No therapy is currently approved for patients with symptomatic nonobstructive hypertrophic cardiomyopathy (nHCM). An exploratory analysis from the ODYSSEY-HCM trial, published in the Journal of the American College of Cardiology, examined baseline biomarker associations and longitudinal changes with mavacamten treatment in this population.

The randomized trial enrolled 580 adults with symptomatic nHCM who received mavacamten or placebo for 48 weeks. Mavacamten was initiated at 5 mg per day, with dose titration guided by left ventricular ejection fraction. Biomarker assessments included NT-proBNP and hs-cTnI, measured at baseline and through week 48 alongside clinical and echocardiographic parameters.

At baseline, median NT-proBNP was 917.5 ng/L, and median hs-cTnI was 29.1 ng/L. Higher NT-proBNP levels were associated with female sex, body mass index, New York Heart Association functional class, maximal left ventricular wall thickness, left atrial volume index, and E/e’. Higher hs-cTnI levels were associated with younger age and left ventricular mass index.

At week 48, the mavacamten group demonstrated a 58% reduction in NT-proBNP (geometric mean ratio 0.42; 95% confidence interval 0.37 to 0.47; P < 0.001) and a 51% reduction in hs-cTnI (geometric mean ratio 0.49; 95% confidence interval 0.45 to 0.53; P < 0.001). No significant changes were observed in the placebo group. Biomarker reductions occurred early and were sustained through week 48.