Camzyos shows sustained benefit through 56 weeks in paediatric obstructive HCM

Bristol Myers Squibb has reported 56-week Phase III results from the SCOUT-HCM trial showing sustained efficacy and a consistent safety profile for Camzyos in adolescents with symptomatic obstructive hypertrophic cardiomyopathy.

The study evaluated mavacamten in patients aged 12 to under 18 years and provides longer-term follow-up beyond the previously reported 28-week placebo-controlled period.

SCOUT-HCM enrolled 44 patients, of whom 43 completed the double-blind phase and entered the active treatment period.

During the first 28 weeks, participants received either Camzyos or placebo.

All patients who completed this phase then received Camzyos through week 56.

Patients who were treated with mavacamten throughout the study achieved a mean reduction in Valsalva left ventricular outflow tract gradient of 48.1 mmHg from baseline after 56 weeks.

Patients who initially received placebo also experienced a similar degree of LVOT gradient reduction after switching to mavacamten.

Both treatment groups showed improvements across several secondary endpoints.

No new safety signals were identified during the extended follow-up period.

Bristol Myers Squibb also reported that no patient experienced a left ventricular ejection fraction below 50% during the 56-week evaluation.

Treatment-related treatment-emergent adverse events remained uncommon.

Five treatment-related adverse events and two serious treatment-related adverse events were reported in patients who received mavacamten for the full 56 weeks.

Among patients who switched from placebo to mavacamten, one treatment-related adverse event and no serious treatment-related adverse events were reported during their 28 weeks of active treatment.

Cordula Wolf, MD, Associate Professor at the Technical University of Munich University Hospital German Heart Centre, said the findings extend understanding of Camzyos in paediatric patients by providing 56 weeks of follow-up after a controlled Phase III study.

The results build on the earlier 28-week SCOUT-HCM findings that supported U.S. approval of Camzyos for paediatric patients weighing at least 30 kg with symptomatic obstructive hypertrophic cardiomyopathy.

The FDA approved the treatment for this population in September 2026.

Camzyos was previously approved in 2022 for adults with symptomatic New York Heart Association class II to III obstructive hypertrophic cardiomyopathy.

Bristol Myers Squibb is also presenting additional Camzyos data at the American Heart Association Scientific Sessions 2026.

These include longer-term findings from the Camzyos Risk Evaluation and Mitigation Strategy programme, cardiac imaging analyses from MAVA-LTE, cardiovascular risk biomarker findings from EXPLORER-HCM and real-world data from MARVEL-HCM.

The additional analyses are intended to further assess the long-term efficacy and safety of mavacamten across different patient populations with symptomatic obstructive hypertrophic cardiomyopathy.

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Related Topics and Keywords

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