New study shows that treatment with MonoFerric® (ferric derisomaltose) improves exercise capacity in patients with heart failure with preserved ejection fraction and iron deficiency
-- Press Release – Morristown, New Jersey - November 8, 2026
Pharmacosmos A/S today announced that results from the IRONMET-HFpEF study have been published in Circulation. The randomized, double-blind, placebo-controlled study found that MonoFerric® (ferric derisomaltose) improved exercise capacity over 12 weeks compared with placebo in patients with heart failure with preserved ejection fraction (HFpEF) and iron deficiency.
Iron deficiency affects 50% of people with heart failure and is associated with reduced exercise capacity and poorer quality of life [1]. Heart failure affects approximately 1–2% of adults in developed countries, with prevalence increasing markedly with age [2].
IRONMET-HFpEF focused on patients with iron deficiency and HFpEF (~50% of all HF patients [3]), a form of heart failure in which the heart pumps out a normal proportion of blood with each beat but can have difficulty relaxing and filling between beats, resulting in fluid congestion. Patients commonly experience breathlessness and difficulty with physical activity, including everyday tasks such as walking or climbing stairs [4].
The IRONMET-HFpEF study, sponsored by the National Institutes of Health and conducted at Massachusetts General Hospital in Boston, investigated whether correcting iron deficiency with MonoFerric, an intravenous iron treatment developed and manufactured by Pharmacosmos, could improve exercise capacity in these patients. It enrolled 65 patients at a single center and compared MonoFerric with placebo over 12 weeks. The main measure was peak oxygen uptake, the highest amount of oxygen the body uses during an exercise test. Peak oxygen uptake is a key measure of heart failure disease burden that objectively captures the burden of functional limitation experienced by people with HFpEF.
At 12 weeks, the adjusted difference between groups in the change in peak oxygen uptake was 1.1 mL/kg/min in favor of MonoFerric (95% confidence interval [CI], 0.2 to 1.9; P=0.02). Patients receiving MonoFerric also showed a greater improvement in the distance walked in six minutes, with a between-group difference of 41.1 meters (95% CI, 9.5 to 72.8; P=0.01).
“In the first study to comprehensively evaluate exercise response patterns to iron repletion in patients with HFpEF and iron deficiency, we found that MonoFerric improved multiple measures of exercise capacity,” said the principal investigator Gregory Lewis, MD, Director of Heart Failure, Mass General Brigham Heart and Vascular Institute and Professor of Medicine, Harvard Medical School.
Few studies have examined intravenous iron in HFpEF. IRONMET-HFpEF represents a step towards understanding whether correcting iron deficiency can improve exercise capacity in this less studied patient group.
“The improvement we observed in peak VO2 represents a clinically meaningful increment for patients with heart failure,” said co-principal investigator Rajeev Malhotra, MD, Associate Director of the Cardiopulmonary Exercise Laboratory at the Mass General Brigham Heart and Vascular Institute and Associate Professor of Medicine at Harvard Medical School.
Research into iron deficiency across different heart failure populations includes Pharmacosmos’ support for IRONMAN [5] and its ongoing international Phase III trial, ICONIC-HF, involving clinical sites across Europe, Latin America, Asia, Canada and the United States.
MonoFerric is not approved to improve exercise capacity in patients with heart failure with preserved ejection fraction and iron deficiency.
About the study
IRONMET-HFpEF is an investigator-initiated, National Heart, Lung, and Blood Institute-sponsored, randomized, double-blind, placebo-controlled trial conducted at Massachusetts General Hospital in Boston. Sixty-five adults with HFpEF and iron deficiency were randomized 2:1 to receive a single 1,000 mg intravenous dose of MonoFerric or placebo. The primary endpoint was change in peak oxygen uptake from baseline to week 12. The study included participants with and without anemia and was registered at ClinicalTrials.gov (NCT04945707). The results were presented November 8 in a Late-breaking Science Session at the American Heart Association Scientific Sessions 2026 in Chicago and published simultaneously in Circulation.
Scan QR code or click here for access to the publication.
