Mavacamten monotherapy in obstructive hypertrophic cardiomyopathy: An integrated analysis of phase 3 clinical trials.

BACKGROUND

Mavacamten was associated with improvements in symptoms and cardiac function in patients with obstructive hypertrophic cardiomyopathy (HCM) across multiple phase 3 studies. Most patients in these studies received mavacamten with background HCM pharmacological therapies. This study assessed mavacamten monotherapy efficacy and safety in an integrated analysis of 4 phase 3 studies.

METHODS

Patients from EXPLORER-HCM, the EXPLORER cohort of MAVA-LTE, VALOR-HCM and EXPLORER-CN were pooled and divided by background therapy use at the time of mavacamten initiation: mavacamten monotherapy, mavacamten plus beta-blockers or mavacamten plus calcium-channel blockers.

RESULTS

Mavacamten monotherapy was associated with improvements in left ventricular outflow tract gradients and symptoms in patients with obstructive hypertrophic cardiomyopathy; descriptive comparisons with patients receiving mavacamten plus beta-blockers or calcium-channel blockers suggested broadly similar trends in efficacy and adverse event rates. Reductions in left ventricular ejection fraction from baseline to week 128 of ≤8.8% were observed across treatment groups.

CONCLUSIONS

In patients with symptomatic obstructive HCM, mavacamten monotherapy was associated with improvements in clinical and echocardiographic outcomes, with a similar safety profile to that observed with mavacamten plus background HCM therapy in clinical trials.

TRIAL REGISTRATION: EXPLORER-HCM, NCT03470545; MAVA-LTE, NCT03723655; VALOR-HCM, NCT04349072; and EXPLORER-CN, NCT05174416.