Eculizumab prevents intravascular hemolysis in patients with paroxysmal nocturnal hemoglobinuria and unmasks low-level extravascular hemolysis occurring through C3 opsonization

Abstract

These data demonstrate a previously masked mechanism of red cell clearance in paroxysmal nocturnal hemoglobinuria and suggests that blockade of complement at C5 allows C3 fragment accumulation on some paroxysmal nocturnal hemoglobinuria red cells, explaining the residual low-level hemolysis occurring in some eculizumab-treated patients.