Statistically significant improvement in hemophilia A control: a retrospective analysis of the effectiveness and safety of emicizumab in children with severe and inhibitor forms of hemophilia A

Abstract

   Hemophilia A presents a serious problem, especially in its severe and inhibitor forms, leading to severe bleeding and complications. The importance of studying the effectiveness and safety of new treatment approaches, particularly emicizumab, is undeniable for improving the quality of life of patients.   Aim: to evaluate the effectiveness and safety of emicizumab in the prevention of bleeding in children with severe and inhibitor forms of hemophilia A.   Ethical approval was not required since the study only involved the use of generalized retrospective data obtained during routine clinical practice. All data were depersonalized. A retrospective analysis of medical records of 45 children treated at the Morozov Children's Hospital from 2006 to 2022 was carried out. The study included two cohorts: those with severe hemophilia A and those with inhibitor forms. The analysis included an assessment of the frequency of bleeding and hemarthrosis episodes, hospital admissions, and adverse reactions. The analysis included data from 45 patients with hemophilia A who underwent treatment with emicizumab from 2018 to 2022. Of these, 30 children had a severe form of hemophilia A, and 15 had an inhibitor form. The median follow-up period for a severe form was 17 months, ranging from 12 to 23 months, while for an inhibitor form, it was 32 months, with a range of 11 to 51 months. In the group with severe hemophilia A, a statistically significant (p < 0.001) reduction in the frequency of all types of bleeding was observed: 96.7 % of children had no episodes of hemarthrosis during emicizumab therapy, compared to 46.7 % of patients previously treated with FVIII concentrates. No spontaneous hemarthrosis was registered. Similar results were observed in the group with an inhibitor form of hemophilia A: 93.3 % of children had no hemarthrosis episodes while using emicizumab compared to 13.3% during previous treatment with bypassing agents. Over the entire follow-up period, there were 3 bleedings in the cohort of children with severe hemophilia A and 1 bleeding in the cohort of children with inhibitor hemophilia A. Prior to the use of emicizumab, out of 391 bleeding episodes that occurred in 45 children, 218 were spontaneous. Adverse events were recorded in 7 children, manifesting as erythema at the injection site after the first or first and second emicizumab injections and resolving spontaneously. There were no other adverse events; 90 % of children with severe hemophilia A and 73.3 % of children with inhibitor hemophilia A did not report any adverse events during the use of emicizumab. Emicizumab demonstrates high effectiveness and safety in the treatment of children with severe hemophilia A, both with and without inhibitors. The drug significantly reduces the frequency of bleeding episodes and improves the quality of life of patients.