis was removed via amendment when open-label treatment was initiated.
Interventions
- DRUG FTC/TDF
- DRUG Placebo to FTC/TDF
- DRUG Islatravir
- DRUG Placebo to ISL
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 730 participants |
| Start Date | 2021-02-24 |
| Est. Completion | 2024-06-11 |
| Phase | Phase 3 |
Why NCT04644029 stopped before completion
NCT04644029 is an interventional study that assigns participants to a tested intervention. The registered 730 participants enrollment target is mid-sized for trials with a published cap, roughly in line with the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target.
The record links to 0 conditions, and to 4 interventions - of which FTC/TDF is the first listed.
NCT04644029 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04644029 about?
NCT04644029 is a clinical study titled "Oral ISL QM as PrEP in Cisgender Women at High Risk for HIV-1 Infection (MK-8591-022)". This study will evaluate whether oral islatravir (ISL) is effective in preventing Human Immunodeficiency Virus Type 1 (HIV-1) infection in women at high-risk for HIV-1 infection. The study will compare oral ISL taken once a month with standard-of-care medication for prevention of HIV-1 infection, em...
What is the current status of trial NCT04644029?
This trial is currently terminated. It is a Phase 3 study. The enrollment target is 730 participants. The study started on 2021-02-24. Estimated completion is 2024-06-11.
What interventions are being tested in trial NCT04644029?
The interventions under investigation include: FTC/TDF (DRUG), Placebo to FTC/TDF (DRUG), Islatravir (DRUG), Placebo to ISL (DRUG).
Who is sponsoring clinical trial NCT04644029?
This trial is sponsored by Merck Sharp & Dohme, which has 558 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04644029's enrollment target sits among peer trials
730 489th of 2000 higher than 1,512 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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