CSL Behring rIX-FP granted Orphan Drug Designation to treat hemophilia B

CSL Behring announced today that the company has been granted Orphan Drug Designation by the United States Food and Drug Administration for its novel recombinant fusion protein linking coagulation factor IX with recombinant albumin (rIX-FP). The Orphan Drug Designation is granted for the treatment and prophylaxis of bleeding episodes in patients with congenital factor IX deficiency (hemophilia B). The designation includes routine prophylaxis treatment, control and prevention of bleeding episodes, and prevention and control of bleeding in perioperative settings.

CSL Behring is developing this therapy in collaboration with its parent company CSL Limited (ASX: CSL).

"CSL Behring is pleased to have achieved this important regulatory milestone for our recombinant factor IX," said Val Romberg, Senior Vice President, Research and Development at CSL Behring. "It represents yet another advance that our company is making in the area of recombinant factor development and is extremely encouraging."

CSL Behring has engineered rIX-FP to extend the half-life of Factor IX through genetic fusion with recombinant albumin. Albumin has been chosen as the ideal recombinant genetic fusion partner for coagulation factor proteins due to its long physiological half-life. In addition, albumin has been shown to have a good tolerability profile, low potential for immunogenic reactions and a well-known mechanism of clearance compared to some other technologies. The cleavable linker connecting recombinant factor IX and recombinant albumin has been specifically designed to preserve the native function of the coagulation factor in the fusion protein, while benefiting from recombinant albumin's long physiological half-life.

The FDA's Orphan Drug Designation program provides orphan status to unique drugs and biologics, defined as those intended for the safe and effective treatment or prevention of rare diseases that affect fewer than 200,000 people in the U.S.

SOURCE CSL Behring