Trial to Evaluate the Safety and Immunogenicity of Priming Regimens of 426c.Mod.Core-C4b and Optional Boost Regimen With HIV Trimer BG505 SOSIP.GT1.1 gp140, Both Adjuvanted With 3M-052-AF + Alum in Healthy, Adult Participants Without HIV

Description

The clinical study is designed to evaluate the ability of two priming vaccine regimens to activate and induce the maturation of cross-reactive CD4 binding site (CD4-bs) antibodies, including VRC01-class antibodies. VRC01- class antibodies are highly desirable to elicit via vaccination because they have broad cover all clades of HIV and passive administration of VRC01 monoclonal antibodies has been demonstrated to prevent acquisition of susceptible HIV strains in clinical trials. The study will assess whether B cells expressing VRC01-like B cell receptors proliferate following immunization with a ‘germline-targeting’ recombinant Env immunogen. The study will also test whether an immunization strategy based upon fractionated dose delivery of the immunogen may improve the maturation of VRC01-class B cells when compared to traditional bolus dosing. In addition, the study will test whether alterations in the dose of the subsequent boost immunizations affects VRC01-class B cell activation and the rate of antibody affinity maturation.

The primary hypothesis of the optional boost regimen is that BG505 SOSIP.GT1.1 gp140 adjuvated with 3M-052-AF + Alum is safe and well-tolerated and will further mature B-cell lineages elicited by 426c.Mod.Core-C4b priming regimens.