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)

A Phase 2a, Double-Blind, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of Oral MK-8591 Once-Monthly in Participants at Low- Risk for HIV-1 Infection

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

This study is ongoing for collection of safety follow-up of infants born to mothers participating in the study. The present results are based on the Week 68 interim analysis.

Inclusion Criteria:

• Is in general good health with acceptable laboratory values at screening
• Is confirmed HIV-uninfected based on negative HIV-1/HIV-2 test result before randomization
• Has low risk of HIV infection, within 12 months prior to screening visit or the rescreening visit (if applicable)
• Use contraceptives consistent with local regulations
• Female is not pregnant or breastfeeding, and is not a woman of childbearing potential (WOCBP)
• A WOCBP is using an acceptable contraceptive method, or is abstinent from heterosexual intercourse as their preferred and usual lifestyle; or has a negative pregnancy test.

Exclusion Criteria:

• Has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator

• Has an active diagnosis of hepatitis due to any cause

• Has a history of malignancy ≤5 years prior to signing informed consent except for adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer.

• Is taking or is anticipated to require systemic immunosuppressive therapy, immune modulators, or any prohibited therapies from 30 days prior to Day

  1 through the duration of the study.

• Is currently participating in or has participated in an interventional clinical study with an investigational compound or device within 30 days prior to Day1 through the duration of the study.

• Has previously been randomized in a study and received islatravir (MK-8591).

• Female is expecting to conceive or donate eggs at any time during the study

• Has QTc interval (using Fridericia correction) >450 msec (for males) or >460 msec (for females) or deemed clinically abnormal by the investigator.