Alexion Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted orphan drug designation (ODD) to ALXN1210, a highly innovative, longer-acting anti-C5 antibody that inhibits terminal complement, which is being evaluated for the treatment of patients with paroxysmal nocturnal hemoglobinuria (PNH). PNH is a debilitating, ultra-rare, life-threatening blood disorder in which uncontrolled activation of complement, a component of the immune system, results in hemolysis (destruction of a patient’s red blood cells).