Windtree Therapeutics, Inc. (NASDAQ:WINT) has commenced patient enrollment in its SEISMiC-C trial, a Phase 2 study evaluating istaroxime in patients with SCAI Stage C cardiogenic shock. This follows positive data from earlier SEISMiC A and B studies in SCAI Stage B cardiogenic shock, which demonstrated that istaroxime improved systolic blood pressure, cardiac function, and renal function without increasing the risk of cardiac arrhythmias.
SEISMiC-C Trial Design
The SEISMiC-C trial is a global, placebo-controlled, double-blind study. It will assess the effect of istaroxime, added to standard of care inotropes or vasopressors, over a six-hour period. The primary endpoint is the assessment of systolic blood pressure (SBP) profile during the initial six hours of treatment. Secondary endpoints include measures of cardiac function, SBP changes at specified time points, vasopressor-inotrope score, avoidance of progression to SCAI Stage D or E cardiogenic shock, need for mechanical cardiac support, time to treatment failure, arrhythmia assessments, days alive and out of the hospital through day 30, physiologic measures (e.g., cardiac index), and length of stay in the ICU and hospital.
Istaroxime: A Novel Approach to Cardiogenic Shock
Istaroxime is a first-in-class investigational therapy designed to improve both systolic contraction and diastolic relaxation of the heart. It simultaneously boosts blood pressure and maintains renal function. The dual mechanism of action impacts both systolic and diastolic dysfunction. By inhibiting the sodium-potassium ATPase, istaroxime creates a stronger contraction. By stimulating SERCA2a activity, istaroxime also aids the heart in relaxing between contractions, allowing it to fill with blood more effectively.
Unmet Need in Cardiogenic Shock
Cardiogenic shock is a severe condition with limited effective therapies. It is characterized by reduced cardiac output, organ hypoperfusion, and hypoxia. Current treatments often involve inotropic or vasopressor drugs, which can have harmful side effects. Windtree believes istaroxime can potentially avoid these side effects.
Patent Expansion and Licensing
Windtree has been issued several patents for istaroxime, including recent patents for Hong Kong, Japan and mainland China. Lee’s Pharmaceutical, Windtree’s licensing partner, intends to launch a Phase 3 program in acute heart failure for its Greater China territory, which Lee is funding. This agreement could yield up to $138 million in potential milestone and royalty payments for Windtree.
Anticipated Milestones
A data review is planned after enrollment of approximately 20 participants with SCAI Stage C cardiogenic shock due to acute decompensated heart failure, expected in late Q1/early Q2 2025. Windtree anticipates that the SEISMiC-C trial data will highlight the potential advantages of istaroxime compared to current standard of care therapies. The company expects to interact with regulators in 2025 to transition to a Phase 3 clinical trial.
