Clinical and Applied Thrombosis/Hemostasis (May 2025)
Evaluating the Safety and Efficacy of Concizumab in Hemophilia A/B Patients: A Systematic Review
Abstract
Background Hemophilia A and B are X-linked recessive bleeding disorders caused by deficiencies of coagulation factors VIII and IX, respectively. These conditions lead to spontaneous bleeding, joint damage, inhibitor development, and the burden of frequent intravenous infusions. Concizumab, a monoclonal antibody targeting tissue factor pathway inhibitor (TFPI), is a novel non-factor therapy that enhances thrombin generation. This systematic review evaluates the efficacy and safety of concizumab prophylaxis in patients with hemophilia A and B. Methods This systematic review was conducted in accordance with PRISMA guidelines. Randomized controlled trials (RCTs) assessing the use of concizumab in hemophilia A or B were identified through a comprehensive search of electronic databases. Outcomes of interest included annualized bleeding rate (ABR), thrombin generation, bleeding episodes, immunogenicity, and adverse events. The Cochrane Risk of Bias Tool 2.0 was used for quality assessment. Results Five studies were included. Concizumab prophylaxis was associated with a notable reduction in ABR, with reported decreases from 9.4 to 1.3 episodes/year and from 19.6 to 2.9 episodes/year in hemophilia A, and from 14.9 to 1.6 episodes/year in hemophilia B. Thrombin generation increased in a dose-dependent manner and stabilized by week 24. Across all studies, bleeding episodes were significantly reduced. Adverse events were primarily mild to moderate. No thromboembolic events were reported. Conclusion Concizumab appears to be an effective and safe prophylactic treatment for patients with hemophilia A and B, demonstrating consistent reductions in bleeding rates and enhanced thrombin generation. Further long-term studies are warranted to establish its sustained safety and efficacy.