Biogen Idec and Swedish Orphan Biovitrum (Sobi) announced positive results from A-LONG, a global, open-label, multi-center Phase 3 clinical study that evaluated the efficacy, safety and pharmacokinetics of a recombinant Factor VIII Fc fusion protein (rFVIIIFc), in people with hemophilia A.
In the A-LONG study, 165 male patients aged >12 years were enrolled in three treatment arms: individualized prophylaxis, weekly prophylaxis and episodic (on-demand) treatment (Arms 1, 2 and 3, respectively). In a subgroup of patients across treatment arms, rFVIIIFc was evaluated in the perioperative management of patients who required a major surgical procedure during the study. Top-line results showed that rFVIIIFc was effective in the control and prevention of bleeding, routine prophylaxis and perioperative management.
No inhibitors to rFVIIIFc were detected and no cases of anaphylaxis were reported in any patients, all of whom switched from commercially-available Factor VIII products. Overall, 98% of bleeding episodes were controlled by one or two injections of rFVIIIFc. In a subset of patients with extensive pharmacokinetic sampling, the approximate terminal half-life of rFVIIIFc was 19.0 hours vs. 12.4 hours for Advate [antihemophilic factor (recombinant), plasma/albumin-free method; Baxter], consistent with the results obtained in the Phase 1/2a study of rFVIIIFc.
Recombinant FIXFc is a clotting factor developed using proprietary monomeric Fc fusion technology, which makes use of a natural pathway to recycle rFIXFc in circulation and enable it to remain in the body longer.