A new treatment option is available to certain patients with hemophilia A following the US Food and Drug Administration’s (FDA) approval of Genentech’s drug Hemlibra (emicizumab-kxwh). The medication is approved for treatment of patients with hemophilia A who have developed Factor VIII (FVII) inhibitor antibodies.
Hemophilia A is a hereditary blood disorder in which the FVIII blood clotting protein is either missing or defective. It is four times more common than hemophilia B and affects around 20,000 people in the United States. It occurs in approximately one in every 5,000 live births, according to the Centers for Disease Control and Prevention. Concentrated FVIII products are the inmost commonly used medications to treat hemophilia A, with around three-quarters of hemophilia A patients using a recombinant FVII product.
Hemlibra was approved following two phase III clinical trials, which evaluated the safety, efficacy, and pharmacokinetics of the drug. The trial demonstrated an 87 percent reduction in treated bleeds compared with patients who did not receive the prophylactic treatment. It the first approved treatment that works by bridging other factors in the blood to improve blood clotting. It is administered weekly through a subcutaneous injection to improve physical function and help patients manage their condition. Hemlibra was granted Priority Review, Breakthrough Therapy and Orphan Drug designation by the FDA.
Richard Pazdur, MD, acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, and director of the FDA’s Oncology Center of Excellence, commented: “Today’s approval provides a new preventative treatment that has been shown to significantly reduce the number of bleeding episodes in patients with hemophilia A with Factor VIII inhibitors.”
In patients with mild hemophilia, DDAVP (desmopressin acetate) is sometimes used to prevent muscle and joint bleeds. Other treatments available include antifibrinolytic medicines, such as Cyklokapron (tranexamic acid) and Amicar (epsilon aminocaproic acid), which prevent blood the break down of blood clots. Pain medication, steroids, and physical therapy may also be used to treat the symptoms of hemophilia.
Common side effects of Hemlibra include reactions on injection sites, headaches, and joint pain. The medication’s packaging also features a boxed warning alerting patients and physicians to the fact that severe blood clots have been observed in patients taking Hemlibra who were given rescue treatment to treat bleeds.