Disc Medicine (IRON) investor relations material

Key program updates and regulatory milestones

• Lead program bitopertin targets porphyria (EPP), with phase III APOLLO data expected by Q4 and potential resubmission by year-end, aiming for mid-2025 approval.

• Accelerated approval pathway was not granted; a Complete Response Letter (CRL) redirected the program to a standard phase III path, but the regulatory path is considered straightforward.

• Type A FDA meeting will confirm alignment on trial design, with co-primary endpoints of PPIX reduction and time in light.

• Enrollment for APOLLO completed ahead of schedule, with high demand and broad geographic participation.

• Commercial launch preparations were scaled back, with layoffs, but a core team remains to build physician engagement and market readiness.

Clinical data highlights and trial design

• Phase II data for bitopertin showed significant reduction in protoporphyrin IX and strong efficacy on several endpoints, though one key endpoint (time in light) was not statistically significant.

• Placebo effect influenced phase II results; phase III design now focuses on the final month of time in light to mitigate this.

• APOLLO is powered at over 80% for the primary endpoint, with sample size recalculation confirming assumptions.

• Bitopertin’s mechanism targets the root cause of EPP, differentiating it from competitors that focus on symptom management.

Pipeline progress and future outlook

• DISC-0974, an antibody for anemia in myelofibrosis, showed promising phase II results, with broad efficacy across patient subgroups and compatibility with JAK inhibitors.

• Full phase II data for DISC-0974 expected by year-end, with plans for an End-of-Phase II FDA meeting to define pivotal trial design.

• Phase II program in IBD anemia is underway, with initial data expected next year, focusing on hepcidin, iron, and hemoglobin markers.

• DISC-3405 in polycythemia vera doubled its cohort size due to high enthusiasm; initial data expected later this year, supporting a potential pivotal trial in 2027.

• The portfolio is positioned for multiple data readouts and regulatory milestones across rare and hematologic diseases through 2025-2027.