( - Data presented at 12th Congress of Eu...)Studies Show Efficacy and Safety of Alexion's Soliris in Broad,Population of PNH Patients,Health

CHESHIRE, Conn., June 11, 2007 /PRNewswire-FirstCall/ -- Alexion Pharmaceuticals, Inc. today announced results from three analyses of Phase III studies examining Soliris(TM) (eculizumab) for the treatment of paroxysmal nocturnal hemoglobinuria (PNH) at the 12th Congress of European Hematology, organized by The European Hematology Association (EHA) in Vienna. These presentations included:

"The Terminal Complement Inhibitor Eculizumab Reduces Thrombosis in Patients with Paroxysmal Nocturnal Hemoglobinuria (PNH)," presented by Dr. Peter Hillmen of the General Infirmary at the University of Leeds, Leeds, UK.(1) (Abstract No. 0380)

"Safety and Efficacy of the Terminal Complement Inhibitor Eculizumab in Patients with Paroxysmal Nocturnal Hemoglobinuria: SHEPHERD Phase III Clinical Study Results," presented by Dr. Hubert Schrezenmeier of the University Hospital Ulm in Ulm, Germany.(2) (Abstract No. 0378)

"The Clinical Benefit of Eculizumab Is Demonstrable in all Subpopulations of Patients with Paroxysmal Nocturnal Hemoglobinuria (PNH) with Hemolysis," presented by Dr. Petra Muus of Radboud University, Nijmegen, Netherlands.(3) (Abstract No. 0379) Subpopulations were diverse and included patients with poor bone marrow function, smaller PNH clone sizes, low levels of hemolysis, less anemia, minimal pre-treatment transfusion requirements and those receiving steroids or erythropoietin.

Dr. Muus noted, "In published clinical trials, Soliris significantly reduced hemolysis in all PNH patients, which led to an improvement in anemia, patient functioning and quality of life, and fewer thrombotic events. Research presented this week at the Congress in Vienna described the impact of Soliris on multiple subgroups of PNH patients and showed that the effect of Soliris was maintained across all subpopulations including in those patients who had as
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