CSL Behring has received FDA orphan drug designation for its recombinant fusion protein linking coagulation factor IX with recombinant albumin (rIX-FP).
The designation was granted for the treatment and prophylaxis of bleeding episodes in patients with congenital factor IX deficiency (hemophilia B).
CSL Behring research and development senior vice president Val Romberg said the designation represents an advance that the company is making in the area of recombinant factor development.
The designation takes account of routine prophylaxis treatment, control and prevention of bleeding episodes, and prevention and control of bleeding in perioperative settings.
The company has engineered rIX-FP to extend the half-life of Factor IX through genetic fusion with recombinant albumin.
Because of its long physiological half-life, good tolerability profile, low potential for immunogenic reactions and a well known mechanism of clearance compared to some other technologies, albumin was selected as the recombinant genetic fusion partner for coagulation factor proteins.
The cleavable linker, which connects recombinant factor IX and recombinant albumin, was designed to preserve the native function of the coagulation factor in the fusion protein.