The European Commission has approved the first gene therapy for the treatment of hemophilia B developed by biotech company CSL Behring.
The one-time gene therapy etranacogene dezaparvovec sold under the brand name Hemgenix is manufactured by UniQure Inc. and distributed by CSL Behring. The gene therapy is used to treat severe and moderately severe hemophilia B in adults without a history of Factor IX inhibitors.
Hemophilia B, also known as Christmas disease, is a rare genetic disorder caused by the lack of or defective clotting protein factor IX often due to a spontaneous mutation in the F9 gene. It affects more than 230,000 people worldwide, according to a global survey published in 2022.
Until now, patients were typically administered routine prophylaxis to maintain adequate clotting factor in the bloodstream to prevent prolonged bleeding, which is the major symptom of hemophilia B.
Mechanism and clinical trials
In its third phase of the Hope-B clinical trial, 54 hemophilia B patients were monitored for six months while undergoing regular prophylactic therapy. Patients then received a single infusion of Hemgenix which was administered intravenously, where the drug delivered a copy of the defective gene resulting in an increase in the mean Factor IX activity levels. This led to a 64% reduction of the annualized bleed rate, a key factor in assessing the efficacy of therapies in hemophilia trials.
Hemgenix gene therapy: ‘Important step forward in the treatment of hemophilia B’
The results of the trial brought about the European Commission’s decision to grant conditional marketing authorization (CMA) for Hemgenix.
Bill Mezzanotte, head of research and development and chief medical officer at CSL said: “The approval of Hemgenix in Europe is the essence of great science delivering a medicine that we believe can transform the treatment paradigm for both people living with hemophilia B and the healthcare professionals who treat them.”
Wolfgang Miesbach, head of coagulation disorders at the Comprehensive Care Center at University Hospital of Frankfurt expressed that this could change the lives of hemophilia patients.
Miesbach said: “This approval marks an important step forward in the treatment of hemophilia B, which could be transformative for people who are debilitated by bleeds into their muscles, joints and internal organs, alleviating the burden of lifelong intravenous infusions of Factor IX products.”
‘Hemgenix to remove the need for routine prophylaxis’
According to the European Medicines Agency’s Committee for Medicinal Products for Human Use, there is a need for new therapies beyond the lifelong routine infusions for hemophilia B patients.
“Data from the HOPE-B study demonstrate the potential of Hemgenix to remove the need for routine prophylaxis, by providing durable Factor IX activity, as well as improved bleeding outcomes and quality of life for people with hemophilia B,” said Miesbach.