Positive results for Alprolix in Kids B-LONG study treatment for haemophilia B- SOBI+ Biogen

Biogen Idec and Swedish Orphan Biovitrum AB announced positive top-line results of the Kids B-LONG Phase III clinical study that evaluated the safety, efficacy and pharmacokinetics of Alprolix [Coagulation Factor IX (Recombinant), Fc Fusion Protein] in children under age 12 with severe haemophilia B. Alprolix was generally well tolerated and no inhibitors (neutralising antibodies that may interfere with the activity of the therapy) were detected during the study. In this study, once-weekly prophylactic dosing with Alprolix resulted in low bleeding rates. Alprolix is the only approved hemophilia B therapy with prolonged circulation in the body.The successful completion of Kids B-LONG supports applications for paediatric indications in several geographies and is an important step in seeking marketing authorisation for Alprolix in Europe. The European Medicines Agency requires the inclusion of paediatric study data in the initial marketing application for a new haemophilia therapy. Interim results of the Kids B-LONG study helped support the U.S. approval of Alprolix for use in children.

In the study, children treated prophylactically with Alprolix had an overall median ABR (annualised bleeding rate) of 1.97. The median ABR for spontaneous joint bleeds was zero. Approximately 33 percent of participants in the study experienced zero bleeding episodes. Overall, 91.7 percent of bleeding episodes were controlled by one or two injections of Alprolix. The terminal half-life of Alprolix in the study was 66.5 hours for children under six and 70.3 hours for children six to less than 12 years of age. Additional analyses of the Kids B-LONG study are ongoing, and detailed results will be presented at a future scientific meeting. No inhibitors to Alprolix were detected during the study.

Comment:Treatment of haemophilia B requires frequent infusions of factor IX (FIX) to prophylax against bleeding episodes. Currently, treatment requires intravenous injections up to three times a week, which makes the prospect of a longer-lasting Factor IX therapy very exciting. Haemophilia B, a rare, inherited clotting disorder, occurs in about one in 25,000 male births annually.