Baxter International Inc. announced it has submitted an Investigational New Drug (IND) application for its investigational hemophilia A treatment BAX 855 with the U.S. Food and Drug Administration, following positive results from a Phase I trial. BAX 855 is a full-length longer-acting recombinant factor VIII (rFVIII) that was developed to increase the half-life of ADVATE [Antihemophilic Factor (Recombinant) Plasma/Albumin-Free Method] -- the most widely chosen rFVIII in the world. Baxter expects to start enrollment of adult patients in its Phase II/III study in the first quarter of 2013.

A phase I prospective, open-label trial assessing the safety, tolerability and pharmacokinetics of BAX 855 was conducted in 19 previously treated patients age 18 years or older with severe hemophilia A who completed the trial. The half-life (measuring the duration of activity of the drug in the body) of BAX 855 was approximately 1.5-fold higher compared to ADVATE. A longer half-life was achieved in all patients in the study using BAX 855, no patients developed inhibitors to either base molecule, BAX 855 or PEG, and no patients had allergic reactions.

Eleven adverse events were reported in eight patients across both treatment arms, but none was serious, treatment-related or resulted in withdrawal from the study. Phase II/III multi-center, open-label study called PROLONG-ATE will be initiated in the United States during first quarter of 2013 with more than 100 previously treated adult patients with severe hemophilia A to assess the efficacy, safety and pharmacokinetics of BAX 855 for prophylaxis and on-demand treatment of bleeding.