Hemgenix Marks Most Expensive Treatment Ever and First Gene Therapy for Hemophilia B

In a historic moment, CSL Behring’s one-time gene therapy infusion, Hemgenix, received FDA approval to treat eligible adults with Hemophilia B. The revolutionary therapy marks the first and only gene therapy for the condition, but it will come at a hefty cost. CSL announced Hemgenix would cost about $3.5 million, making it the most expensive treatment on the market.

Innovative One-Time Treatment for a Lifelong Disease

Hemophilia B is a rare bleeding disorder resulting in reduced production of factor IX, a protein responsible for blood clots. Current therapies typically include factor IX replacement therapy, which entails a lifelong schedule of infusions. 

CSL designed Hemgenix as a one-time infusion that prompts a patient’s system to create factor IX. The company said Hemgenix reduces or eliminates the need for prophylactic therapy and can elevate factor IX levels for years after the initial infusion. 

The FDA based the approval on the ongoing HOPE-B trial, where Hemgenix allowed patients to produce mean factor IX activity of 39% at six months and 36.7% at 24 months. Seven to 18 months after treatment, patients, on average, saw a 54% reduction in bleeding events. Additionally, 94% of patients treated with the gene therapy discontinued prophylactic therapy entirely. 

Kim Phelan, CEO of The Coalition for Hemophilia B, said, “We are thrilled to witness this milestone in hemophilia B treatment. Over the years, we have seen a variety of advancements for the hemophilia community, but gene therapy is the first treatment option to offer those living with hemophilia B–and caregivers–the possibility of freedom from the need for regular, ongoing infusions.”

Related Article: Bluebird Bio’s Zynteglo Becomes First FDA-Approved Gene Therapy For Beta-Thalassemia

A Big Price for a Revolutionary Treatment

Despite Hemgenix’s potential value to the Hemophilia B community, the gene therapy will cost upwards of $3.5 million. Still, private and public insurers in the U.S. will likely bear most of the costs associated with the treatment. 

All gene therapies are expensive due to the research, development, and costs to produce the products, and price tags of greater than $2 million are becoming more common. 

In August, Bluebird Bio broke the previous record for the most expensive gene therapy with its beta-thalassemia treatment, Zynteglo. The drug costs $2.8 million, but Bluebird said it would reimburse 80% of the cost if the drug fails to produce durable transfusion. 

CSL argues that despite the huge cost, Hemgenix will save on healthcare costs associated with factor IX replacement, prophylactic therapies, and expenses related to bleeding incidents. 

Hemgenix is breaking multiple barriers as the first gene therapy for Hemophilia B and the most expensive therapy on the market. Regardless of the costs, CSL is playing a pivotal role in ushering in a new generation of therapeutics that will significantly impact pharma and the healthcare industry.

Author

Reed Slater