Study of Lenacapavir and Emtricitabine/Tenofovir Disoproxil Fumarate (F/TDF) for Prevention of HIV in People Who Inject Drugs (HPTN 103)

The goals of this clinical study are to look at how lenacapavir (LEN) passes through the body and to assess the safety of LEN and emtricitabine/tenofovir disoproxil fumarate (F/TDF) for pre-exposure prophylaxis (PrEP) in people who inject drugs (PWID) in the United States (US). The primary objectives of this study are to characterize the pharmacokinetics (PK) of LEN and to evaluate the safety of LEN and F/TDF for PrEP in US PWID.

Key Inclusion Criteria: * Urine drug screen positive for any drug of misuse including, but not limited to, opioids (eg, fentanyl, heroin), stimulants (eg, cocaine, amphetamines), psychoactive drugs (eg, benzodiazepines), or a combination of these drugs. * Evidence of recent injection (eg, track marks). * Self-report of injection paraphernalia sharing in the prior 30 days. * Hepatitis B virus (HBV) surface antigen (HBsAg) negative. * Negative local rapid HIV-1/2 antibody (Ab)/antigen (Ag) test, central HIV-1/2 Ab/Ag, and HIV-1 RNA quantitative nucleic acid amplification testing (NAAT). * Estimated glomerular filtration rate (GFR) at least 60 mL/min at screening according to the Cockcroft-Gault formula for creatinine clearance (CLcr). Key Exclusion Criteria: * Self-reported history of previous positive results on an HIV test. * Any reactive or positive HIV test result at screening or enrollment, even if HIV infection is not confirmed. * Coenrollment in any other interventional research study or other concurrent studies that may interfere with this study (as provided by self-report or other available documentation) without prior approval from the Medical Monitor/Joint Clinical Management Committee while participating in this study. * Past or current participation in HIV vaccine or HIV broadly neutralizing antibody study unless individual provides documentation of receipt of placebo (ie, not active product). * Prior use of long-acting systemic pre-exposure prophylaxis (PrEP) (including cabotegravir (CAB) or islatravir studies). * Acute viral hepatitis A or acute or chronic hepatitis B or C infection. * Have a suspected or known active, serious infection(s) (eg, active tuberculosis, etc). * Evidence of moderate or severe liver fibrosis or a history of or current clinical decompensated liver cirrhosis (eg, ascites, encephalopathy, variceal bleeding). In individuals with active hepatitis C, Fibrosis-4 (FIB-4) score \> 3.25 (formula provided below). Note: Other protocol defined Inclusion/Exclusion criteria may apply.