Alexion Pharmaceuticals, Inc. (NASDAQ: ALXN) today announced that abstracts relating to Soliris (eculizumab) for patients with paroxysmal nocturnal hemoglobinuria (PNH) have been published by the American Society of Hematology (ASH). Each of these abstracts will be presented at the 2006 ASH Annual Meeting in Orlando, Florida, December 9th to 12th by leading investigators in the Soliris (eculizumab) PNH clinical studies. Copies of the abstracts are available and can be viewed on-line through the ASH website: www.hematology.org/meetings/abstracts.cfm. Access to the on-line abstracts may require registration, for which there is no charge.

The following abstracts will be presented in oral sessions:

• "The Terminal Complement Inhibitor Eculizumab Reduces Thrombosis in Patients with Paroxysmal Nocturnal Hemoglobinuria"
  Dr. Peter Hillmen et al.
  Time: Sunday, December 10th at 5:00pm
  Room 315
• "Treatment with the Terminal Complement Inhibitor Eculizumab Improves Anemia in Patients with Paroxysmal Nocturnal Hemoglobinuria: Phase III TRIUMPH Study Results"
  Dr. Jrg Schubert et al.
  Time: Sunday, December 10th at 5:15pm
  Room 315

The following abstracts will be presented in poster sessions:

• "Safety and Efficacy of the Terminal Complement Inhibitor Eculizumab in Patients with Paroxysmal Nocturnal Hemoglobinuria: SHEPHERD Phase III Clinical Study"
  Poster # 99-I
  Dr. Neal S. Young et al.
  Time: Saturday, December 9th at 9:00am
  Hall E-1
• "Blockade of Intravascular Hemolysis in PNH with the Terminal Complement Inhibitor Eculizumab Unmasks Low-Level Hemolysis Potentially Occurring through C3 Opsonization"
  Poster #100-I
  Dr. Anita Hill et
  '"/>