This is a two part study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of MK-1972 in participants with HIV-1 infections. In Part 1, participants will be randomized to receive MK-1972 (at one of 5 different dose levels given once or twice per day) or placebo. Part II will begin after the results of Part I are known; participants will be randomized to receive MK-1972 (only one dose level, twice per day) or placebo. The primary hypotheses are that MK-1972 at the studied doses is safe and well tolerated in HIV-1 infected males; and that MK-1972 has superior antiretroviral activity compared to placebo.

Inclusion Criteria

• Stable baseline health.
• Appropriate use of contraception; condom protection with pregnant partners.
• Documented HIV-1 positive
• Anti-retroviral therapy (ART)-naïve, defined as having never received any antiretroviral agent or ≤30 consecutive days of an investigational antiretroviral agent, excluding an integrase inhibitor, or ≤60 consecutive days of combination ART excluding an integrase inhibitor.
• No investigational agent or licensed ART within 30 days of study drug administration.
• Diagnosis of HIV-1-infection ≥ 3 months prior to screening.

Exclusion Criteria

• History of stroke, chronic seizures, or major neurological disorder.
• History of clinically significant endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological (outside of HIV-1 infection), renal, respiratory, or genitourinary abnormalities or diseases.
• History of clinically significant neoplastic disease.
• Use of any immune therapy agents or immunosuppressive therapy within 1 month prior to treatment in this study.
• Requirement for chronic daily prescription medications.
• Current (active) diagnosis of acute hepatitis due to any cause.
• History of chronic Hepatitis C unless there has been documented cure and/or participant with a positive serologic test for Hepatitis C virus (HCV) has a negative HCV viral load.
• Positive Hepatitis B surface antigen.
• Refusal to stop using any medication, including prescription and non-prescription drugs or herbal remedies (such as St. John's Wort [Hypericum perforatum]) beginning approximately 2 weeks (or 5 half-lives) prior to administration of the initial dose of study drug, throughout the study (including washout intervals), until the post-study visit.
• Consumption of excessive amounts of alcohol, defined as greater than 3 glasses of alcoholic beverages (1 glass is approximately equivalent to: beer [284 mL/10 ounces], wine [125 mL/4 ounces], or distilled spirits [25 mL/1 ounce]) per day.
• Consumption of excessive amounts, defined as greater than 6 servings (1 serving is approximately equivalent to 120 mg of caffeine) of coffee, tea, cola, or other caffeinated beverages per day.
• Smoker of more than 10 cigarettes/day unwilling to restrict smoking to ≤10 cigarettes per day.
• Major surgery, donation or loss of 1 unit of blood (approximately 500 mL) or participation in another investigational study within 4 weeks prior to screening.
• History of significant multiple and/or severe allergies (including latex allergy), or an anaphylactic reaction or significant intolerability to prescription or non-prescription drugs or food.
• Current regular user of any illicit drugs or has a history of drug (including alcohol) abuse within approximately 1 year. Participants with a positive cannabis test with no evidence of drug-dependency may be enrolled at the discretion of the investigator.
• History of hepatic or gallbladder disease or history of clinically significant abnormalities in liver function tests, or history of Gilbert's Syndrome, or history of elevated unconjugated bilirubin.

https://www.merck.com/clinical-trials/pdf/ProcedureAccessClinicalTrialData.pdf