Cytokinetics Presents New MYQORZO Data at Heart Failure Congress

Cytokinetics announced the presentation of new data reinforcing the clinical profile of MYQORZO at the European Society of Cardiology Heart Failure 2026 Congress. The presentations include new analyses from SEQUOIA-HCM, the pivotal Phase 3 clinical trial of aficamten in patients with oHCM; MAPLE-HCM, the Phase 3 clinical trial of aficamten compared to metoprolol in patients with symptomatic obstructive HCM; and FOREST-HCM, the open-label extension trial of aficamten. A dose-dependent analysis from MAPLE-HCM compared aficamten to the beta-blocker metoprolol in patients with symptomatic oHCM. Key findings showed significant improvements in exercise capacity, outflow gradients, and N-terminal pro-B-type natriuretic peptide across all treatment doses. Conversely, metoprolol failed to show improvement in these outcomes regardless of the dose administered. A secondary analysis of sex differences in MAPLE-HCM showed consistent benefits of MYQORZO in women. Despite women entering the trial with more severe baseline characteristics, MYQORZO delivered nearly identical improvements in peak oxygen consumption for both sexes. Both groups also saw significant gains in Kansas City Cardiomyopathy Questionnaire Clinical Summary Score and reductions in cardiac biomarkers and NT-proBNP. A prospective analysis of 122 patients who had interpretable ambulatory electrocardiogram data at screening in the FOREST-HCM showed that long-term treatment with MYQORZO-up to 96 weeks-did not increase the incidence of arrhythmias in patients, including those who underwent withdrawal of beta-blocker therapy. Among 122 patients, the incidence of non-sustained ventricular tachycardia on ambulatory ECG remained stable through 96 weeks compared with baseline, with no increase in atrial fibrillation episodes and no newly identified subclinical AF. There was also no increase in arrhythmia frequency among a subgroup of 16 patients who discontinued beta-blocker therapy during aficamten treatment. These results represent the first prospective analysis of ambulatory ECG monitoring in patients treated with a cardiac myosin inhibitor and are consistent with the low incidence of clinically detected arrhythmias previously reported for patients with oHCM treated with aficamten. Additionally, an open-label extension study of aficamten in Chinese patients with symptomatic oHCM showed that aficamten was well tolerated using the same dosing strategy of individualized titration as was used globally.