Feasibility and Successful Enrollment in a Proof-of-Concept HIV Prevention Trial of VRC01, a Broadly Neutralizing HIV-1 Monoclonal Antibody.

Abstract

BACKGROUND\nThe Antibody Mediated Prevention (AMP) trials (HVTN 704/HPTN 085 & HVTN 703/HPTN 081) are the first efficacy trials to evaluate whether VRC01, a broadly neutralizing monoclonal antibody (mAb) targeting the CD4 binding site of the HIV envelope protein, prevents sexual transmission of HIV-1. HVTN 704/HPTN 085 enrolled 2,701 cisgender men and transgender (TG) individuals who have sex with men at 26 sites in Brazil, Peru, Switzerland and the United States.\n\n\nMETHODS\nParticipants were recruited and retained through early, extensive community engagement. Eligible participants were randomized 1:1:1 to 10 mg/kg or 30 mg/kg of VRC01 or saline placebo. Visits occurred monthly, with intravenous (IV) infusions every 8 weeks over 2 years, for a total of ten infusions. Participants were followed for 104 weeks after first infusion.\n\n\nRESULTS\nThe median HVTN 704/HPTN 085 participant age was 28; 99% were assigned male sex; 90% identified as cisgender male, 5% as TG female and the remaining as other genders. Thirty-two percent were White, 15% Black and 57% Hispanic/Latinx. Twenty-eight percent had a sexually transmitted infection at enrollment. Over 23,000 infusions were administered with no serious IV administration complications. Overall retention and adherence to the study schedule exceeded 90%, and the drop-out rate was below 10% annually (7.3 per 100-person years) through Week 80, the last visit for the primary endpoint.\n\n\nCONCLUSIONS\nHVTN 704/HPTN 085 exceeded accrual and retention expectations. With exceptional safety of IV administration and operational feasibility, it paves the way for future large-scale mAb trials for HIV prevention and/or treatment.