ALEXION ANNOUNCES DATA ON DRUG FOR PNH

Eculizumab, a novel monoclonal antibody drug developed by Alexion Pharmaceuticals, appeared to be safe and well-tolerated and provided clinically and statistically significant improvements in intravascular hemolysis, anemia, fatigue and quality of life in patients with paroxysmal nocturnal hemoglobinuria (PNH) during the 52 weeks of treatment in the Phase III SHEPHERD clinical trial. These results were presented at meeting of the American Society of Hematology.

Patients with PNH lack naturally occurring complement inhibitors on the surface of their red blood cells that normally prevent red blood cell destruction. PNH patients are at increased risk of forming life-threatening blood clots, or thromboses. Eculizumab, a long-acting C5 complement inhibitor, is a humanized monoclonal antibody drug designed to selectively block terminal complement activation, thereby preventing destruction of red blood cells by complement in patients with PNH.

SHEPHERD was an open-label Phase III study in which patients received eculizumab for 52 weeks. The prespecified primary endpoints of the trial were safety and a reduction in intravascular hemolysis as measured by the surrogate endpoint lactate dehydrogenase. Prespecified secondary endpoints included fatigue and intravascular hemolysis; other endpoints assessed included patient reported outcomes and measures of anemia including transfusion requirements. During the study, eculizumab was found to be well tolerated with an adverse event profile similar to that of placebo patients in the Phase III TRIUMPH study. Further, no serious adverse events were deemed probably or definitely related to treatment.

Alexion also announced the initiation of an expanded access program for eculizumab in the United States for patients with PNH, in accordance with a treatment protocol authorized by the FDA.