# Oral Islatravir (MK-8591) Once-Monthly as Preexposure Prophylaxis (PrEP) in Men and Transgender Women Who Are at High Risk for HIV-1 Infection (MK-8591-024)

> **NCT04652700** · PHASE3 · TERMINATED · sponsor: **Merck Sharp & Dohme LLC** · enrollment: 494 (actual)

## Conditions studied

- HIV Preexposure Prophylaxis

## Interventions

- **DRUG:** ISL
- **DRUG:** FTC/TDF
- **DRUG:** FTC/TAF
- **DRUG:** Placebo to ISL
- **DRUG:** Placebo to FTC/TDF
- **DRUG:** Placebo to FTC/TAF

## Key facts

- **NCT ID:** NCT04652700
- **Lead sponsor:** Merck Sharp & Dohme LLC
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** TERMINATED
- **Start date:** 2021-03-15
- **Primary completion:** 2023-08-04
- **Final completion:** 2023-08-04
- **Target enrollment:** 494 (ACTUAL)
- **Why stopped:** Voluntarily terminated due to benefit/risk assessment.
- **Last updated:** 2026-05-05


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04652700

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04652700, "Oral Islatravir (MK-8591) Once-Monthly as Preexposure Prophylaxis (PrEP) in Men and Transgender Women Who Are at High Risk for HIV-1 Infection (MK-8591-024)". Retrieved via AI Analytics 2026-06-24 from https://api.ai-analytics.org/clinical/NCT04652700. Licensed CC0.

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