CH505M5 N197D mRNA-gp160

CH505M5 N197D mRNA-gp160 is an investigational prophylactic HIV vaccine candidate designed as a messenger RNA (mRNA) vaccine. It encodes a modified HIV-1 envelope glycoprotein (gp160) based on the CH505 strain, incorporating the M5 and N197D mutations to optimize immunogenicity. The vaccine is formulated using lipid nanoparticles (LNPs) for delivery. Its primary mechanism is to stimulate the immune system—specifically, to expand B cell precursors capable of developing into broadly neutralizing antibody (bnAb)-producing cells against HIV. The approach aims to prime and guide B cell maturation toward lineages such as CH235, which are associated with potent bnAb responses in natural infection. This candidate is being evaluated in first-in-human phase 1 clinical trials for safety and immunogenicity in healthy adults without HIV[1][2][3][4][5].