BioMarin Pharmaceutical received approval from the Food and Drug Administration (FDA) for its gene therapy, Roctavian (valoctocogene roxaparvovec) for severe haemophilia A. This marks a significant milestone as ROCTAVIAN becomes the first and only gene therapy approved for this condition in the U.S for adults. The treatment offers a one-time, single-dose infusion to control bleeding in adults with severe haemophilia A effectively.
The FDA's decision to approve Roctavian was based on the extensive Phase 3 study, which provided evidence of the therapy's durability, efficacy, and safety. This study was the largest and longest for gene therapy targeting haemophilia. Over three years, the majority of patients who received Roctavian continued to respond positively to the treatment.
Hemophilia A is a genetic condition characterized by a deficiency in factor VIII (FVIII), a protein essential for blood clotting. Individuals with severe haemophilia risk experiencing painful and life-threatening bleeds, which can occur spontaneously. The standard treatment involves regular infusions or injections to maintain adequate blood clotting factor levels. However, Roctavian offers a novel approach by replacing the faulty gene responsible for FVIII production. This allows individuals to produce their own FVIII, thereby reducing the frequency of bleeding episodes.
Roctavian is manufactured at BioMarin's facility in Novato, California, one of the world's largest gene therapy manufacturing sites. The company is confident that it can meet the commercial demand for Roctavian throughout its lifecycle.
The FDA's approval of Roctavian was supported by data from the GENEr8-1 study, a Phase 3 trial involving a global cohort of patients. Out of the 134 patients who received Roctavian, 112 had baseline bleeding rate data collected prospectively over a minimum of six months on FVIII prophylaxis before treatment. The remaining 22 patients had retrospective data. The results showed that these patients experienced a significant reduction in annualized bleeding rate (ABR) after receiving Roctavian compared to their baseline ABR while on routine FVIII prophylaxis.
Specifically, the analysis indicated a mean ABR reduction of 52% (2.6 bleeds per year) through the three-year follow-up period, compared to a baseline ABR of 5.4 bleeds per year. Patients also reported a considerable decrease in spontaneous and joint bleeds rate after receiving Roctavian. The observed mean ABR for spontaneous bleeds was 0.5 per year, down from 2.3 per year on routine prophylaxis, while the observed mean ABR for joint bleeds decreased to 0.6 per year from 3.1 per year.
The study further revealed that the positive response to Roctavian treatment persisted beyond the three-year mark, with most participants not requiring additional regular prophylaxis.
BioMarin remains committed to long-term monitoring of treatment effects. An extension study will follow all participants in the clinical trial for up to 15 years, while post-approval studies will track individuals treated in real-world settings for 15 years or more.
In addition, recent data presented at the International Society on Thrombosis and Haemostasis (ISTH) 2023 Congress showcased the three-year analysis of the GENEr8-1 study. These results demonstrated an 82.9% reduction in treated bleeds overall compared to baseline and a 96.8% reduction in FVIII usage.
The approval of Roctavian represents a significant advancement in treating severe haemophilia A, offering patients a potentially life-changing therapy that can control bleeding with a one-time infusion.