VIB9600

VIB9600 is a humanized, effector-deficient monoclonal antibody that specifically targets and antagonizes the Fc gamma receptor IIA (FcγRIIA, also known as CD32A). Developed originally by MedImmune and later by Viela Bio (now part of Horizon Therapeutics), this antibody blocks IgG immune complex-mediated cellular activation. Its mechanism involves both blocking ligand engagement at FcγRIIA and internalizing the receptor from the cell surface, thereby suppressing proinflammatory responses driven by immune complexes. Preclinical studies demonstrated its ability to inhibit type I interferon production in plasmacytoid dendritic cells (relevant to systemic lupus erythematosus), reactive oxygen species generation in neutrophils (relevant to ANCA-associated vasculitis), and cytokine production such as TNF-α and IL-6 (relevant to rheumatoid arthritis). In animal models, VIB9600 reduced disease activity in conditions like thrombocytopenia, nephritis, and arthritis. The drug has shown favorable pharmacokinetics and safety profiles in non-human primate studies[1][2][3][5].

Other names

FcγRIIA antibody - AstraZeneca