Disc Medicine Receives FDA Complete Response Letter for Bitopertin, Reports Q4/FY25 Results

summarizeSummary

Disc Medicine announced Q4 and full-year 2025 financial results and pipeline updates, including a significant FDA Complete Response Letter for its lead candidate, bitopertin, alongside positive data for DISC-0974 and a strong cash runway.

check_boxKey Events

• FDA Issues Complete Response Letter (CRL) for Bitopertin

  The U.S. Food and Drug Administration (FDA) issued a Complete Response Letter for bitopertin in February 2026, citing insufficient evidence of association between percent change in PPIX and sunlight exposure-based endpoints, delaying potential approval.

• Bitopertin Phase 3 APOLLO Study Progress

  The Phase 3 APOLLO clinical trial of bitopertin in erythropoietic protoporphyria (EPP) is expected to complete enrollment in March 2026, with topline data anticipated in Q4 2026. A resubmission to the FDA is planned after APOLLO completion, with a decision expected by mid-2027.

• Positive Initial Phase 2 Data for DISC-0974

  Initial data from the Phase 2 RALLY-MF trial of DISC-0974 in patients with anemia of myelofibrosis (MF) demonstrated positive, durable benefits on hemoglobin and transfusion burden across various patient subgroups.

• Strong Financial Position and Cash Runway

  The company reported $791.2 million in cash, cash equivalents, and marketable securities as of December 31, 2025, which is expected to fund operational plans into 2029.

auto_awesomeAnalysis

The FDA's Complete Response Letter (CRL) for bitopertin is a significant setback, delaying potential approval and introducing uncertainty for a key pipeline asset. While the company plans to resubmit after the Phase 3 APOLLO study, this extends the timeline for market entry. However, positive Phase 2 data for DISC-0974 in myelofibrosis anemia and progress on DISC-3405, coupled with a strong cash position providing runway into 2029, offer some mitigation. Investors will closely monitor the APOLLO study results and subsequent FDA interactions for bitopertin, as well as further data from the other pipeline programs.