Compared with placebo, mavacamten (Mava), a novel inhibitor of cardiac myosin, for 30 weeks leads to improvement in left ventricular (LV) hypertrophy and markers of left-sided filling pressures in patients with obstructive hypertrophic cardiomyopathy (oHCM), according to a study presented at the American Heart Association Scientific Sessions 2020, held virtually from Nov. 13 to 17.
Sheila M. Hegde, M.D., M.P.H., from Brigham and Women's Hospital in Boston, and colleagues examined the effect of Mava on focused measures of cardiac structure and function in oHCM in a double-blind, placebo-controlled phase 3 trial. Symptomatic oHCM patients were randomly assigned to either Mava or placebo for 30 weeks in a 1:1 ratio; 244 patients completed the study.
The researchers found that 30-week treatment with Mava led to significant reductions in left arterial volume index, lateral E/e', septal E/e'. and LV mass index compared with placebo. Significantly more patients treated with Mava than placebo achieved resolution of mitral valve systolic anterior motion and mitral regurgitation (80.9 versus 34.0 percent and 9.0 versus 0.0 percent, respectively).
"These findings reinforced and extended data from prior open label trials. Additional changes in measures of cardiac structure and function were also observed, including reduction in the size of the left atrium," Hedge said in a statement. "Together, these results reflect this medication's impact on the underlying pathophysiology of hypertrophic cardiomyopathy. A long-term extension trial is ongoing and will provide additional insight on the long-term impact on cardiac structure and function."
Several authors disclosed financial ties to pharmaceutical companies, including MyoKardia, which is developing mavacamten and funded the study.
