From the Guidelines
Hemophilia B patients should be treated with prophylaxis using either purified plasma-derived or recombinant FIX concentrates, with a preference for extended half-life recombinant FIX due to its reduced burden and potential for less frequent injections 1.
Treatment Overview
Hemophilia B is a genetic bleeding disorder caused by a deficiency in clotting factor IX, primarily affecting males and inherited in an X-linked recessive pattern. Patients experience prolonged bleeding after injuries, surgeries, or sometimes spontaneously, particularly in joints and muscles. The severity depends on the level of factor IX activity, with severe cases having less than 1% activity.
Treatment Options
Treatment centers on factor IX replacement therapy, which can be administered on-demand for bleeding episodes or as prophylaxis to prevent bleeds. Specific factor IX products include:
- Recombinant factors like Alprolix, BeneFIX, and Rixubis
- Plasma-derived concentrates For mild cases, desmopressin (DDAVP) may help. Dosing depends on the severity of bleeding and the patient's weight, typically ranging from 20-100 IU/kg.
Comprehensive Care
Comprehensive care includes:
- Regular monitoring at specialized hemophilia treatment centers
- Genetic counseling for families
- Management of complications like joint damage Gene therapy represents a promising emerging treatment that may provide long-term factor IX production. Early diagnosis and treatment are essential to prevent long-term joint damage and improve quality of life, as highlighted by the international society on thrombosis and haemostasis clinical practice guideline for treatment of congenital hemophilia A and B 1.
Considerations for Prophylaxis
The choice between plasma-derived and recombinant FIX concentrates for prophylaxis should consider patient preference, costs, availability of specific concentrates, and suitability of use of either option, with the understanding that plasma-derived FIX concentrates must meet current safety standards 1.
From the FDA Drug Label
Profilnine, Factor IX Complex, is indicated for the prevention and control of bleeding in patients with factor IX deficiency (hemophilia B). Profilnine is a mixture of the vitamin K-dependent clotting factors IX, II, X, and low levels of VII. A clinical study that evaluated twelve subjects with hemophilia B indicated that, following administration of Profilnine, the factor IX in vivo half-life was 24.68 ± 8.29 hours and recovery was 1.15 ± 0.16 units/dL per unit infused per kg body weight.
Hemophilia B is a condition that can be treated with factor IX (IV), as indicated by the drug labels 2 and 2. The drug labels state that factor IX is used for the prevention and control of bleeding in patients with factor IX deficiency (hemophilia B).
- The half-life of factor IX is approximately 24.68 hours.
- The recovery of factor IX is approximately 1.15 units/dL per unit infused per kg body weight.
From the Research
Definition and Treatment of Hemophilia B
- Hemophilia B is a rare hereditary hemorrhagic disorder characterized by deficiency of the clotting factor IX (FIX) 3, 4.
- The mainstay of treatment of hemophilia B consists of replacement therapy, with several plasma-derived and recombinant FIX products commercially available 3, 5.
- Hemophilia B patients experience mild-to-severe bleeding complications according to the degree of FIX defect 3, 4.
Current Management and Emerging Issues
- The current management of hemophilia B patients involves analyzing the results of the most important clinical trials 3.
- Recent advances in the production of new FIX molecules aim to improve the clinical management of hemophilia B patients 3, 4, 5.
- The development of recombinant FIX products with extended half-lives will further improve the therapeutic armamentarium for hemophilia B patients 4, 5, 6.
Safety and Efficacy of Recombinant FIX Products
- Recombinant human factor IX (rFIX) has been evaluated for safety and efficacy in hemophilia B patients, showing promising results 7.
- rFIX is safe and effective for the treatment of hemophilia B, with a lower risk of transmission of blood-borne pathogens compared to plasma-derived FIX concentrates 7.
- Alprolix (recombinant Factor IX Fc fusion protein) is a therapeutic Factor IX preparation with a prolonged half-life, approved for use in the clinic for patients with hemophilia B 6.