What it isAn investigational first-in-class cardiac myosin activator that increases the number of active actin-myosin cross-bridges, enhancing myocardial contractility without raising intracellular calcium or myocardial oxygen demand.
Why this oneStudied in heart failure with reduced ejection fraction (GALACTIC-HF), where it modestly reduced heart-failure events but is not FDA-approved.
What limits itIt received an FDA complete response letter in 2023; excessive exposure prolongs systolic ejection time and can precipitate myocardial ischemia, and it is a CYP3A substrate.
NO BOXED WARNINGS
Principal riskNo FDA boxed warning (investigational, not approved).
