Emicizumab Prophylaxis in Patients with Severe Hemophilia A: Insights from A Resource Limited Country

Abstract

Emicizumab is a humanized, bispecific monoclonal antibody that connects active factor IX and X to replace the function of absent factor VIII, restoring hemostasis. It has a long half-life with a subcutaneous route of administration and high bioavailability. Here, we assessed the efficacy of Emicizumab prophylaxis in terms of efficiency, safety, and quality of life of severe hemophilia A (HA) patients with and without inhibitors before and after this treatment. Methods In this prospective study, severe HA patients were recruited from January 2022 to June 2023. Inhibitor positive and inhibitor negative patients with annual bleeding rate (ABR) 8 or greater and past histories of bleeding like intra-cranial, intra-abdominal, and pseudo-tumors were included. Emicizumab loading dose was 3 mg/kg in the first 4 weeks, and the maintenance dose was started at week 5 at 6 mg/kg/month. Patients’ detailed bleeding history and demographics were recorded. The five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) was used to evaluate patients’ HRQoL. Furthermore, Hemophilia Joint Health Score (HJHS) and Functional Independence score in Hemophilia (FISH) were applied for the assessment of joints at different time points. Results were analyzed by SPSS version 21. Results A total of 36 HA male patients with the mean age of 19.7 ± 14.42 years were recruited in the study; among them, 19 patients were inhibitor positive, while 17 were negative. Patients clinically presented with bleeding symptoms which included: hemarthrosis 95%, GI bleeding 13.8%, and bruises and gums bleeding 13.8%. Significant reduction was observed in the bleeding episodes after the therapeutic intervention, and joints assessment and Euro-Quality-of-life Visual Analog Scale showed a significant improvement in health after treatment. Similarly, there was a remarkable reduction in bleeding episodes and improved quality of life among HA patients. The ABR decreased from 53.6% episodes per year prior to treatment to 2.4% during Emicizumab therapy. Prior to initiating Emicizumab therapy, participants exhibited an average FISH score of 16 and HJHS score of 10, indicating moderate limitations due to joint-related issues. After treatment, the mean FISH score improved to 9 and HJHS score to 4 reflecting a substantial enhancement in participants’ ability to perform daily activities ( P < 0.057). Conclusion Our results showed that HA patients on prophylactic treatment with Emicizumab were less restricted and had improved quality of life due to marked decrease in bleeding episodes which resulted in improved health and social lives. In addition, it was well tolerated, and no participant discontinued treatment because of adverse events.