European Commission Approves Hemophilia B Therapy Alprolix Extended Protection

The biotech companies Swedish Orphan Biovitrum AB (Sobi) and Biogen have announced that the European Commission (EC) has approved their extended half-life therapy Alprolix (rFIXFc) for hemophilia B in all 28 European Union (EU) countries. In addition, the EC maintained the drug’s orphan designation.

The World Federation of Hemophilia (WFH) estimated in 2014 that nearly 28,000 people globally were currently living with hemophilia B. Hemophilia B is caused by having significantly reduced or no factor IX activity, which is needed for normal blood clotting. Hemophilia patients report experiencing bleeding episodes in joints and muscles that cause pain, reduced mobility, and irreversible joint damage. Infusions of factor IX temporarily replace clotting factors necessary to resolve bleeding and, if used prophylactically, can prevent new bleeding episodes. Alprolix is now the only recombinant factor IX Fc Fusion protein therapy for hemophilia B to provide Europeans long-term protection against bleeding episodes with fewer prophylactic injections needed.

The European Commission’s approval of Alprolix was based on results from two global Phase 3 clinical trials: the pivotal B-LONG study, for previously treated adults and teens; and the Kids B-LONG study, for previously treated children under 12 years old. Both trials evaluated Alprolix’s efficacy, safety, and pharmacokinetics profile for hemophilia B.

Adverse reactions occurred with an incidence of greater than 0.5 percent and included nasopharyngitis (common cold), influenza, arthralgia (joint pain), upper respiratory tract infection, headaches, and hypertension. Most of these reactions were analyzed and declared not related, or not likely related to the drug being studied.

“With the approval of Alprolix, people with hemophilia B in Europe now have the potential to experience prolonged protection from bleeds with fewer injections,” said Krassimir Mitchev, M.D., Ph.D., SOBI’s vice president and Medical Therapeutic Area head of hemophilia, in a press release. “We are working to make Alprolix available in Europe as quickly as possible. Along with Biogen, we’re excited to continue offering innovative therapies to people with hemophilia around the world.”

Alprolix is indicated for on-demand and prophylaxis treatment of hemophilia B patients of all ages. It can be given with an initial dose every week or every 10 days, with the ability to adjust the dosing interval based on patients’ response. The recombinant clotting factor therapy was developed for hemophilia B by fusing factor IX to the Fc portion of immunoglubin G subclass 1 (igG1), a protein commonly found in our bodies. This technology allows Alprolix to use natural pathways to prolong the time the therapy remains active.

“Alprolix has become a meaningful treatment advance for people living with hemophilia B in countries where it is approved and is backed by robust clinical data and the longest real-world experience of any prolonged circulation factor IX therapy to date,” said Biogen Senior Vice President of Drug Innovation Units, Gilmore O’Neill, M.D. “We’re proud to bring the European hemophilia community one of the first treatment advances in nearly 20 years, and believe the availability of extended half-life therapies in Europe will change the way that many approach treatment.”