On Tuesday, November 22nd, 2022, the United States Food and Drug Administration approved Hemgenix, a new drug to treat hemophilia. Hemophilia is a lifelong & rare blood disorder where the blood cannot make the proteins needed to form a blood clot. It can result in bleeding within one's joints, in one's head and brain (can result in seizures and paralysis), and death can potentially occur if not treated properly. Hemophilia affects males more than females and can affect around 1 in every 5,000 male births.1 See the video below for an in-depth explanation of what hemophilia is.
Before this new drug, hemophilia treatment included two parts - management of emergency bleeding and prophylaxis (basically taking medications to prevent something from happening, as opposed to treating something after happening.)
Patients presenting to the emergency room with acute bleeding in the context of hemophilia are usually given high-dose clotting factor concentrate (CFC) and even undergo surgery to drain the blood out from places blood should not be. Prophylactic treatment results in lower hospitalization and increases the quality of life. Potential agents used for prophylaxis are desmopressin, tranexamic acid, and epsilon aminocaproic acid.2 This all has potentially changed with the introduction of Hemgenix.
Gene therapy is a fantastic discovery, especially Hemgenix, since it can provide the body with the tools to make factor IX, a necessary protein in the clotting cascade. It works by having a vector carry the gene variant of factor IX to cells in the liver, and once the liver receives the variant, the body can produce factor IX. 3
Peter Marks, M.D., Ph.D., and director of the FDA's Center for Biologics Evaluation and Research, stated that, "[The] approval provides a new treatment option for patients with Hemophilia B and represents important progress in the development of innovative therapies for those experiencing a high burden of disease associated with this form of hemophilia.".
However, nothing is ever "no strings attached." The drug was approved at $3.5 million per dose, which is potentially a barrier for access to some. There are also a plethora of potential side effects of Hemgenix, with a few including infusion reactions (potential symptoms include headaches, abdominal pain, increased blood pressure, and rash) and elevated liver enzymes. These possible side effects, along with the potential cost of the drug, may be a hurdle for patients wishing to use this medication for their disease.
References
1 https://www.cdc.gov/ncbddd/hemophilia/facts.html
2 Mehta P, Reddivari AKR. Hemophilia. [Updated 2022 Sep 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK551607/
3 https://www.cslbehring.com/newsroom/2022/fda-hemgenix