FDA Approves Bumetanide Nasal Spray for Edema with Congestive Heart Failure

The US Food and Drug Administration (FDA) has approved bumetanide nasal spray (Enbumyst) for the treatment of edema associated with congestive heart failure (CHF), liver disease, and chronic kidney disease (CKD).1

Announced by Corstasis Therapeutics on September 15, 2025, the FDA’s decision is in response to the unmet need in edema and fluid overload, which are the main causes of hospitalization and readmission for patients with CHF, cirrhosis, and CKD.1

Loop diuretics are the first-line treatment for congestion, used to control volume status in patients with heart failure (HF). Most patients admitted to the hospital for HF are given intravenous (IV) loop diuretics irrespective of perfusion status. This is because the high plasma content in loop diuretics is needed to cross the threshold to rapid and effective diuresis. However, chronic use of loop diuretics can lead to a blunted response in acute decompensated HF, which is attributed to functional and structural tubular remodeling.2

Bumetanide nasal spray is an intranasal loop diuretic designed for absorption through the nasal application. Developed to circumvent the absorption block presented by an overreliance on intravenous loop diuretics in managing diuresis, bumetanide nasal spray saw its star begin to rise with positive results from the RSQ-777-02 trial. It was conducted from December 2023 to April 2024 and included 68 adults, ages 18 to 55 years, without HF or risk of HF before enrollment.3

"[Bumetanide nasal spray] was designed in direct collaboration with cardiologists to address practical challenges in the outpatient care setting," Brian Kolski, MD, chief medical director of Corstasis and director, non-invasive vascular lab at the Orange County Heart Institute and director of structural heart disease at Providence St. Joseph Hospital in Orange, California, said in a statement.1

During the study, investigators gave patients all 3 forms of bumetanide – nasal, oral, and intravenous – in a varied order. The nasal spray was safe and well-tolerated throughout, with no significant nasal irritation observed. The team also noted an absorption variability of 27% in the nasal and IV forms of bumetanide, while the oral, pill form had a variability of >40%. Additionally, BNS had fewer treatment-emergent adverse events than the oral version.3

Ultimately, bumetanide nasal spray met its primary endpoint of equivalence to oral bumetanide, and no significant difference in maximum plasma concentration was noted between the treatments. Additionally, a higher time to maximum concentration was observed in bumetanide nasal spray versus the oral tablets, indicating earlier detection of peak plasma drug concentrations after the nasal application.2

Corstasis Therapeutics presented the results at the American Heart Association Scientific Sessions in 2024 and submitted the New Drug Application for BNS shortly afterwards. The FDA accepted the application in January of 2025.4

"[Bumetanide nasal spray] offers the potential to change the standard of care by enabling earlier, outpatient intervention," Anuradha Lala-Trindade, MD, director of heart failure research at the Mount Sinai Fuster Hospital in New York, said in a statement. "This innovation may meaningfully improve outcomes while potentially easing the economic burden on the healthcare system."1

According to the press release, Corstasis expects to launch bumetanide nasal spray in the US during the fourth quarter of 2025.1

References

1. Corstasis Therapeutics. Corstasis Therapeutics Announces FDA Approval of ENBUMYST (bumetanide nasal spray) for the Treatment of Edema Associated with Congestive Heart Failure, Liver Disease, and Kidney Disease. BusinessWire. September 15, 2025. Accessed September 15, 2025. https://www.businesswire.com/news/home/20250915243998/en/Corstasis-Therapeutics-Announces-FDA-Approval-of-ENBUMYST-bumetanide-nasal-spray-for-the-Treatment-of-Edema-Associated-with-Congestive-Heart-Failure-Liver-Disease-and-Kidney-Disease

2. Biegus J, Ponikowska B, Canonico ME, Damman K, Palazzuoli A, Ambrosy AP. Bumetanide nasal spray: a novel approach to enhancing diuretic response and advancing ambulatory heart failure care?. Heart Fail Rev. 2025;30(5):1123-1126. doi:10.1007/s10741-025-10517-y

3. American College of Cardiology. RSQ-777-02: New Nasal Spray Form of Bumetanide as Effective as Oral and IV Forms in Patients Without HF or HF Risk. November 18, 2024. Accessed September 11, 2025. https://www.acc.org/latest-in-cardiology/articles/2024/11/13/21/17/mon-930am-rsq77702-aha-2024

4. Iapoce C. FDA Accepts New Drug Application for Bumetanide Nasal Spray. HCPLive. January 27, 2025. Accessed September 11, 2025. https://www.hcplive.com/view/fda-accepts-new-drug-application-for-bumetanide-nasal-spray