Used in the treatment of paroxysmal nocturnal hemoglobinuria (PNH), a rare blood disorder characterized by the destruction of red blood cells. It works by binding to complement protein C5, preventing its cleavage into active components C5a and C5b, thereby inhibiting the formation of the membrane attack complex (MAC). This action reduces intravascular hemolysis and improves hemoglobin levels, decreasing the need for blood transfusions. Designed for subcutaneous administration, it offers a convenient dosing option with potential for self-administration. Its high target specificity and long half-life support less frequent dosing compared to other complement inhibitors. Also under investigation for other complement-mediated diseases.