FAIRLESS HILLS, PA (AP) — Investors fled drug developer BioMarin in droves on Wednesday, driving shares down by a third after U.S. regulators rejected the company’s potentially game-changing gene therapy for hemophilia A patients.
The rejection late Tuesday by the U.S. Food and Drug Administration means the San Rafael, California-based company will have to complete an ongoing late-stage patient study, delaying possible approval for a couple years.
The therapy, which could have freed hemophilia A patients from frequent infusions of a blood-clotting therapy to prevent dangerous internal bleeding, had been highly anticipated by doctors, patients and investors.
Called valoctocogene roxaparvovec, or valrox for short, it would have been the first gene therapy approved in the U.S. for any type of hemophilia, a rare, genetic bleeding disorder in which people don’t have enough of a clotting protein called Factor VIII and repeatedly suffer internal bleeding.
Biomarin’s therapy was meant to free patients with severe hemophilia A from 100 to 150 IV infusions of Factor VII per year to prevent painful, spontaneous bleeding into joints and muscles, which can cause permanent damage to them.
However, questions about whether the therapy would work for a lifetime or just several years arose recently, amid rumors that Biomarin might set a price tag as high as $3 million per patient.
In midday trading, Biomarin Pharmaceutical Inc. shares plunged $40.33, or just over 34%, at $78.21.