Participants will be randomized to receive either the combined regimen with T- and B-cell immunogens (CSSMS) or placebo (PPPPP) in a double-blinded fashion at a ratio of 2:1. Safety and immunogenicity of the combined T- and B-cell regimen will be measured up to week 30 (2 weeks after last ConM SOSIP.v7/placebo administration). At week 30, all participants will undergo an ATI of 24 weeks of duration. At visit week 54 (End-of-ATI visit), or before according to pre-specified criteria, ART will be resumed. Efficacy endpoints will be measured at 12 and 24 weeks of ATI (study visits week 42 and 54). After ART resumption, participants will be followed during an additional safety period of 12 weeks (study visit week 66, End-of-Study visit). Treatment allocation will remain blinded until week 54 (End-of-ATI visit).
BCN03 is a Single-site, randomized, double-blind, placebo-controlled, phase I study to evaluate the safety, tolerability, immunogenicity, and efficacy of a vaccine regimen that includes a sequence of the T- and B-cell immunogens ChAdOx1.HTI and MVA.HTI and ConM SOSIP.v7 gp140 adjuvanted with MPLA liposomes in 30 virologically-suppressed ART-treated HIV-1 positive individuals.