Ten years after dipping its toes into the gene therapy pool in a licensing deal with Spark Therapeutics, Pfizer has gained FDA approval for the acquired treatment.

The U.S. regulator has endorsed Beqvez (fidanacogene elaparvovec-dzkt) for adults with the bleeding disorder hemophilia B. It becomes the first FDA-approved gene therapy for Pfizer and the second in the indication following CSL and uniQure’s hemophilia B treatment Hemgenix, which became the world’s most expensive drug at $3.5 million when it was approved in 2022.

Pfizer had the chance to undercut its rival on price but decided to charge the same $3.5 million for Beqvez. The therapy will be available to patients this quarter, a spokesperson confirmed on Friday to Fierce Pharma.

According to the CDC, the current number of males with hemophilia living in the U.S. is around 33,000. Hemophilia A is more prevalent, with 12 cases per 100,000 U.S. males, while there are just 3.7 cases per 100,000 U.S. males for hemophilia B.