Roctavian Receives Approval by the FDA for Severe Hemophilia A

The gene therapy Roctavian (valoctocogene roxaparvovec-rvox) for the treatment of adults with severe hemophilia A was approved by the US Food and Drug Administration (FDA) marking a significant milestone as the first gene therapy indicated for the rare disease, according to a statement from BioMarin Pharmaceutical.¹

"Adults with severe hemophilia A face a lifelong burden, with frequent infusions and a high risk of health complications, including uncontrolled bleeding and irreversible joint damage," study investigators Steven Pipe, MD, professor of pediatrics and pathology at the University of Michigan said.

There have been a few breakthroughs in treatment for the rare disease with recent evidence pointing to the efficacy of prophylactic therapies among others.² And while the Roctavian was first approved by the European Medicines Agency (EMA) in August 2022, it's just been granted approval in the US.¹

The approval of was based on the compelling results obtained from the global phase 3 GENEr8-1 study, which represented the largest and longest study of a gene therapy for hemophilia to date.

The study involved 134 patients who received Roctavian, with 112 patients having their baseline annualized bleeding rate (ABR) data prospectively collected over a period of at least six months on FVIII prophylaxis prior to treatment. The remaining 22 patients had retrospective baseline ABR data collected. All patients were followed for a minimum of 3 years.

According to the FDA, the 112 patients who had prospective baseline ABR data experienced a remarkable mean reduction of 52% after receiving the drug (2.6 bleeds/year) throughout the median 3-year follow-up period compared with their baseline ABR while on routine FVIII prophylaxis (5.4 bleeds/year).

An ABR of 35 in 13 patients during the periods when they were on prophylaxis was derived from the analysis. Additionally, These patients reported a significant reduction in the rate of spontaneous bleeds and joint bleeds following treatment with Roctavian.

The observed mean ABR for spontaneous bleeds was 0.5 bleeds/year, while for joint bleeds it was 0.6 bleeds/year. In comparison, their baseline rates while on routine factor VIII (FVIII) prophylaxis showed an observed mean ABR of 2.3 bleeds/year for spontaneous bleeds and 3.1 bleeds/year for joint bleeds.

Notably, the majority of study participants exhibited a continued response to Roctavian treatment beyond 3 years, without the need for regular prophylaxis supplementation. BioMarin plans to conduct an extension study to monitor the long-term effects of treatment, following all clinical trial participants for up to 15 years. In addition, post-approval studies will track individuals who receive the therapy in real-world settings for 15 years or more.

"The approval of Roctavian, as the first gene therapy for severe hemophilia A, has the potential to transform the way we treat adults based on years of bleed control following a single, one-time infusion,” Pipe said.

References:

1. U.S. Food and Drug Administration Approves BioMarin's ROCTAVIAN™ (valoctocogene roxaparvovec-rvox), the First and Only Gene Therapy for Adults with Severe Hemophilia A. News Release. BioMarin Pharmaceutical. June 29, 2023. https://prnmedia.prnewswire.com/news-releases/us-food-and-drug-administration-approves-biomarins-roctavian-valoctocogene-roxaparvovec-rvox-the-first-and-only-gene-therapy-for-adults-with-severe-hemophilia-a-301867403.html
2. Grossi G. Fitusiran Shows Promise as Prophylactic Therapy for Hemophilia A, B. HCPLive. April 3, 2023. https://www.hcplive.com/view/fitusiran-promise-prophylactic-therapy-hemophilia-a-b