FDA approved Camzyos (mavacamten) for the treatment of symptomatic obstructive hypertrophic cardiomyopathy (oHCM) to improve functional capacity and symptoms in adults and pediatric patients weighing 30 kg (66 lbs) or more.

The approval gives Camzyos the broadest indication of any cardiac myosin inhibitor (CMI) on the market, extending a therapy first cleared for adults in 2022 down to adolescent patients for the first time and addresses a population that has historically had no FDA-approved, disease-targeted therapy.¹

"Today's approval of Camzyos for pediatric patients with symptomatic obstructive hypertrophic cardiomyopathy marks an important milestone for young patients and families who are facing a serious cardiovascular disease with significant unmet medical need," said Al Reba, senior vice president, immunology & cardiovascular commercialization, Bristol Myers Squibb. "For young patients living with this disease, the burden on daily life can be substantial during a critical stage of development, and we are proud to help bring an innovative new treatment option to this community."

What did the Scout-HCM trial show?

The approval is based on the Phase III Scout-HCM trial, a randomized, double-blind, placebo-controlled, international study that enrolled 44 adolescent patients ages 12 to younger than 18 with symptomatic NYHA (New York Heart Association) Class II-III oHCM.² Patients were randomized 1:1 to receive Camzyos or placebo once daily for 28 weeks, with dosing based on body weight and adjusted according to echocardiogram parameters.² Enrolled patients left ventricular ejection fraction (LVEF) of at least 60%, a Valsalva left ventricular outflow tract (LVOT) peak gradient of at least 30 mmHg, and a maximal gradient of at least 50 mmHg at rest or with provocation.²

Camzyos met the trial's primary endpoint, producing a statistically significant reduction in Valsalva LVOT gradient at week 28 compared with placebo, with a mean change of -49.4 mmHg versus -1.8 mmHg, a least-squares mean difference of -48.0 mmHg.² Secondary endpoints also favored Camzyos, including a resting LVOT gradient difference of -47.0 mmHg, a postexercise LVOT gradient difference of -41.7 mmHg, and a maximal left ventricular wall thickness difference of -1.8 mm versus placebo.²

No patients in the trial experienced LVEF below 50%, and no adverse events led to treatment discontinuation.² Serious adverse events occurred in two patients each in the Camzyos (9%) and placebo (10%) groups, and no new adverse reactions emerged beyond the safety profile already observed in adults.

Joseph Rossano, MD, principal investigator of Scout-HCM and chief of the division of cardiology at Children's Hospital of Philadelphia, called it "a landmark moment for pediatric cardiology," noting that "for the first time, children with this serious condition have a therapy that is FDA-approved to reduce left ventricular outflow tract obstruction."

Lisa Salberg, CEO and founder of the Hypertrophic Cardiomyopathy Association, framed the approval in personal terms. "I cannot help but think back to my 12-year-old self receiving my diagnosis and being told there were no treatment options approved specifically for my disease," she said. "This is truly a milestone moment for patients and families."

Beyond the U.S., the pediatric data from Scout-HCM is now being discussed with multiple global regulatory authorities as Bristol Myers Squibb pursues additional pediatric indications.

Sources

1. U.S. Food and Drug Administration Approves Expanded Indication for Bristol Myers Squibb’s CAMZYOS® (mavacamten) for the Treatment of Symptomatic Obstructive Hypertrophic Cardiomyopathy (oHCM) in Adults and Pediatric Patients* Bristol Myers Squibb September 30, 2026, https://news.bms.com/news/details/2026/U-S--Food-and-Drug-Administration-Approves-Expanded-Indication-for-Bristol-Myers-Squibbs-CAMZYOS-mavacamten-for-the-Treatment-of-Symptomatic-Obstructive-Hypertrophic-Cardiomyopathy-oHCM-in-Adults-and-Pediatric-Patients/default.aspx
2. A Study to Evaluate Mavacamten in Adolescents With Symptomatic Obstructive Hypertrophic Cardiomyopathy National Library of Medicine December 19, 2025, https://clinicaltrials.gov/study/NCT06253221