Providing hemophilia patients with blood coagulation preparations is one of the priority tasks of the national health care system. In 2011, the first recombinant factor IX was created in Russia (rFIX, nonacog alpha, Innonafactor, GENERIUM JSC), that was previously studied for pharmacokinetic (PK) parameters, efficacy and safety in adult patients and adolescents over 12 years of age with severe and moderate hemophilia B. Objective of this open-label, prospective, multicenter, noncomparative clinical study was to study PK, efficacy and safety of Innonafactor in 12 patients aged 6 to 12 years with severe and moderate forms of hemophilia B (FIX activity less than 2%). The study included periods of screening, studies of PK parameters and treatment within 26±1 weeks, but not less than 50 days of administration of the studied drug. Nonacog alfa was administered in the study of PK parameters at a dose of 75 IU/kg, once, for prophylactic treatment – at a dose of 45±10 IU/kg, 2 times a week with an interval of 72–96 h. 30 minutes after administration of the studied drug, FIX activity increased to 73,93±13,35%, with a gradual decrease to 5,88±1,97% 72 hours after administration. The area under the «concentration ‒ time» curve in the section 0–72 h (AUC0–72) and with exponential extrapolation to infinity (AUC00‒∞) was 1573,41±407,16%*h and 1808,74 ± 437,59%*h respectively. Biological half-life (T1/2) was 28,11±8,60 hours. During preventive treatment there were 19 hemorrhagic episodes, 14 (74%) bleedings were post-traumatic and 5 (26%) bleedings were spontaneous. Mean number of bleeding episodes over the entire observation period was 1,9±1,4. Mean number of episodes of spontaneous bleeding that occurred within 72 hours after Innonafactor administration in patients with bleeding was 2,5±2,1. During the entire study period, patients received 942,5 thousand IU of the drug Innonafactor, 890,5 thousand IU were administered for prophylaxis and 52 thousand IU to stop bleeding on demand. Mean single dose of Innonafactor for prophylactic treatment was 46,24±5,86 IU/kg, for on-demand treatment – 49±13,1 IU/kg. Of the 19 registered bleeding episodes, 14 (73.7%) episodes required the administration of the studied drug; 5 (26,3%) bleedings stopped on their own. To stop one episode of bleeding, an average of 2,3±2,3 administration of nonacog alfa was required. At the end of the study, the proportion of hemophilia B patients with residual FIX activity of 2% or more was 92%. During the study, 14 adverse events (AEs) were registered in 7 (58,3%) patients. All reported AEs were not study drug related and did not require study drug withdrawal. Thromboembolic complications and immunogenic reactions were not registered. Thus, the data obtained indicate efficacy and safety of Innafactor both for prophylactic treatment and for on-demand treatment of bleeding in patients aged 6 to 12 years with severe and moderate hemophilia B.
Prophylactic treatment of bleeding episodes in children <12 years with moderate to severe hereditary factor X deficiency (FXD): Efficacy and safety of a high-purity plasma-derived factor X (pdFX) concentrate
