Hot Line 2: MAPLE-HCM
31 Aug 2025
Hot Line ESC Congress 2025 Aficamten in obstructive hypertrophic cardiomyopathy: MAPLE-HCM
Doctor Pablo Garcia-Pavia (Hospital Universitario Puerta de Hierro Majadahonda and Centro Nacional de Investigaciones Cardiovasculares (CNIC) - Madrid, Spain) presented results from the international phase III MAPLE-HCM trial, which compared aficamten with metoprolol, both as monotherapy, in patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM).
In total, 175 adults with symptomatic obstructive HCM were randomised to aficamten (uptitrated from 5 to 20 mg as tolerated) or metoprolol (uptitrated from 50 to 200 mg as tolerated). Eligible patients had NYHA class II or III symptoms, a Kansas City Cardiomyopathy Questionnaire–Clinical Summary Score (KCCQ-CSS) ≤90 and age- and sex-predicted peak oxygen uptake <100%. The primary endpoint was change in peak oxygen uptake at 24 weeks.
Peak oxygen uptake increased by 1.1 ml/kg/min with aficamten and decreased by 1.2 ml/kg/min with metoprolol, resulting in a significant difference in favour of aficamten (p<0.001).
The effect of aficamten on exercise capacity appeared consistent across all prespecified subgroups, including newly diagnosed or treatment-naïve patients (30% of the total).
At 24 weeks, aficamten was associated with symptom and health status improvements compared with metoprolol: the proportion of patients who had ≥1 class improvement in NYHA class was 51.1% vs. 26.4%, respectively, and the least-squares mean changes in KCCQ-CSS were 15.8 and 8.7 points, respectively. Serious adverse events occurred in 8.0% of participants with aficamten and 6.9% with metoprolol.
Concluding, Dr. Garcia-Pavia said: “By directly comparing aficamten and metoprolol, the MAPLE-HCM trial expands our understanding of how aficamten may be optimally integrated into the management of patients with obstructive HCM. Here we show that aficamten – as monotherapy and as first-line therapy – demonstrated greater improvements in exercise capacity and symptoms than beta-blockers.”
