Disc Medicine Presents Positive Initial Data from RALLY-MF Phase 2 Trial in Patients with Myelofibrosis (MF) and Anemia at the 67th American Society of Hematology (ASH) Annual Meeting

• Demonstrated meaningful overall anemia responses across all patient subgroups, regardless of baseline transfusion status 
• Anemia response was seen independent of concomitant JAK inhibitor therapy use

WATERTOWN, Mass., Dec. 06, 2025 (GLOBE NEWSWIRE) -- Disc Medicine, Inc. (NASDAQ:IRON), a clinical-stage biopharmaceutical company focused on the discovery, development, and commercialization of novel treatments for patients suffering from serious hematologic diseases, today presented positive initial data from the RALLY-MF Phase 2 trial of DISC-0974 in anemia of MF at the ASH Annual Meeting in Orlando, FL. The data demonstrated that treatment with DISC-0974 resulted in substantial reductions in hepcidin and increases in iron levels translating to positive impact on clinically meaningful measures of anemia across a broad range of patient types.

“We are excited that we continue to see robust hematologic responses to DISC-0974 regardless of background JAK inhibitor therapy,” said John Quisel, J.D., Ph.D., President and Chief Executive Officer of Disc Medicine. “It is also encouraging to see these hematologic improvements translating into reduced transfusion burden and fatigue. We look forward to advancing this program with the goal of addressing a significant unmet need as anemia is one of the key manifestations of MF and there is currently no therapy approved to treat anemia in this population.”

This ongoing Phase 2 open-label study had enrolled 47 adult patients with MF and anemia as of the data cutoff date of October 16, including 34 patients with sufficient follow up to be included in the responder analysis (non-transfusion dependent receiving no transfusions (nTD, n=24), transfusion dependent with low transfusion burden (TD Low, n=7) and transfusion dependent with high transfusion burden (TD High, n=3)). The trial was comprised of both patients receiving concomitant JAK inhibitor therapy (n=18) and not receiving JAK inhibitor therapy (n=16). DISC-0974 was administered subcutaneously at 50 mg every 4 weeks for up to 6 treatments. Initial results demonstrated:

• Consistent, substantial decreases in hepcidin reaching >75% reduction from baseline and corresponding increases in serum iron
• 63% of baseline nTD patients achieved a hemoglobin increase of ≥1 g/dL for ≥12 weeks (overall response) and 50% had an increase of ≥1.5 g/dL for ≥12 weeks (major response)
• 71% of TD Low patients achieved transfusion independence (TI, major response) over a 16-week period
• 67% of TD High patients with at least 85 days on study achieved a ≥50% reduction in transfusion requirement (overall response)
  • Initial data for additional n=3 TD High patients trending towards major response of TI >12 weeks
• 50% of patients receiving concomitant JAK inhibitor therapy achieved a major hematologic response
• Dosing with DISC-0974 was associated with improvements in FACIT-Fatigue scores in nTD and TD Low participants
• DISC-0974 was generally well-tolerated. Diarrhea and urinary tract infections, neither considered serious, were the only adverse events (AE) that were considered related to DISC-0974 and reported in two or more subjects. The majority of AEs were not considered related to DISC-0974.
• Additional data to be shared in H2 2026
  

Disc also shared a poster overviewing the trial design for the ongoing Phase 2 study of the anti-TMPRSS6 antibody DISC-3405 in polycythemia vera requiring frequent phlebotomy.

Management will host a call during the ASH meeting to review highlights of the presented data and plans for next steps in development on Sunday, December 7 at 7:30am EST. Please register for the event on the Events and Presentations page of Disc’s website (https://ir.discmedicine.com/).

About Disc Medicine

Disc Medicine (NASDAQ:IRON) is a clinical-stage biopharmaceutical company committed to discovering, developing, and commercializing novel treatments for patients who suffer from serious hematologic diseases. We are building a portfolio of innovative, potentially first-in-class therapeutic candidates that aim to address a wide spectrum of hematologic diseases by targeting fundamental biological pathways of red blood cell biology, specifically heme biosynthesis and iron homeostasis. For more information, please visit www.discmedicine.com.

Disc Cautionary Statement Regarding Forward-Looking Statements

This press release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding Disc’s expectations with respect to its RALLY-MF Phase 2 clinical trial of DISC-0974 in patients with MF and anemia, including the results thereof and the projected timeline for the presentation of additional data. The use of words such as, but not limited to, “believe,” “expect,” “estimate,” “project,” “intend,” “future,” “potential,” “continue,” “may,” “might,” “plan,” “will,” “should,” “seek,” “anticipate,” or “could” or the negative of these terms and other similar words or expressions that are intended to identify forward-looking statements. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on Disc’s current beliefs, expectations and assumptions regarding the future of Disc’s business, future plans and strategies, clinical results and other future conditions. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.

Disc may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and investors should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements as a result of a number of material risks and uncertainties including but not limited to: the adequacy of Disc’s capital to support its future operations and its ability to successfully initiate and complete clinical trials; the nature, strategy and focus of Disc; the difficulty in predicting the time and cost of development of Disc’s product candidates; Disc’s plans to research, develop and commercialize its current and future product candidates; the timing of initiation of Disc’s planned preclinical studies and clinical trials; the timing of the availability of data from Disc’s clinical trials; Disc’s ability to identify additional product candidates with significant commercial potential and to expand its pipeline in hematological diseases; the timing and anticipated results of Disc’s preclinical studies and clinical trials and the risk that the results of Disc’s preclinical studies and clinical trials may not be predictive of future results in connection with future studies or clinical trials and may not support further development and marketing approval; and the other risks and uncertainties described in Disc’s filings with the Securities and Exchange Commission, including in the “Risk Factors” section of Disc’s Annual Report on Form 10-K for the year ended December 31, 2024, and in subsequent Quarterly Reports on Form 10-Q. Any forward-looking statement speaks only as of the date on which it was made. None of Disc, nor its affiliates, advisors or representatives, undertake any obligation to publicly update or revise any forward-looking statement, whether as result of new information, future events or otherwise, except as required by law.

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