Iron given through a vein for heart failure with iron deficiency

Trial details

Who runs it

Government of Jersey

Trial code

NCT07643818

Record updated

24 August 2026

Original description

This study will investigate whether intravenous (IV) iron improves symptoms, exercise capacity, and quality of life in patients with heart failure with preserved ejection fraction (HFpEF) and iron deficiency.Read full original descriptionShow less

Intravenous Iron to Improve Symptoms, Quality of Life and Exercise Capacity in HFpEF With Iron Deficiency

This study will investigate whether intravenous (IV) iron improves symptoms, exercise capacity, and quality of life in patients with heart failure with preserved ejection fraction (HFpEF) and iron deficiency.

Iron deficiency is common in heart failure and is associated with worse symptoms, reduced physical activity, poorer quality of life, and increased hospitalisation risk. Intravenous iron therapy has demonstrated clinical benefit in patients with heart failure with reduced ejection fraction (HFrEF), but evidence in HFpEF remains limited.

ISLE-HFpEF is a prospective, randomised, double-blind, placebo-controlled trial enrolling 150 adults with symptomatic HFpEF and iron deficiency. Participants will be randomised in a 1:1 ratio to receive either intravenous ferric derisomaltose (Monofer) or placebo (0.9% sodium chloride). Participants will undergo baseline assessment, treatment infusion, and 12-week follow-up.

The primary outcome is change in 6-minute walk distance at 12 weeks. Secondary outcomes include change in Kansas City Cardiomyopathy Questionnaire (KCCQ) score, physical activity measured using wearable accelerometers, transferrin saturation, NT-proBNP, and New York Heart Association (NYHA) functional class.

The study will also evaluate the feasibility and utility of continuous digital monitoring using wearable technologies, including a thigh-worn SENS Motion accelerometer and the Oura Ring, to assess real-world physical activity and cardiovascular physiology throughout the study period.

Inclusion: Age ≥18 years; Willing and able to provide written informed consent; Clinical diagnosis of heart failure with ejection fraction ≥40%; New York Heart Association (NYHA) class II or III symptoms at the time of randomisation; Ambulatory for at least 7 days prior to randomisation; Iron deficiency defined as transferrin saturation (TSAT) <20% or serum iron ≤13umol/L; Haemoglobin ≤15.0 g/dL; Baseline 6-minute walk distance <450 metres.

Exclusion: Intravenous iron therapy, erythropoietin therapy, or blood transfusion within the previous 3 months; Concurrent immunosuppressive therapy; Severe COPD defined as FEV1 <50%, requirement for home oxygen therapy, or chronic oral steroid therapy; Concurrent therapy with an erythropoiesis-stimulating agent; Clinical signs or symptoms of active infection, including fever >38°C; Known iron overload syndrome or haemochromatosis, or first-degree relative with haemochromatosis; Known hypersensitivity to ferric derisomaltose (Monofer) or other intravenous iron preparations; Known bleeding anaemia or haemolytic anaemia; Any condition precluding exercise testing, including decompensated heart failure, unstable angina, obstructive cardiomyopathy, severe uncorrected valvular disease, significant musculoskeletal disease, or uncontrolled bradyarrhythmias or tachyarrhythmias; Probable alternative explanation for symptoms in the opinion of the investigator, including severe obesity, primary pulmonary hypertension, or chronic obstructive pulmonary disease (COPD); Uncontrolled atrial fibrillation with resting heart rate >110 beats/minute; Uncontrolled hypertension with blood pressure >180/110 mmHg; Known active malignancy; Known HIV infection or active hepatitis infection; Decompensated liver disease; Prior documented left ventricular ejection fraction (LVEF) <40%; Renal replacement therapy or estimated glomerular filtration rate (eGFR) <15 mL/min/1.73m²; Unable or unwilling to provide informed consent; Pregnancy.

ClinicalTrials.gov NCT07643818