Effect of beta‐blocker therapy on the response to mavacamten in patients with symptomatic obstructive hypertrophic cardiomyopathy

In the EXPLORER-HCM trial, mavacamten improved exercise capacity and symptoms in patients with obstructive hypertrophic cardiomyopathy (oHCM). Mavacamten effects on the primary endpoint, a composite of peak oxygen consumption (VOSubgroup analyses by beta-blocker use were performed in patients with oHCM from the EXPLORER-HCM and mavacamten long-term extension (MAVA-LTE) studies. In EXPLORER-HCM, 189 patients (75.3%) were receiving beta-blockers, and 62 (24.7%) were receiving non-dihydropyridine calcium-channel blockers or no background HCM medication; 170 patients (90.4%) receiving beta-blockers had chronotropic incompetence. Improvements in peak VOMavacamten improved measures of functional capacity, LVOT obstruction, symptom burden and biomarkers in patients with HCM regardless of beta-blocker use. Beta-blocker use was often associated with chronotropic incompetence, affecting peak VO