BETHESDA, MD 27 June 2013—FDA on June 26 approved a recombinant coagulation factor IX product for the routine prophylaxis of bleeding episodes in adults with hemophilia B.
Known by the brand name Rixubis, the product is the first new recombinant coagulation factor IX product that FDA has approved for hemophilia B patients in more than 15 years, according to manufacturer Baxter International Inc.
FDA also approved the new recombinant product for use in controlling and preventing bleeding episodes in adults with hemophilia B and managing them perioperatively.
The initial dose of Rixubis, the labeling (PDF) states, should be calculated from the empirical finding that the circulating level of factor IX increases by 0.9 IU/dL after a 1-IU/kg dose.
Equations are provided in the labeling for calculating the initial dose to treat bleeding episodes and also the incremental recovery dose in previously treated patients. Tables in the labeling offer guidance for dosing the product to control and prevent bleeding episodes and manage patients perioperatively.
For the routine prophylaxis of bleeding episodes in adults previously treated with a coagulation factor IX product, the labeling recommends a twice-weekly dose of 40–60 IU/kg.
All doses are to be administered by i.v. bolus infusion.
Patients must not receive Rixubis if they have disseminated intravascular coagulation, signs of fibrinolysis, or a hypersensitivity to hamster protein. No hamster protein was added to the product during its manufacture or formulation, the labeling states, but the recombinant coagulation factor IX was produced by a hamster-derived cell line.
FDA said the most common adverse events reported for patients in the studies of the new recombinant coagulation factor IX product were taste distortion, pain in an extremity, and atypical blood test results.
Baxter will supply Rixubis in kits with the following contents: a single-use vial containing a nominal 250, 500, 1000, 2000, or 3000 IU of coagulation factor IX, a 5-mL vial of sterile water for injection, and a single-use needleless transfer device. Instructions, with diagrams, for reconstituting the drug product are provided in the labeling. Once the water has been added to the drug powder, the drug should be given within three hours.
The vials of drug powder should be stored at 2–8 °C and may be stored at room temperature, up to 30 °C, for up to six months after manufacture.
Baxter said Rixubis will be available to pharmacies in the fourth quarter of 2013.