Danicamtiv (MYK-491) is a cardiac myosin inhibitor developed to treat hypertrophic cardiomyopathy (HCM), particularly obstructive HCM. It works by directly reducing the excessive activity of cardiac myosin, the motor protein driving heart muscle contraction, which helps improve diastolic relaxation, reduce left ventricular outflow tract obstruction, and alleviate symptoms such as shortness of breath and chest pain.

By selectively modulating sarcomere function, danicamtiv normalizes hypercontractility in HCM without significantly increasing heart rate or oxygen demand, distinguishing it from conventional therapies like beta-blockers or calcium channel blockers that primarily slow heart rate or reduce afterload.

This targeted approach addresses the underlying genetic defects causing excessive contractility in HCM, a condition affecting heart muscle thickening and function. Danicamtiv has been evaluated in clinical trials, including the phase 2 PIONEER-HCM study, demonstrating improvements in exercise capacity, symptoms, and hemodynamics in patients with obstructive HCM.

As a first-in-class myosin modulator, it offers a novel sarcomere-directed treatment option, potentially reducing the need for invasive procedures like septal myectomy in eligible patients.