Disc Medicine reported positive results from its pivotal Phase 3 APOLLO trial of bitopertin for erythropoietic protoporphyria (EPP), a rare disorder that can cause severe pain from light exposure. The company plans to resubmit its application for the drug by the end of 2026, with a U.S. regulatory decision anticipated by mid-2027.
The Watertown, Massachusetts-based biotech also reported progress in two other blood-disease programs and raised $486 million in net proceeds through an October public offering. It ended the third quarter with $682.8 million in cash, cash equivalents and marketable securities; the company said the offering extends its cash runway into 2030.
Bitopertin for EPP
- APOLLO met both of its primary goals, with statistically significant results compared with placebo:
- Bitopertin reduced whole-blood metal-free protoporphyrin IX, or PPIX, by 41.4%.
- During the sixth month of treatment, patients gained an average of 12.2 hours per month of time in sunlight without pain.
- The trial also met all secondary endpoints, including measures of phototoxic reactions and light tolerance. Exploratory quality-of-life measures were positive as well.
- Bitopertin was generally well tolerated. Dizziness was the most commonly reported treatment-emergent side effect, affecting 50% of patients in the treatment group; it was generally mild or moderate and transient. No treatment-emergent adverse events were above Grade 3.
- Disc plans to resubmit its New Drug Application to the FDA by year-end. The mid-2027 decision timing is the company’s expectation, not an approval.
Other pipeline programs
- Selcodebart for anemia associated with myelofibrosis: Disc expects to meet with the FDA by the end of the year to discuss Phase 2 results and the design of pivotal development. It plans to announce the agency’s feedback and its development plans by year-end. Updated RALLY-MF trial data are due at the American Society of Hematology meeting in December.
- Disc is also advancing selcodebart in a Phase 2 study for inflammatory bowel disease, with initial results expected in 2027.
- DISC-3405 for polycythemia vera: Initial Phase 2 RESTORE-PV results showed increased hepcidin and lower serum iron, alongside controlled hematocrit, reduced need for phlebotomy and improved symptoms. These results came from the study’s Q2 weekly-dosing cohort; the company did not provide numerical efficacy results in the announcement.
- DISC-3405 was generally well tolerated in RESTORE-PV. Reported adverse events were consistent with the underlying disease, and injection-site reactions were uncommon, mild and self-limited.
- Disc plans to present updated RESTORE-PV data, including initial efficacy results from a Q4 weekly-dosing cohort, at the December meeting. Initial results from a Phase 1b study of DISC-3405 in sickle cell disease are also scheduled for presentation there.
Financial position
- At September 30, Disc held $682.8 million in cash, cash equivalents and marketable securities.
- The company completed a public offering in October that generated approximately $486 million in net proceeds. Disc said the funds extend its cash runway into 2030.
The APOLLO result gives Disc a pivotal-trial outcome for bitopertin and a defined path toward an FDA review. The company is also preparing to advance selcodebart in myelofibrosis anemia and DISC-3405 in polycythemia vera, while its October fundraising adds substantial capital to support those programs and a potential bitopertin launch.