CSL Behring's Hemgenix has been approved by US regulators, however the drug costs $3.5m per dose

CSL Behring’s haemophilia B gene therapy has recently been approved by US regulators, however the treatment has an enormous price tag. Costing $3.5m per dose, the one-off infusion therapy has become the world’s most expensive medicine currently available.

CSL Behring’s Hemgenix is a one-dose treatment that appeared to reduce the number of bleeding events by 54% over the course of a year. The treatment also seemed to free 94% of patients from expensive and time-consuming infusions of Factor IX, which is the current standard of care for the often fatal condition.

Pricing has long been a problem for novel medicines, with high prices for treatments such as Biogen Inc’s Alzheimer’s drug Aduhelm and Bluebird’s Zynteglo.

Treatments for haemophilia have been developing, however therapies to prevent bleeding can often negatively impact a patient’s quality of life, according to Peter Marks, at the FDA’s Center for Biologics Evaluation and Research. Marks continues that Hemgenix signals some important progress in the development of treatments for patients with the disease. Current standard of care treatments involve infusing missing proteins, knownasclottingfactors,sothebodycanformclots and stop the bleeding. Hemgenix, however, provides a gene that can produce the missing proteins into the liver so it can make the proteins needed.

Brad Loncar, a biotechnology investor and CEO of Loncar Investments, commented: “While the price is a little higher than expected, I do think it has a chance of being successful because 1) existing drugs are also very expensive and 2) haemophilia patients constantly live in fear of bleeds. […] A gene therapy product will be appealing to some.”