Following the recent news that BioMarin received a Complete Response Letter (CRL) from the Food and Drug Administration (FDA) indicating that its gene therapy for severe hemophilia A, ValRox (valoctocogene roxaparvovec), was not yet ready for approval;

Tajekesa Chapman, Senior Pharma Analyst at GlobalData, a leading data and analytics company, offers her view:

“ValRox was expected to be the first-to-market hemophilia gene therapy and BioMarin had set its hopes on launching the product this year. However, the FDA has recommended evidence of durability with two years of follow-up safety and efficacy data, and so delaying launch to 2022. The introduction of gene therapies will revolutionize the hemophilia treatment landscape and despite an initially slow uptake, will be a major driver for the hemophilia market, which is expected to reach $9.3bn by 2028, according to GlobalData. However, it comes as no surprise that these treatments will face market access issues due to the lack of long-term safety and efficacy data and the high cost of gene therapies targeting a small patient population.

“Curative options such as gene therapies provide permanent expression of clotting factor and are highly anticipated to eradicate the need for prophylactic factor replacement therapies – which severe hemophilia A patients heavily depend on to prevent spontaneous bleeding. A single gene therapy administration removes the burden of frequent dosing and administration by intravenous infusion and avoids the risk of developing inhibitors against replacement factors.”