A Phase 1 Study to Evaluate the Safety and Immunogenicity of eOD-GT8 60mer mRNA Vaccine (mRNA-1644) and Core-g28v2 60mer mRNA Vaccine (mRNA-1644v2-Core)

A Phase 1, Randomized, First-in-human, Open-label Study to Evaluate the Safety and Immunogenicity of eOD-GT8 60mer mRNA Vaccine (mRNA-1644) and Core-g28v2 60mer mRNA Vaccine (mRNA-1644v2-Core) in HIV-1 Uninfected Adults in Good General Health. The hypothesis is that sequential vaccination by a germline-targeting prime followed by directional boost immunogens can induce specific classes of B-cell responses and guide their early maturation toward broadly neutralizing antibody (bnAb) development through an mRNA platform. Fifty-six participants. Adults 18 to 50 years of age who meet all protocol inclusion criteria, who do not meet any protocol exclusion criteria, who understand the study (as demonstrated by the Assessment of \[Informed Consent\] Understanding \[AOU\]), and who can provide written informed consent. Randomization allocation is 16:16:16:8 for Groups 1-4 respectively. There is no blinding in this study. Site and study staff will not be blinded to the IP.