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)

Phase 3 Terminated 494 enrolled Merck Sharp & Dohme LLC

RandomizedParallel-groupDouble-blindPrevention

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.

Timeline

Start: 2021-03-15
Primary completion: 2023-08-04
Completion: 2023-08-04

Publications

Results Landovitz RJ, Pinedo Y, Hinestrosa F, Crofoot GE, Brinson C, Buchbinder S, Molina JM, Gravett RM, Brock JB, Ramgopal MN, Rosengren AL, Ofotokun I, Valdez Madruga J, Liegeon G, Panchia R, Supparatpinyo K, Avihingsanon A, Creticos C, Swaminathan S, Doblecki-Lewis S, Rodriguez J, Siegel M, Oka S, Puthanakit T, Grinsztejn B, Sanders EJ, Lama JR, Lombaard J, Ndlovu N, Hwang P, Du J, Jackson B, Homony B, Evans B, Sklar P, Robertson MN, Plank RM. Safety and Tolerability of Oral Islatravir Once Monthly as Pre-Exposure Prophylaxis in Cisgender Men and Transgender Women Who Have an Elevated Likelihood of HIV-1 Exposure: Results From the IMPOWER-24 Randomized Phase 3 Study. Clin Infect Dis. 2026 Mar 14:ciag171. doi: 10.1093/cid/ciag171. Online ahead of print.

Drugs

Evaluation	Drug	Modality	Dose	Route
Comparator	FTC/TAF	Unknown	25 mg	Oral
Comparator	FTC/TAF	Unknown	200 mg	Oral
Comparator	FTC/TDF	Unknown	200 mg	Oral
Comparator	FTC/TDF	Unknown	245 mg	Oral
Subject	Islatravir	Other / unclassified	60 mg	Oral

Indications

No indication recorded.