The FDA has rejected Disc Medicine's therapy for a rare blood disorder, the first experimental drug to pass the new Rapid Drug Review Program. It is a medicine called bitopertin intended for the treatment of erythropoietic protoporphyria (EPP), including X-linked protoporphyria. EPP is a rare genetic disease causing severe reactions to sunlight exposure, such as excruciating pain, swelling and burning, and leads to severe liver complications in 20-30% of patients. The drug previously received Orphan Drug designation and Rare Pediatric Disease designation from the FDA. Disc Medicine Voucher has received a national priority designation from the FDA commissioner, part of a program established in June 2025 to accelerate the development of medicines that address US national health priorities. This voucher reduces application review times to 1-2 months and includes improved communication and rolling review processes. The new drug application was filed by Disc Medicine in September 2025. The company's stock rose 19.7% in aftermarket trading following the voucher announcement.[1][2]