zaltenibart

Zaltenibart (OMS906) is an investigational human monoclonal antibody developed by Omeros. It targets mannan-binding lectin-associated serine protease-3 (MASP-3), the key and most proximal activator of the alternative pathway of the complement system. By inhibiting MASP-3, zaltenibart blocks the conversion of pro-complement factor D to mature complement factor D, thereby suppressing activation of the alternative pathway while leaving intact the lytic arm of the classical pathway—important for infection defense. This mechanism distinguishes it from C5 and C3 inhibitors, which can increase infection risk by more broadly suppressing complement activity. Zaltenibart is being developed primarily for paroxysmal nocturnal hemoglobinuria (PNH) and complement 3 glomerulopathy (C3G), with additional potential in diseases such as idiopathic immune complex-mediated glomerulonephritis (ICGN), hemolytic uremic syndrome (HUS), traumatic brain injury, arthritis, geographic atrophy ("dry" macular degeneration), ischemia-reperfusion injury, transplant-related complications, and other immune-related disorders[1][4][5][6].

Other names

Humanized immunoglobulin G4 monoclonal antibody directed against mannan-binding lectin-associated serine protease-3