FDA Issues Complete Response Letter for Disc Medicine's Bitopertin in EPP
The FDA issued a Complete Response Letter for Disc Medicine's bitopertin application for erythropoietic protoporphyria, citing concerns over surrogate endpoints despite review under the accelerated approval pathway and Commissioner's National Priority Voucher pilot program.
The U.S. Food and Drug Administration has issued a Complete Response Letter to Disc Medicine regarding its New Drug Application for bitopertin, a treatment under investigation for erythropoietic protoporphyria (EPP). The CRL indicates that the FDA has completed its review of the application but cannot approve it in its current form.
Bitopertin has been under review for accelerated approval and as part of the Commissioner's National Priority Voucher (CNPV) pilot program. Accelerated approval relies on whether there is evidence of an effect on the proposed surrogate endpoint (% change in whole blood metal-free PPIX) and whether the proposed surrogate endpoint, including the magnitude of change, is reasonably likely to predict a clinical benefit.
The February 13 CRL advises Disc to pursue traditional approval of the erythropoietic protoporphyria drug based on clinical endpoints. The complete response letter suggests the challenges of the accelerated approval pathway may be too deeply ingrained to be smoothed over by the new Commissioner's National Priority Voucher.
Shares of Disc Medicine closed down 21.9% at $55.95 on Friday, having plunged as much as 39%, on news of the regulatory setback. This development highlights regulatory hurdles faced by pharmaceutical companies seeking approval for novel therapies.