In an interim analysis of 465 patients with symptomatic obstructive hypertrophic cardiomyopathy who received mavacamten, researchers reported statistically significant improvements in echocardiographic markers of diastolic function and cardiac remodeling at 18 months. The retrospective analysis did not include a comparator group, and the abstract did not report endpoint-specific 18-month follow-up denominators.
Mavacamten is a selective cardiac-specific myosin inhibitor approved in more than 50 countries for adults with symptomatic obstructive hypertrophic cardiomyopathy. According to the study authors, prior randomized studies showed improvements in diastolic function and markers of cardiac remodeling in obstructive hypertrophic cardiomyopathy patients treated with mavacamten.
MARVEL-HCM is described as an ongoing retrospective study of patient-level data across 8 sites in the US. The interim analysis covered patients treated from April 29, 2022, to August 6, 2024. According to the abstract, all patients received mavacamten in accordance with the US Prescribing Information.
Researchers assessed medial and lateral e′ velocities, average E/e′ ratio, left ventricular wall thickness (LVWT), left ventricular mass index (LVMI), and left atrial volume index (LAVI) at baseline and at 18 months.
Cohort characteristics. The cohort had a mean age of 64.8 years, and 54.6% of patients were female, per the abstract's Results text. Baseline characteristics reported in the accompanying table included an NYHA class distribution of 49.5% class II and 50.3% class III, mean left ventricular ejection fraction of 68.3%, and resting and Valsalva left ventricular outflow tract gradients of 49.3 mmHg and 84.1 mmHg, respectively.
Diastolic function. At 18 months, the study authors reported a statistically significant increase in medial e′ velocity (0.05 m/s to 0.06 m/s) and lateral e′ velocity (0.07 m/s to 0.08 m/s), along with a statistically significant decrease in average E/e′ ratio (17.4 to 14.2).
Cardiac remodeling. The study authors also reported statistically significant decreases in LVWT (18.5 mm to 17.6 mm), LVMI (126.3 g/m² to 117.6 g/m²), and LAVI (45.5 mL/m² to 38.4 mL/m²).
Safety. Researchers reported no new safety signals. The abstract did not provide event rates, treatment discontinuation rates, dose-adjustment data, or LVEF-related safety outcomes — details that would be needed to more fully interpret the safety findings reported in the abstract.
Limitations. This was a retrospective, uncontrolled analysis without a reported comparator group, statistical adjustment methods, missing-data handling, or per-endpoint counts of patients with complete 18-month echocardiographic data. As a result, the findings describe longitudinal change among treated patients but do not establish how much of that change is attributable to mavacamten as opposed to patient selection, concurrent clinical management, or availability of follow-up data.
Study Presentation: PRESIDENT'S CIRCLE 2, American Society of Echocardiography Annual Scientific Sessions
Disclosures: Formal conflict-of-interest disclosures were not included in the supplied abstract text. Two listed authors (Ervant J. Maksabedian Hernandez and Michael S. Emery) are affiliated with Bristol Myers Squibb per their listed institutional affiliation in the abstract byline.
