Definition

A fusion protein composed of an engineered immunoglobulin G4 (IgG4) monoclonal antibody directed against terminal complement protein C5 fused to the complement factor H 1-5 domain (FH1-5), with potential anti-inflammatory and immunomodulatory activities. Upon administration of a vensobafusp alfa, the anti-C5 antibody moiety targets and binds to terminal complement protein C5, thereby blocking the terminal complement pathway of complement activation. The FH1-5 moiety inhibits complement C3b deposition, thereby blocking the alternative pathway of complement activation. This inhibits complement-mediated inflammation and cell lysis. Excessive complement activation plays a key role in various inflammatory and autoimmune diseases, and leads to tissue destruction.