СПЕЦИФИКА МОЛЕКУЛЫ МОРОКТОКОГА АЛЬФА: РЕЗУЛЬТАТЫ ПРОСПЕКТИВНОГО МНОГОЦЕНТРОВОГО НАБЛЮДАТЕЛЬНОГО ИССЛЕДОВАНИЯ ЭФФЕКТИВНОСТИ И БЕЗОПАСНОСТИ У ПОДРОСТКОВ С ГЕМОФИЛИЕЙ A

Abstract

The main method of treatment for hemophilia A is replacement therapy with drugs of blood coagulation factors VIII (FVIII). The active use of biotechnological methods in the production of recombinant drugs contributes to the development and registration of new FVIII drugs. The results of clinical trials of drugs in children usually include a limited number of patients for a specific period of time. Post-marketing observational studies provide additional information on the results of using a new drug in patients in clinical practice. The objectives of the study were to collect and analyze data on the efficacy and safety of domestic recombinant FVIII with a deleted B-domain, moroctocog alfa (Octofactor, GENERIUM JSC) in the treatment of adolescents aged 12–18 years with hemophilia A in routine clinical practice. Materials and methods of research: a prospective multicenter open-label observational study of the results of using the Octofactor in adolescents with hemophilia A (№ OCF-HPA-N01) included 24 male patients with severe hemophilia A aged 12 to 18 years (mean age 14,8±1,7 years), who received moroctocog alfa in routine clinical practice. Enrollment in the study was carried out after the signing of the informed consent form by the parent of the minor patient and the minor patient aged 14 to 18 years, taking into account the results of the screening examination. The follow-up period was 52±4 weeks, which, presumably, was sufficient to achieve at least 100 days of moroctocog alfa administration. To assess the effectiveness, we analyzed the incidence of spontaneous bleeding that occurred within 48–72 h after drug administration; the severity of spontaneous bleeding against the background of prophylactic treatment with moroctocog alfa, the number of injections and the dose of the study drug for prophylactic treatment, as well as for treatment at the request of one episode of bleeding, taking into account its severity; the researcher's determination of the response to treatment of acute hemarthrosis according to the scale of the World Federation of Hemophilia (2020). To assess safety, the frequency and characteristics of adverse events (AEs) associated with drug administration were analyzed, including the frequency of formation of an inhibitor to FVIII. Results: during the study, 59 bleedings were recorded, of which 21 (36%) were spontaneous and 38 (64%) were post-traumatic. Among spontaneous bleeding episodes, 5 (24%) episodes occurred within 48–72 hours after administration of the study drug. Spontaneous bleeding within 48–72 hours after administration of Octofactor was absent against the background of prophylactic treatment in most patients (81%) and was observed rarely during the observation period (1–3 times) in the remaining 19% of patients. The median number of bleeding within 48–72 h after study drug administration was 1 episode over the follow-up period. The proportion of mild to moderate bleeding was 97 [88; 100]% among all types of bleeding and 100 [84; 100]% among spontaneous bleeding within 48–72 hours after administration of the Octofactor drug. The median of a single dose of Octofactor for preventive treatment was 2000 [1500; 2000] IU or 31,7 [25,6; 38,5] IU/kg, and with treatment on demand ‒ 2000 [2000; 3000] IU or 34,1 [28,8; 38,5] IU/kg per single injection. To stop the resulting bleeding required 1 [1; 2] introduction in a single dose of 3000 [2000; 4000] IU; the average dose was 4490 ÷ 4993 IU. When doctors subjectively assess the response to treatment of acute hemarthrosis on the scale of the World Federation of Hemophilia, an excellent response was noted in 9 (27%) episodes, good and moderate ‒ in 2 (6%) and 22 (67%) episodes, respectively. Lack of response to treatment of acute hemarthrosis with moroctocog alfa was not revealed in the study. During the study, 23 AEs were recorded in 13 (54%) patients not related to the study drug. Conclusion: thus, the obtained results of the study indicates the efficacy and safety of the Octofactor both the prophylactic treatment and treatment of on-demand bleedings in 12 to 18 year old patients with severe hemophilia A.