USA — The Food and Drug Administration approved the first gene therapy for a type of hemophilia, giving people with the inherited disorder a treatment option that could potentially keep their bleeding under control for years while also allowing them to avoid the standard of care infusions.
The therapy, called Hemgenix, was developed by the Dutch biotechnology company UniQure for the less common “B” form of hemophilia, which is thought to account for about 15% of all patients with the disease.
Hemgenix is approved for the treatment of adults with hemophilia B who currently use factor IX prophylaxis therapy, or have current or historical life-threatening hemorrhage or have repeated, serious spontaneous bleeding episodes.
In the ongoing clinical trial, Hemgenix reduced the rate of annual bleeds and 94% of patients discontinued factor IX prophylaxis and remained prophylaxis-free.
Hemophilia B is a rare, lifelong bleeding disorder caused by a single gene defect that results in insufficient production of factor IX, a protein produced primarily by the liver that aids in the formation of blood clots.
Treatments for moderate to severe hemophilia B include prophylactic infusions of factor IX replacement therapy to temporarily replace or supplement low levels of blood-clotting factor.
While these treatments are effective, people with hemophilia B must adhere to infusion schedules for the rest of their lives.
As a result of the disease, they may still experience spontaneous bleeding episodes, limited mobility, joint damage, or severe pain.
Hemgenix allows people with hemophilia B to produce their own factor IX, potentially lowering the risk of bleeding.
CSL, an Australian pharmaceutical company licensed Hemgenix from UniQure and will market the drug.
Hemgenix has a list price of US$3.5 million, making it the most expensive one-time therapy in the world, overtaking Bluebird Bio’s Skysona, which had a list price of US$3 million following its approval in September.
According to the company, the price “will generate significant cost savings for the overall healthcare system and significantly reduce the economic burden of hemophilia B.”
The therapy is also under review in Europe. There, European regulators have approved BioMarin Pharmaceutical’s gene therapy for the more common hemophilia A.
The FDA is expected to make a decision on BioMarin’s Roctavian treatment next year. The FDA had planned to consult an advisory committee, but the company has announced that it will no longer do so.