CSL Behring announces results of rIX-FP Phase I study on hemophilia B

CSL Behring today announced the results of a Phase I study evaluating recombinant fusion protein linking coagulation Factor IX with albumin (rIX-FP) in patients with severe hemophilia B.  Results of the study, which were presented during an oral session at the Gesellscaft fur Thrombose- und Hameostasegorschung (GTH) congress in Switzerland, showed that rIX-FP was well tolerated in all patients and lasted longer in the body, due to its prolonged half-life, compared with current Factor IX treatment options.

CSL Behring, in collaboration with its parent company, CSL Limited (ASX:CSL), is developing rIX-FP for the prophylaxis and treatment of bleeding episodes in patients with congenital Factor IX (FIX) deficiency as part of the PROLONG-9FP clinical study program.

"Hemophilia B is a rare and serious bleeding disorder that prevents normal blood clotting and requires frequent infusion of Factor IX concentrates to restore clotting ability," said Elena Santagostino, M.D., Ph.D., Professor in the Medical School of Clinical and Experimental Hematology at the University of Milan/IRCCS Maggiore Hospital. "The results of this study suggest that rIX-FP is a promising investigational agent for improvement of prophylactic and on-demand treatment for patients with hemophilia B."

In this analysis, no serious adverse events (including no hypersensitivity reactions), presence of inhibitors to Factor IX, or antibodies to rIX-FP were reported.  Terminal half-life (a measure of how long the drug lasts in the body) was more than five-times longer in comparison to values associated with current recombinant FIX therapy. Incremental recovery and area under the curve (a measure of total exposure to the drug) were also significantly improved in comparison to values associated with current recombinant FIX therapy. 

"The development of this new recombinant investigational agent further adds to CSL Behring's long heritage of identifying innovative treatments to improve outcomes for those living with rare bleeding disorders," said Dr. Stefan Schulte, Vice President of Research and Development, CSL Behring. "We look forward to further exploring the potential of rIX-FP in patients with hemophilia B."