Safety, Immunogenicity, Efficacy of Ad26.Mos4.HIV, MVA-BN-HIV and PGT121, PGDM1400, and VRC07-523LS in HIV-1-Infected Adults

The study will enroll 36 adults randomized in a 1:1:1 ratio to 3 groups (vaccines+ bNAbs, vaccine+placebo, placebo+bNAbs), respectively. The study population will include HIV-infected adults who are on suppressive ART for at least 48 weeks prior to screening. The study comprises of a screening period of 10 weeks (Stage 0), a 24-week vaccination and follow-up period (Stage 1), a 4-week bNAb administration period and a 20-week bNAb washout period (Stage 2), and a 24-week monitoring period (Stage 3). An analytical antiretroviral treatment interruption (ATI) to assess rates of sustained virologic suppression will be conducted during Stages 2-3. Participants will record solicited signs and symptoms in a diary on the evening after each study drug administration and then daily for the next 7 days. Further safety evaluations will include monitoring of AEs, physical examinations, vital sign measurements, clinical laboratory tests (including urinalysis, CD4 count and HIV RNA), and for women, also pregnancy testing. Blood samples will be taken at specific clinic visits to assess immune and virologic responses as well as the pharmacokinetics and pharmacodynamics of bNAbs.