Bristol Myers Squibb’s mavacamten did not significantly improve functional capacity or symptoms in patients with nonobstructive hypertrophic cardiomyopathy, missing primary endpoints in a phase III trial, the company reported.

Mavacamten was evaluated in adults with symptomatic nonobstructive hypertrophic cardiomyopathy (nHCM), an inherited cardiomyopathy characterized by myocardial hypertrophy without left ventricular outflow tract obstruction.

Hypertrophic cardiomyopathy affects approximately 1 in 500 adults globally and is the most common identifiable cause of sudden cardiac death in young individuals in the United States.

Camzyos (mavacamten) is already approved in the United States for obstructive HCM.

“The trial failure reflects the difficulty of demonstrating clinical benefit in less severe populations,” said BMO Capital Markets analyst Evan Seigerman, adding that it increases pressure on upcoming data readouts.

No new safety signals were identified.

Camzyos carries a boxed warning for the risk of heart failure.

The 580-participant trial assessed health status using a patient-reported outcome measure, including symptom burden and functional limitations.

Mavacamten also did not improve peak oxygen consumption after 48 weeks.

The company plans to present full data at a future scientific meeting.