The U.S. Food and Drug Administration (FDA) last week approved the first gene therapy to treat adults with hemophilia B, a genetic bleeding disorder resulting from missing or insufficient levels of a protein needed to make blood clot. About 15% of all hemophilia is hemophilia B. Other biopharmaceutical manufacturers are trying to create gene therapies for the more common type, hemophilia A, in which a different protein is missing.
FDA approved Hemgenix, manufactured by CSL Behring, on Nov. 22. According to several news organizations, an infusion will cost $3.5 million, making Hemgenix the world’s most expensive drug. “We are confident this price point will generate significant cost savings for the overall healthcare system and significantly lower the economic burden of hemophilia B,” the company told news outlets.
It is not known how long Hemgenix will work. CSL Behring said a treatment would last “for years.”
The Institute for Clinical and Economic Review (ICER) said in a report on Nov. 2 that fair pricing for Hemgenix should be no more than $2.96 million. ICER is an independent nonprofit organization that helps payers decide fair prices for drug and medical treatments.
CSL Behring told 340B Report last night it will offer 340B pricing on the product.
“CSL Behring will comply with all legal requirements applicable to the commercialization of Hemgenix, including those related to the 340B program,” a spokesperson said in a statement. “If a 340B covered entity, such as a hemophilia treatment center (HTC), purchases Hemgenix for administration to an eligible patient, the covered entity will receive the 340B price. Many HTCs are covered entities under the 340B program, which helps subsidize the cost of critical supportive coordinated care that HTCs provide to people with hemophilia and other bleeding disorders.”
Hemophilia Alliance, which represents more than 100 HTCs that participate in the 340B program, has not yet responded to a request for comment on Hemgenix’s approval.
FDA granted Hemgenix an orphan drug designation, which means that 340B pricing on it will be unavailable to critical access hospitals, rural referral centers, sole community hospitals, and free-standing cancer hospitals.
Currently, patients with severe hemophilia B require lifelong infusions of factor IX, a protein that helps blood clots form. Hemgenix enables people living with hemophilia B to produce their own factor IX, CSL Behring said. It said 51 out of 54 patients in a clinical trial of the drug were able to discontinue use of factor IX replacement therapy.
ICER said patients treated with Hemgenix (etranacogene dezaparvovec) “had an 80% reduction in treated joint bleeds and similar reductions in other bleeds when compared with their bleeding rates on factor prophylaxis prior to gene therapy. However, there is still considerable uncertainty about the duration of benefit and the risk of uncommon harms.”
CSH Behring said in a news release that FDA’s approval of Hemgenix “provides a new treatment option that reduces the rate of annual bleeds, reduces or eliminates the need for prophylactic therapy and generates elevated and sustained factor IX levels for years after a one-time infusion.”
“Gene therapy for hemophilia has been on the horizon for more than two decades,” said Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research. He said Hemgenix’s approval “represents important progress in the development of innovative therapies for those experiencing a high burden of disease associated with this form of hemophilia.”