The US Food and Drug Administration (FDA) has approved BioMarin Pharmaceutical’s Roctavian (valoctocogene roxaparvovec-rvox) as the first gene therapy for adults with severe haemophilia A.
Approximately 2,500 patients are expected to be eligible to receive the adeno-associated (AA) virus vector-based therapy, which is specifically indicated for use in those without pre-existing antibodies to AA virus serotype 5.
People living with haemophilia A lack sufficient functioning Factor VIII protein to help their blood clot, putting them at risk of painful and potentially life-threatening bleeds.
Patients with the most severe form of the disease, which make up around 50% of the haemophilia A population, are currently treated with intravenous Factor VIII infusions two to three times per week, or a bispecific monoclonal antibody one to four times per month.
Despite these prophylactic regimens, many patients continue to experience breakthrough bleeds, resulting in progressive and debilitating joint damage.
BioMarin’s Roctavian, which is administered as a one-time infusion, delivers a functional gene that is designed to enable the body to produce Factor VIII on its own without the need for continued haemophilia prophylaxis, relieving patients of their treatment burden.
The FDA’s decision was supported by positive results from the phase 3 GENEr8-1 study, in which patients receiving the therapy demonstrated a mean reduction in the annualised bleeding rate of 52% compared to baseline.
The majority of patients involved in the study continued to respond to treatment through year three and beyond without supplemental use of regular prophylaxis, BioMarin said.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said: “[The] approval represents an important advance in providing treatment options for patients with this bleeding disorder, and treatment with gene therapy may reduce the need for ongoing routine therapy.”
Dr Steven Pipe, an investigator in the phase 3 GENEr8-1 study, said: “The approval of Roctavian, as the first gene therapy for severe haemophilia A, has the potential to transform the way we treat adults based on years of bleed control following a single, one-time infusion.”
Before the FDA’s decision, the therapy was first approved by the European Commission in August 2022.