WARRINGTON, Pa.—Windtree Therapeutics, Inc., a biotechnology and medical device company focused on developing drug product candidates and medical device technologies to address acute cardiovascular and pulmonary diseases, announced today that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation for istaroxime for the treatment of acute heart failure.
“We are very pleased to receive FDA’s Fast Track designation for istaroxime. This Fast Track designation for istaroxime underscores the significant unmet medical need to treat patients suffering from acute heart failure and the potential of istaroxime as demonstrated by the Phase 2 clinical results,” said Craig Fraser, president and chief executive officer. “Istaroxime is a novel, dual-action agent that impacts both the systolic and diastolic function of the heart in patients hospitalized with acute heart failure.”
Istaroxime is a first-in-class, dual action, luso-inotropic agent in clinical development for the treatment of acute heart failure with reduced ejection fraction. Istaroxime is an intravenously-administered agent with a positive inotropic agent that increases myocardial contractility through inhibition of Na+/K+-ATPase. In addition, it facilitates myocardial relaxation through activation of the SERCA2a calcium pump on the sarcoplasmic reticulum enhancing calcium reuptake from the cytoplasm.
“In recently announced results from a Phase 2b study evaluating istaroxime in acute heart failure patients, we achieved our primary objective of improved cardiac function, while maintaining or increasing blood pressure and decreasing heart rate during the infusion,” Fraser added. “Additionally, we observed a well characterized safety profile for istaroxime. We look forward to continuing our work with the FDA and the cardiology community to advance istaroxime through clinical development and the regulatory approval process, with the goal of bringing to market a transformative therapy to treat acute heart failure patients.”
Windtree Therapeutics presented new safety and efficacy data from their Phase 2b study of istaroxime in patients hospitalized with acute heart failure (AHF) at a late-breaking session of the European Society of Cardiology (ESC) 2019 Heart Failure Congress in May.
The study achieved its primary endpoint by demonstrating a significant improvement (p<0.05) in cardiac function at both istaroxime study doses. The study also showed that stroke volume, a key secondary endpoint, was substantially increased. Certain toxicities and complications experienced with many existing acute heart failure therapies were not observed in istaroxime-treated patients, including no signals of increased arrhythmias or increased troponin levels, a common marker of heart muscle damage. Istaroxime significantly increased or maintained systolic blood pressure during treatment, which may have contributed to a short-term trend toward improvement in renal function.
“We are very encouraged by the results from this Phase 2b study evaluating istaroxime, our novel, dual action agent that addresses both cardiac contractility and relaxation in patients with acute heart failure. We achieved our primary objective of improved cardiac function, while maintaining or increasing blood pressure and decreasing heart rate during the infusion,” noted Steve Simonson, M.D., chief medical officer at Windtree, in a press release. “We also did not observe other important safety signals in the patients studied. These positive results are consistent with the physiologic improvements seen in the Phase 2a study in a similar population of patients with acute heart failure. Based on these promising results, we look forward to progressing the development of istaroxime.”