A Multicenter Clinical Study of Monoclonal Antibody-Purified Coagulation Factor IX Concentrate (GA-1013) in Treatment of Hemophilia B

Abstract

In order to reduce risk factors in the treatment of hemophilia B with prothrombin complex concentrates, a new coagulation factor IX concentrate (GA-1013) was developed by Green Cross Corporation, Osaka, Japan. This product is prepared by immunoaffinity chromatography using a monoclonal antibody (3A6) and virally inactivated by solvent/detergent treatment. GA-1013 has a specific activity of 173 factor IX units/mg of protein, representing a 13, 700 fold purification from cryosupernatant.
A multicenter clinical study was conducted in 24 previously treated and 1 previously untreated hemophilia B patients with no inhibitor to evaluate the safety and efficacy of GA-1013. We determined the half life and in vivo recovery of this FIX concentrate.
The mean age of the patients was 29.0 years with a range of 9 months 62 years. The mean T1/2 value (n=22) was 20.3±8.93hr and the mean in vivo recovery rate was 69.0±20.12% calculated from the labelled FIX: C content (47.6±14.46% calculated from the actual FIX: C content).
A total of one hundred and seventy-six bleeding episodes were assessed during the 6 months treatment, chiefly on a demand basis. Hemostatic effectiveness was confirmed with an efficacy rate of 93.7% (165/176). No adverse reactions attributed to GA-1013 were obserbed in any infusion. Neither FIX inhibitors nor antibodies to mouse or goat protein were detected. No significant changes attributed to GA-1013 were seen in vital signs or in laboratory findings including CBC, blood chemistries, virological parameters and immunological data (CD4 and CD8 counts, lymphocyte blastogenesis index and serum immunoglobulins at 1, 3 and 6 months).
These results suggest that monoclonal antibody-purified coagulation FIX concentrate (GA-1013) is safe and efficacious as replacement therapy for hemophilia B.