Mos3.3

Mos3.3 is an experimental recombinant protein immunogen designed for use in HIV-1 vaccine development. It is one of three mosaic HIV-1 envelope (Env) gp140 trimers (alongside Mos3.1 and Mos3.2) developed by the European AIDS Vaccine Initiative 2020 (EAVI2020) consortium to address the global genetic diversity of HIV-1. The mosaic sequences are bioinformatically optimized to maximize the coverage of potential T-cell and B-cell epitopes across multiple HIV-1 subtypes. Mos3.3 is engineered as a soluble gp140 trimer that mimics the native viral envelope spike in a stabilized, native-like conformation. In clinical research, such as the experimental medicine trial NCT03816137, Mos3.3 is used as part of a trivalent mosaic boost regimen to expand the breadth of the immune response, aiming to prime germline B cells and drive the maturation of broadly neutralizing antibodies (bNAbs) against conserved vulnerability sites on the Env protein.

Other names

HIV-1 mosaic gp140 trimer 3.3HIV1 mosaic gp140 trimer 3.3HIV 1 mosaic gp140 trimer 3.3