ROCKVILLE, MarylandThe FDA has approved Alexion Pharmaceuticals' Soliris (eculizumab), the first product for the treatment of paroxysmal nocturnal hemoglobinuria (PNH), a rare, disabling and life-threatening blood disorder defined by chronic red blood cell destruction (hemolysis). Soliris is classified as an Orphan Drug and is a new molecular entity.
Hemolysis can cause one or more of the following symptoms in patients with PNH: severe anemia, disabling fatigue, recurrent pain, shortness of breath, pulmonary hypertension, intermittent episodes of hemoglobinuria, kidney disease, impaired quality of life, and thromboses. The average age of onset is in the early 30s; estimated median survival is 10 to 15 years from the time of diagnosis.
Patients with PNH are missing a specific protein that normally protects red blood cells from destruction by terminal complement, a component of the immune system. Soliris, the first complement inhibitor approved in the United States for the treatment of any disease, prevents hemolysis by selectively blocking terminal complement.
FDA based its approval on Alexion's randomized, double-blind, placebo-controlled clinical study of 87 PNH patients, known as TRIUMPH, and other clinical studies. Over a 26-week period, half of the participants receiving Soliris in the TRIUMPH study had stabilization of blood hemoglobin levels vs no stabilization among the placebo patients. Soliris-treated patients also required significantly fewer blood transfusions. Serious meningococcal infection was the most important adverse reaction. The product labeling requires meningococcal vaccination prior to receiving Soliris.