VRC01LS

VRC01LS is a long-acting, human IgG1 broadly neutralizing monoclonal antibody (bNAb) engineered for extended half-life. It is derived from the original VRC01 antibody and differs by two amino acid substitutions (M428L and N434S) in the Fc region, which enhance binding to the neonatal Fc receptor (FcRn), thereby prolonging its serum persistence. Like VRC01, it targets a conserved region of the CD4 binding site on HIV-1 envelope glycoprotein gp120, blocking viral entry into host cells. The LS modification does not impair effector functions such as antibody-dependent cellular cytotoxicity. Developed primarily for HIV prevention and treatment—including in pediatric populations—VRC01LS has demonstrated safety and tolerability in clinical trials with both intravenous and subcutaneous administration routes. Its extended half-life allows for less frequent dosing compared to unmodified bNAbs[6][7].