Stockholm, Sweden and Waltham, MA - May 27, 2008. Biovitrum AB (STO: BVT) and Syntonix Pharmaceuticals, Inc., a subsidiary of Biogen/Idec (NASDAQ: BIIB) today announced the initiation of a phase I/IIa open-label, dose escalation study of a long-acting, recombinant Factor IXFc (FIXFc) protein in patients with hemophilia B. The study is ongoing at clinics in the United States and will assess the safety, tolerability and pharmacokinetics of Factor IXFc in this patient population.