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)

A Phase 3, Randomized, Active-Controlled, Double-Blind Clinical Study to Evaluate the Efficacy and Safety of Oral Islatravir Once-Monthly as Preexposure Prophylaxis in Cisgender Men and Transgender Women Who Have Sex With Men, and Are at High Risk for HIV-1 Infection

• Status: Terminated
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 494 (actual)
• Sponsor: Merck Sharp & Dohme LLC · Industry
• Sex: Male
• Age: 16 Years
• Healthy volunteers: Accepted

Summary

The main purpose of the study is to evaluate the safety and tolerability of oral Islatravir (ISL) once monthly (QM) as Preexposure Prophylaxis (PrEP) in cisgender men who have sex with men (MSM) and transgender women (TGW) who have sex with men and who are at high risk of HIV-1 infection with 48 or 96 weeks of treatment and a minimum follow-up of 42 days.

Detailed description

Based on laboratory findings of decreased lymphocyte and CD4+ T-cell counts across the islatravir program, dosing of blinded study intervention was halted on 13-Dec-2021. Blinded assessments conducted prior to then are designated as Study Part 1. During Study Part 2, participants from Part 1 were switched to PrEP therapy with emtricitabine/tenofovir disoproxil (FTC/TDF) or emtricitabine/tenofovir alafenamide (FTC/TAF) while continuing in the study, but participants, investigators, and Sponsor personnel remained blinded to the Part 1 treatment. In Part 3, participants, investigators, and all Sponsor personnel are unblinded to participant's original randomized intervention group, and participants may continue to receive unblinded FTC/TDF or FTC/TAF.

Conditions

• HIV Preexposure Prophylaxis

Interventions

Type	Name	Description
DRUG	ISL	ISL 60 mg tablet, QM, orally for up to 24 months
DRUG	FTC/TDF	Participants receive 200/245 mg of FTC/TDF combination tablet, QD, orally for up to 24 months
DRUG	FTC/TAF	Participants receive 200/25 mg of FTC/TAF combination tablet, QD, orally for up to 24 months
DRUG	Placebo to ISL	Placebo ISL 0 mg tablets QM, orally for up to 24 months.
DRUG	Placebo to FTC/TDF	Placebo FTC/TDF 0 mg tablets QD, orally for up to 24 months
DRUG	Placebo to FTC/TAF	Placebo FTC/TAF 0 mg tablets QD, orally for up to 24 months

Timeline

• Start date: 2021-03-15
• Primary completion: 2023-08-04
• Completion: 2023-08-04
• First posted: 2020-12-03
• Last updated: 2025-01-13
• Results posted: 2024-12-11

Locations

25 sites across 7 countries: United States, Brazil, France, Japan, Peru, South Africa, Thailand

Regulatory

• FDA-regulated drug study