SUBCUT HF II: rationale and design of a multicentre randomized controlled trial of SUBCUTaneous furosemide to support early discharge in patients admitted to hospital due to Heart Failure

INTRODUCTION: Heart failure (HF) hospitalizations are frequent and lengthy, and usually involve treatment with intravenous diuretics to relieve congestion. SUBCUT HF II is evaluating the safety and efficacy of an alternative ambulatory care strategy using a novel subcutaneous formulation of furosemide delivered via a wearable pump. METHODS: The SUBCUT HF II trial is a multicentre, randomized, active comparator trial involving 20 hospitals in the UK. Eligible participants are patients with HF receiving inpatient treatment with intravenous loop diuretic. Patients are randomized to either early supported discharge, using a novel formulation of subcutaneous furosemide (SQIN-Furosemide) administered by a wearable pump (SQIN-Infusor), or continued inpatient treatment using intravenous furosemide. RESULTS: The primary endpoint is days spent alive and out of hospital at 30 days. As of October 2025, 168 of 170 patients have been randomized. CONCLUSION: The SUBCUT HF II trial is testing the safety and efficacy of an ambulatory care approach to managing patients presenting to the hospital with HF. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT05419115.