Future perspectives on patients with hemophilia and inhibitors

Abstract

In recent years, hemophilia treatment has undergone a paradigm shift: nonfactor agents can prevent bleeding regardless of the presence of inhibitors, and clinical trials of gene therapy are underway. However, currently available nonfactor agents also require the concomitant use of coagulation factor agents for hemostatic management during breakthrough bleeds or in the perioperative period in patients with hemophilia A, and thrombosis sometimes occurs in some cases with the concomitant use of these agents. Moreover, inhibitors develop in patients with nonsevere hemophilia A, and even patients who do not require prophylaxis therapy suddenly experience difficulty in maintaining hemostasis. Thus, inhibitors remain an important issue in hemophilia care. Immune tolerance induction (ITI) therapy is the only treatment that aims for eradicating inhibitors, and the current status of this therapy in Japan (J-ITI Registry) has been reported. Factors related to the development of inhibitors had also been studied prospectively or retrospectively, mainly in Europe and U.S. In Japan, the J-HIS study has recently shown the relationship between F8 mutations and the risk of inhibitor development in patients with hemophilia A. Basic research on inhibitor development is also being conducted extensively. We hope that the information obtained from these studies will fully help establish a treatment strategy for eradicating inhibitors.