Study to Evaluate the Safety and Efficacy of Emtricitabine and Tenofovir Alafenamide (F/TAF) Fixed-Dose Combination Once Daily for Pre-Exposure Prophylaxis in Men and Transgender Women Who Have Sex With Men and Are At Risk of HIV-1 Infection

Key Inclusion Criteria: * Must be at high risk of sexual acquisition of HIV * HIV-1 negative status * MSM and TGW (male at birth) who have at least one of the following: * condomless anal intercourse with at least two unique male partners in the past 12 weeks (partners must be either HIV-infected or of unknown HIV status) * documented history of syphilis in the past 24 weeks * documented history of rectal gonorrhea or chlamydia in the past 24 weeks * Adequate renal function: estimated glomerular filtration rate ≥ 60 mL/min according to the Cockcroft-Gault formula * Adequate liver and hematologic function: * Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × upper limit of normal (ULN) and total bilirubin ≤ 1.5 mg/dL, or normal direct bilirubin * Absolute neutrophil count ≥ 1000/mm\^3; platelets ≥ 75,000/mm\^3; hemoglobin ≥ 10 g/dL Key Exclusion Criteria * Grade 3 or Grade 4 proteinuria or glycosuria that is unexplained or not clinically manageable. NOTE: Other protocol defined Inclusion/ Exclusion criteria may apply.