Clinical features and treatment of hemophilia B

Hemophilia B – a deficiency of blood coagulation factor IX (FIX) – is one of the most common hereditary coagulopathies along with hemophilia A and von Willebrand disease. As in hemophilia A, patients with hemophilia B require prophylactic treatment to prevent the development of bleeding and arthropathy, and there is a number of unsolved problems in their treatment. At the same time, the arsenal of drugs for the treatment of hemophilia B is significantly smaller compared to hemophilia A, and therefore the emergence of new drugs for the treatment of FIX deficiency is of great practical importance for doctors and patients. The article provides information about the pathogenesis and clinical course of hemophilia B, discusses the most promising areas in the treatment of this disease, such as innovative recombinant FIX molecules, rebalancing and gene therapy. In addition, we outlined clinical and laboratory criteria indicating the necessity to change treatment in patients with hemophilia B as well as presented clinical cases of patients who were switched to long-acting FIX products. The patients' parents gave their consent to the use of their children's data for research purposes and in publications.