BioMarin’s Roctavian becomes first FDA-approved gene therapy for severe haemophilia A

The FDA has approved BioMarin’s Roctavian (valoctogene roxaparvovec) for adults with severe haemophilia A. Currently, around half of the patients who have the most severe form of haemophilia A undergo intravenous Factor VIII (FVIII) infusions two to three times per week, or receive a bispecific monoclonal antibody one to four times per month. However, many patients still suffer from bleeds, leading to incapacitating joint damage. Addressing this unmet need, BioMarin’s Roctavian is administered as a solitary infusion and delivers a functional gene that enables the body to independently produce FVIII. This innovative approach reduces the treatment burden by eliminating the need for continuous haemophilia prophylaxis.

The authorisation was granted based on the results of the Phase III GENEr8-1 clinical trial. This study assessed the effectiveness and safety of Roctavian in a group of 134 adult males afflicted with severe haemophilia A. Each participant was given a solitary intravenous infusion of Roctavian and subsequently monitored for a period of three years. Among the 134 patients enrolled in the study, baseline annualised bleeding rate (ABR) data was collected for 112 patients prospectively, covering a minimum period of six months while they were on FVIII prophylaxis before receiving Roctavian. The remaining 22 patients had their baseline ABR data collected retrospectively. After receiving Roctavian, the 112 patients for whom six-month baseline ABR data was prospectively collected witnessed a noteworthy average reduction of 52% in ABR (equivalent to 2.6 bleeds per year) during the follow-up period. This reduction is in comparison to their baseline ABR while receiving routine FVIII prophylaxis (equivalent to 5.4 bleeds per year). Moreover, these patients reported a significant decrease in the occurrence of joint pain and spontaneous bleeds following their treatment with Roctavian.

BioMarin’s Roctavian will face a distinctive challenge, setting it apart from the numerous gene therapies already approved by the FDA. Unlike therapies that are targeted at conditions with limited alternatives, Roctavian enters a competitive market saturated with many successful haemophilia A treatments; one such example is Roche’s blockbuster antibody drug Hemlibra (emicizumab-kxwh), which generated sales of $4m in 2022. Accordingly, GlobalData estimates global sales of $1.21bn by 2029 for Roctavian.