Windtree has a total of 59 issued or allowed patents and 17 pending patents for Istaroxime and its SERCA2a activators

Windtree received recent notification of allowed Istaroxime patents

for acute heart failure in Canada and Mexico

The pure SERCA2a activators patent for acute heart failure was granted in Isreal

WARRINGTON, Pa., Nov. 14, 2025 (GLOBE NEWSWIRE) -- Windtree Therapeutics, Inc. ("Windtree" or "the Company") (OTCID: WINT), a diversified company with several divisions and focused on becoming a revenue generating company, announced that acute heart failure patents are allowed in Canada (Patent Application No. 3,130,261) and Mexico (Patent Application No. MX/a/2021/010483). Additionally, the next generation pure SERCA2a activator patent for heart failure was granted in Isreal (Patent Application No. 291412).

This latest news for Windtree's cardiovascular pipeline makes a total of 58 patents issued or allowed, with 17 pending. The cardiovascular patent estate includes istaroxime, the dual mechanism SERCA2a activators and the pure SERCA2a activators for the treatment of heart failure, prevention of arrhythmias and treatment of cardiogenic shock.

Heart failure affects 60 million people globally of which approximately 20 million are admitted annually due to Acute HF, 1.5 million in the US. In patients with systolic blood pressure BP < 120 mmHg, in-hospital and 6-month mortality can reach double digit percentages. Additionally, hospital readmission after discharge and/or worsening heart failure and/or death are areas that need drug innovation.

Current treatment options for acute heart failure patients are limited and can have side effects such as arrythmias and problems with renal function.

"We are very pleased to be strengthening our cardiovascular patent estate," said Jed Latkin, Chief Executive Officer of Windtree. "We believe that istaroxime has a unique profile to effectively treat acute heart failure patients with low blood pressure, who are most in need. Further, istaroxime has demonstrated favorable results in renal function and no increase in arrythmias that is lacking with currently available drugs. We are pursuing partnership for development and believe that the clinical studies to date are very encouraging in considering a Phase 3 program for istaroxime."

About Windtree Therapeutics, Inc.

Windtree Therapeutics, Inc. is a diversified company with several divisions and focused on becoming a revenue generating company with future profitability.

About Istaroxime

Istaroxime is a first-in-class dual-mechanism therapy designed to improve both systolic and diastolic cardiac function. Istaroxime is a positive inotropic agent that increases myocardial contractility through inhibition of Na+/K+- ATPase with a complimentary mechanism that facilitates myocardial relaxation through activation of the SERCA2a calcium pump on the sarcoplasmic reticulum enhancing calcium reuptake from the cytoplasm. Data from multiple Phase 2 studies in patients with early cardiogenic shock or acute decompensated heart failure demonstrate that istaroxime infused intravenously can significantly improve cardiac function and blood pressure without increasing heart rate or the incidence of clinically significant cardiac rhythm disturbances.

About Pure SERCA2a Activators

These compounds activate SERCA2a and Windtree Therapeutic's research and development program is evaluating these preclinical product candidates, including oral and intravenous SERCA2a activator heart failure compounds.

Forward Looking Statements

The Company may, in some cases, use terms such as "predicts," "believes," "potential," "proposed," "continue," "estimates," "anticipates," "expects," "plans," "intends," "may," "could," "might," "will," "should," or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. Such statements are based on information available to the Company as of the date of this press release and are subject to numerous important factors, risks, and uncertainties that may cause actual events or results to differ materially from the Company's current expectations. Examples of such risks and uncertainties include, among other things: risks related to the Company's ability to begin its environmental services business, and manage costs and execute on its operational and budget plans. These and other risks are described in the Company's periodic reports, including its Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, filed with or furnished to the Securities and Exchange Commission and available at www.sec.gov. Any forward-looking statements that the Company makes in this press release speak only as of the date of this press release. The Company assumes no obligation to update forward-looking statements whether as a result of new information, future events, or otherwise, after the date of this press release.

Contact Information:

Eric Curtis

ecurtis@windtreetx.com

Windtree Therapeutics Announces More Strengthening of Its Istaroxime and Next Generation SERCA2a activator Patent Estate