Safety and Pharmacokinetics of Oral Islatravir (MK-8591) Once Monthly in Participants at Low Risk of Human Immunodeficiency Virus 1 (HIV-1) Infection (MK-8591-016)

Summary

This study will evaluate the safety, tolerability and pharmacokinetics (PK) of 6 once-monthly doses of oral islatravir (60 mg and 120 mg) compared with placebo in adults at low risk of HIV-1 infection

Timeline

Start

2019-09-19

Primary completion

2022-03-18

Completion

2022-11-24

Publications

• Results Hillier SL, Bekker LG, Riddler SA, Hendrix CW, Badal-Faesen S, Macdonald P, Nair G, Lombaard J, Caraco Y, Peer A, Patel M, Vargo R, Homony B, Nedrow K, Evans B, Wickremasingha P, Zhou YP, Teal V, Hwang P, McMullan C, Kaufman KD, Robertson MN, Plank RM. Safety, Tolerability, and Pharmacokinetics of Once-Monthly Oral Islatravir: A Phase 2a Study in Participants at Low Risk for Acquiring Human Immunodeficiency Virus Type 1. J Infect Dis. 2025 Nov 14;232(5):1050-1060. doi: 10.1093/infdis/jiaf222.
• Hendrix CW, Hillier SL, Bekker LG, Badal-Faesen S, Riddler SA, Marzinke MA, Fuchs EJ, Macdonald P, Edick S, Weld ED, Chavez-Eng CM, Evans B, Zang X, Vargo R, Homony B, Nedrow K, Plank RM, Robertson MN, Wickremasingha P, Patel M. Islatravir distribution in plasma, peripheral blood mononuclear cells, and mucosal tissues after monthly oral dosing. AIDS. 2026 Aug 1;40(8):1087-1096. doi: 10.1097/QAD.0000000000004477. Epub 2026 Mar 25.
• Pham M, Wickremasingha P, Vargo R, Patel M, Nedrow K, Homony B, Robertson MN, Plank RM. Brief Report: Exploratory Substudy of a Phase 2 Trial to Evaluate the Pharmacokinetic Effect of Once-Monthly Islatravir on Long-Acting Reversible Contraceptives. J Acquir Immune Defic Syndr. 2025 Aug 1;99(4):374-378. doi: 10.1097/QAI.0000000000003678.
• Devanathan AS, Cottrell ML. Pharmacology of HIV Cure: Site of Action. Clin Pharmacol Ther. 2021 Apr;109(4):841-855. doi: 10.1002/cpt.2187. Epub 2021 Mar 5.

Drugs

Indications