The findings are limited by the sample size of 65 patients, single-center design and 12-week follow-up. Kansas City Cardiomyopathy Questionnaire (KCCQ) did not differ significantly between groups, and the study was not designed to assess longer-term outcomes such as hospitalization or mortality. In this study, no serious adverse events were related to MonoFerric.
Pharmacosmos donated the study drug.
About MonoFerric® (ferric derisomaltose)
MonoFerric is indicated for the treatment of iron deficiency anemia (IDA) in adult patients:
who have intolerance to oral iron or have had unsatisfactory response to oral iron
who have non-hemodialysis-dependent chronic kidney disease (NDD-CKD)
Important Safety Information
CONTRAINDICATIONS
MonoFerric is contraindicated in patients with a history of serious hypersensitivity to MonoFerric or any of its components. Reactions have included shock, clinically significant hypotension, loss of consciousness, and/or collapse.
WARNINGS AND PRECAUTIONS
Hypersensitivity Reactions
Serious hypersensitivity reactions, including anaphylactic-type reactions, some of which have been life-threatening and fatal, have been reported in patients receiving MonoFerric. Patients may present with shock, clinically significant hypotension, loss of consciousness, and/or collapse. Monitor patients for signs and symptoms of hypersensitivity during and after MonoFerric administration for at least 30 minutes and until clinically stable following completion of the infusion. Only administer MonoFerric when personnel and therapies are immediately available for the treatment of serious hypersensitivity reactions. MonoFerric is contraindicated in patients with prior serious hypersensitivity reactions to MonoFerric or any of its components. In clinical trials in patients with IDA and CKD, serious or severe hypersensitivity was reported in 0.3% (6/2008) of the MonoFerric treated subjects. These included 3 events of hypersensitivity in 3 patients, 2 events of infusion-related reactions in 2 patients, and 1 event of asthma in 1 patient.
Iron Overload
Excessive therapy with parenteral iron can lead to excess iron storage and possibly iatrogenic hemosiderosis or hemochromatosis. Monitor the hematologic response (hemoglobin and hematocrit) and iron parameters (serum ferritin and transferrin saturation) during parenteral iron therapy. Do not administer MonoFerric to patients with iron overload.
ADVERSE REACTIONS
Adverse reactions were reported in 8.6% (172/2008) of patients treated with MonoFerric. Adverse reactions related to treatment and reported by ≥1% of the treated patients were nausea (1.2%) and rash (1%). Adjudicated serious or severe hypersensitivity reactions were reported in 6/2008 (0.3%) patients in the MonoFerric group. Hypophosphatemia (serum phosphate <2.0 mg/dL) was reported in 3.5% of MonoFerric-treated patients in Trials 1 and 2.
To report adverse events, please contact Pharmacosmos at 1-888-828-0655. You may also contact the FDA at www.fda.gov/medwatch or call 1-800-FDA-1088.
Please see full Prescribing Information.
About Pharmacosmos
We are a family-owned company innovating in iron metabolism, blood disorders, and cell cycle biology. With 700+ employees globally, we prioritize quality, collaboration, and patient care to drive life-changing treatments.
Contact
Cory Steinberg, Executive Director, Marketing Supportive Care
610.608.5953 | [email protected]
Lewis G, et al. Circulation 2026, DOI: 10.1161/CIRCULATIONAHA.126.084009.
Khan MS, et al. Nat Rev Cardiol. 2024 for overall HF epidemiology.
Campbell P, Rutten FH, Lee MMY, Hawkins NM, Petrie MC. Heart failure with preserved ejection fraction: everything the clinician needs to know. The Lancet. 2024;403:1083–1092.
Ejection Fraction Heart Failure Measurement | American Heart Association. Accessed 11/26.
Kalra PR et al., The Lancet. 2022;400:2199–2209.
Contact Info:
Name: Cory Steinberg
Email: Send Email
Organization: Pharmacosmos Therapeutics, Inc.
Phone: 610.608.5953
Website: https://pharmacosmos.us/
Release ID: 89208867
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