BioMarin Announces Positive Phase 3 Study Data for Valoctocogene Roxaparvovec

The phase 3 trial currently includes 134 participants with hemophilia A, all of whom have received a single dose of the gene therapy.

BioMarin recently announced positive updates from its ongoing phase 3 GENEr8-1 study of valoctocogene roxaparvovec, an investigational gene therapy for the treatment of adults with severe hemophilia A. The trial currently includes 134 participants, all of whom have received a single dose of the therapy and have been observed for at least one year post treatment.

An analysis of GENEr8-1 data showed that at an average follow up of 71.6 weeks, annualized bleeding rate (ABR) was reduced by 84%, from 4.8 ABR in the pre gene therapy period, to 0.8 ABR in the post gene therapy period. Further, 80% of participants were free of bleeding symptoms starting at week five after receiving valoctocogene roxaparvovec.

The data also indicated a significant drop in requisite factor VIII (FVIII) product usage amongst trial participants, with average annualized FVIII infusions reduced by 99% post administration of the investigational therapy.

According to a BioMarin press release, the therapy has also been well tolerated overall by the 134 study participants, none of which have developed FVIII inhibitors or experienced thromboembolic events.

“This is the first statistical evidence demonstrating ABR superiority in a gene therapy trial. These data give us confidence in this groundbreaking alternative to existing therapies and bring us one step closer to a potential new treatment choice to fulfill an unmet medical need for people with hemophilia A,”said Steven W. Pipe, MD, Professor of Pediatrics and Pathology, Coagulation Director, Special Coagulation Laboratory Laurence A. Boxer, MD Research Professor of Pediatrics and Communicable Diseases Department of Pathology Michigan Medicine at the University of Michigan and investigator in the Phase 3 study. “This data set adds to the growing body of scientific and clinical data around valoctocogene roxaparvovec gene therapy for hemophilia A and creates the possibility for a new treatment paradigm.”

BioMarin continues to work with the U.S. Food and Drug Administration (FDA) to obtain eventual marketing approval for valoctocogene roxaparvovec, albeit within a timeline that shifted dramatically in the summer of 2020. This past August the FDA issued a Complete Response Letter, which essentially put approval of the Biologics License Application (BLA) for valoctocogene roxaparvovec on hold until the phase 3 study is completed and two-year follow-up safety and efficacy data on all study participants is submitted.

Source: BioMarin press release dated January 10, 2021