IRON

Business Context and Reporting Period

Company: Disc Medicine, Inc. (Nasdaq: IRON)
Filing Type: Form 10-K (Annual Report)
Reporting Period: Fiscal year ended December 31, 2025
Business Overview: Disc Medicine is a clinical-stage biopharmaceutical company focused on hematologic diseases. Its pipeline targets heme biosynthesis (bitopertin for EPP/XLP) and iron homeostasis (DISC-0974 for anemia of myelofibrosis/IBD; DISC-3405 for polycythemia vera/sickle cell disease). The company has no products approved for commercial sale and has not generated product revenue.

Key Financial Metrics

Note: All figures in millions unless otherwise noted.

Material Changes vs. Prior Period

• Net Loss Increase: Net loss more than doubled to $212.2 million in 2025 from $109.4 million in 2024, driven by a $106.3 million increase in operating expenses.
• R&D Expense Surge: R&D expenses increased by $74.0 million (76% increase). Key drivers included:
  • Bitopertin: $30.7 million increase due to a $10.0 million milestone payment for initiating the APOLLO Phase 3 trial and increased costs for the APOLLO and HELIOS trials.
  • DISC-0974: $10.6 million increase due to clinical trial advancement.
  • DISC-3405: $3.8 million increase driven by a $10.0 million milestone payment for Phase 2 initiation.
  • Personnel Costs: $19.6 million increase in R&D personnel costs, including a $9.0 million rise in stock-based compensation.
• SG&A Expense Surge: SG&A expenses increased by $32.3 million (98% increase), primarily due to a $17.5 million increase in personnel costs (including $8.6 million in stock-based compensation) and a $13.1 million increase in legal and professional fees related to commercialization preparations.
• Liquidity Position: Cash and marketable securities increased by $301.3 million to $791.2 million, bolstered by $454.4 million in net proceeds from equity offerings in 2025.

Guidance, Outlook, and Material Events

• Regulatory Setback (Bitopertin): In February 2026, the FDA issued a Complete Response Letter (CRL) regarding the NDA for accelerated approval of bitopertin for EPP/XLP. While the FDA agreed bitopertin lowers PPIX, it concluded the trials did not demonstrate an association between PPIX reduction and sunlight exposure endpoints. The FDA indicated that results from the ongoing Phase 3 APOLLO trial could support a potential traditional approval.
• Clinical Trial Outlook:
  • APOLLO (Bitopertin): Topline data expected in Q4 2026. The company plans to submit a response to the CRL following these results.
  • RALLY-MF (DISC-0974): Initial Phase 2 data reported in December 2025 showed meaningful anemia responses. Topline data expected in H2 2026.
  • RESTORE-PV (DISC-3405): Initial data expected in H2 2026.
• Capital Resources: Management believes current cash, cash equivalents, and marketable securities ($791.2 million) are sufficient to fund operations and debt service obligations into 2029.
• Debt Obligations: The company has a $200.0 million senior secured term loan facility with Hercules Capital. As of year-end, $30.0 million was drawn. The loan matures in December 2029 and includes a minimum cash covenant effective January 1, 2027 (waived if market cap exceeds $1.0 billion).
• Risk Factors: Significant risks include the uncertainty of regulatory approval for bitopertin, the need for substantial additional funding if capital is exhausted sooner than expected, and reliance on third-party manufacturers and CROs.

Key Facts for Investor Verification

• Regulatory Path Forward: Verify the specific requirements outlined in the FDA's February 2026 CRL for bitopertin and the company's strategy to address the lack of association between PPIX reduction and clinical benefit.
• Cash Burn Rate: Monitor the quarterly cash burn rate against the stated runway into 2029, particularly given the significant increase in operating expenses in 2025.
• APOLLO Trial Enrollment: Track enrollment progress and interim data timelines for the APOLLO Phase 3 trial, which is critical for the potential traditional approval of bitopertin.
• Milestone Payments: Review upcoming contingent milestone payments under license agreements with Roche, AbbVie, and Mabwell, which could impact future cash flows.
• Debt Covenants: Confirm compliance with the minimum cash covenant under the Hercules Loan Agreement, which becomes effective in 2027 unless the market cap threshold is met.