Patients randomized to treatment at home spent an average of four (4) fewer days in the hospital compared to those treated with standard-of-care intravenous (IV) furosemide, according to the trial's results, presented May 9 at Heart Failure 2026, the annual congress of the Heart Failure Association (HFA) of the European Society of Cardiology (ESC), in Barcelona, Spain.
SUBCUT HF II is a multicenter, open-label, randomized controlled trial conducted across 20 National Health Service (NHS) hospitals in the U.K. The trial was co-sponsored by the University of Glasgow and the National Health Service (U.K.) Greater Glasgow and Clyde Health Board and led by Principal Investigators Dr. Ross T. Campbell and Professor Mark C. Petrie of the Glasgow Cardiovascular Research Centre, University of Glasgow.
"Edema in heart failure is a leading reason for hospital admissions worldwide," said Professor Petrie. "This novel treatment option relies on the same therapeutic fundamentals that have been in place in the hospital since the 1960s, and enabling this to now be done at home by a patient or caregiver fundamentally changes the nature and trajectory of this very common and burdensome disorder."
The trial evaluated at-home treatment of heart failure patients as an alternative to standard hospital treatment. For the study, 172 patients with heart failure were enrolled shortly after they were admitted to a hospital for treatment of edema or fluid overload. Ninety-two patients were randomized to receive at-home treatment with Lasix ONYU and 80 received in-hospital treatment with IV diuretics.
Patients randomized in the study had a mean age of 71 years and were representative of a typical hospitalized heart failure population requiring diuretic therapy, with a median NT-proBNP of 3,365 pg/mL, peripheral edema present in 92%, and pleural effusion in 29%.
The primary endpoint was an avoidance of a minimum of 3.5 days of inpatient care also referred to as Days Alive and Out of Hospital (DAOH) over the 30-day period starting with the moment of randomization. The primary endpoint reflects that the at-home therapy was effective and safe with low readmission due to treatment failure or admission for complications.
Secondary endpoints included:
- Length of index hospitalization,
- Change in health status at 60 days (assessed by the KCCQ-12),
- Days spent alive and out of hospital from randomization to 60 days
- Total number of HF hospitalizations at 60 days
- CV death or first HF hospitalization at 60 days
- CV death at 60 days
- Safety as determined by treatment emergent adverse events (TEAEs)
- Device failures
The researchers reported length of index hospitalization reduced by 5.5 days (p<0.001), and benefits of DAOH remained at 60 days (4.23 DAOH difference between groups – p<0.001).
Secondary endpoints supported that aside from the avoidance of inpatient days, at-home Lasix ONYU treatment was equivalent to in-hospital treatment.
Patients in the at-home treatment arm received a full therapeutic dose by self- administration of approximately 11 units on average (880 mg). This total dose for an episode of edema in heart failure is consistent with published literature for in-hospital treatment.
Adverse events were infrequent, and no device-related serious adverse event occurred. Lasix ONYU treatment was generally well tolerated.
"The SUBCUT HF II study represents an important milestone on this path home for the many patients for whom this is an option," said Pieter Muntendam, MD founder, President and CEO of SQ Innovation, the manufacturer of Lasix ONYU. "This is the first outcomes study of home use of subcutaneous furosemide that meets the goals of demonstrating hospital avoidance and safe home use."
Edema (fluid overload) is a leading cause of hospitalizations globally for people over 65 years old with heart failure, and typically requires inpatient IV diuretic therapy that could take up to one week. In the U.S., over 1.2 million people are admitted for heart failure each year, significantly contributing to Medicare and other health insurance expenses amid ongoing hospital overcrowding.
Lasix ONYU is a novel drug-device combination that was approved by the U.S. Food and Drug Administration (FDA) in October 2025, for the treatment of edema in adult patients with chronic heart failure. The Lasix ONYU Infusor slowly administers 80 mg of the diuretic furosemide over a period of five hours, resulting in significant diuresis similar to IV, but in a controlled manner designed for at-home administration to minimize risk of orthostatic hypotension and falls.
About SUBCUT HF II
SUBCUT HF II (ClinicalTrials.gov: NCT05419115) is a multicenter, prospective, open-label, parallel-group, active comparator, phase II randomized controlled trial evaluating the safety and efficacy of an early supported discharge strategy using a novel subcutaneous formulation of furosemide in patients hospitalized due to heart failure.
About SQ Innovation
SQ Innovation, Inc. is a privately held Swiss biopharmaceutical company with offices in Zug, Switzerland, Burlington, MA, USA, and Rotterdam, The Netherlands. The company was founded to develop and commercialize innovative, cost-effective therapies for subcutaneous delivery, enabling at-home treatment for conditions that are usually managed during hospitalizations. SQ Innovation has developed a novel drug-device combination for treating edema in adult patients with chronic heart failure — a condition typically requiring intravenous administration of diuretics in a hospital setting. Lasix ONYU was developed with consideration for patients, payors, healthcare providers, and environmental impact. Lasix ONYU received approval from the U.S. Food and Drug Administration on October 7, 2025.
About Lasix ONYU
Lasix® ONYU is a drug-device combination that was approved by the U.S. Food and Drug Administration on October 7, 2025, for the treatment of edema in adult patients with chronic heart failure. Lasix ONYU is available for ordering from Cardinal and Cencora and for dispensing and overnight delivery from Walmart Specialty Pharmacy. The pharmaceutical component of Lasix ONYU is a novel, high-concentration formulation of the diuretic furosemide, at 30 mg/mL. It comes in a pre-filled glass cartridge containing 80 mg of furosemide in 2.67 mL. The Lasix ONYU Infusor consists of two main parts: the Reusable Unit and the Disposable Unit. The Reusable Unit is an electromechanical device that contains the battery, motor, and electronic components necessary for operation and safety functions. It can be used up to 48 times before it can be recycled. The Disposable Unit is a sterile, single-use plastic component that holds the drug cartridge. It includes a micro-`piston pump, fluid path, needle insertion and retraction mechanism, and a 29-gauge needle. After placement on the abdomen, the needle penetrates the skin when the device is activated. The Lasix ONYU Infusor slowly administers 80 mg furosemide over a period of five hours. This method results in significant diuresis similar to IV, but in a more controlled manner. This avoids the brief, intense diuretic effect that occurs with rapid IV infusion or injection. Lasix ONYU is a second-generation combination product for subcutaneous furosemide that follows the introduction of Furoscix in 2023. The advanced two component design of Lasix ONYU offers benefits for patients, healthcare providers, payers, and the environment.
