EMERGING ROLE OF MAVACAMTEN IN PRECISION MEDICINE FOR HYPERTROPHIC CARDIOMYOPATHY

Mavacamten is a first-in-class, orally administered, selective allosteric inhibitor of beta-cardiac myosin ATPase. Its novel mechanism directly targets the core pathophysiology by reducing the formation of actin-myosin cross-bridges, shifting myosin heads towards a relaxed, energy-sparing state. This action decreases myocardial contractility and alleviates LVOT obstruction in an exposure-dependent manner. Hypertrophic cardiomyopathy (HCM), a prevalent genetic myocardial disorder, is characterized by hypercontractility which often leads to dynamic left ventricular outflow tract (LVOT) obstruction in the obstructive phenotype (oHCM). Traditional pharmacotherapies, such as beta-blockers and calcium channel blockers, offer symptomatic relief but are non-specific and often inadequate. Critically, the VALOR-HCM trial demonstrated that mavacamten substantially reduced the proportion of patients eligible for septal reduction therapy (SRT), positioning it as a potent non-invasive alternative. Mavacamten is extensively metabolized primarily by the polymorphic CYP2C19 enzyme, resulting in a highly variable half-life (6–9 days in normal metabolizers, approximately 23 days in poor metabolizers). Mavacamten represents a paradigm shift from symptomatic management to a disease-specific approach for oHCM. While long-term data and strategies for managing its complex pharmacogenetics continue to evolve, it establishes a foundational advance in the medical management of this condition.