Cytokinetics reports ACACIA-HCM trial met both primary endpoints

Cytokinetics (CYTK) announced topline results from ACACIA-HCM, the pivotal Phase 3 clinical trial of aficamten in patients with symptomatic non-obstructive hypertrophic cardiomyopathy. ACACIA-HCM met both dual primary endpoints, demonstrating statistically significant improvements from baseline to Week 36 compared to placebo in both Kansas City Cardiomyopathy Questionnaire Clinical Summary Score and maximal exercise performance. The improvement in KCCQ was robust and consistent throughout the treatment period in participants on aficamten. Following washout, KCCQ decreased for participants on aficamten to match the placebo group. At Week 36, pVO2 increased for participants on aficamten, while it remained unchanged for participants on placebo, consistent with prior trials of aficamten in obstructive HCM. Statistically significant improvements compared to placebo were observed in key secondary endpoints including the proportion of participants with improvements in New York Heart Association Functional Class, the composite z-score of ventilatory efficiency and pVO2, and NT-proBNP. There were no new safety signals identified. The percentage of participants completing planned dosing was similar in those receiving aficamten or placebo. Left ventricular ejection fraction less than 50% occurred in 27 participants taking aficamten and in two participants taking placebo. Two participants on aficamten experienced a serious adverse event of heart failure associated with LVEF less than 50%. Treatment interruptions due to LVEF less than40% occurred in 3% of participants taking aficamten.