Cytokinetics, Incorporated (Nasdaq: CYTK) presented additional data from its ACACIA-HCM clinical trial at the Heart Failure Society of America Annual Scientific Meeting 2026 in Phoenix, Arizona, according to a company press release.

The data covered three areas: comprehensive exercise performance, a global efficacy responder analysis, and dose titration and safety. In the exercise performance analysis, treatment with aficamten significantly improved scores on the Boston Exercise Aggregate Physiologic Response Score at 36 weeks compared to placebo (p<0.001), with gains across all five measured domains. Score improvements correlated with health status measures and the cardiac biomarker NT-proBNP.

In the responder analysis, 53% of patients on aficamten demonstrated a clinical response in three or more of five assessed domains, compared to 13% on placebo (p<0.001). Statistically significant improvements were seen in four of the five domains, including relief of limiting symptoms and a reduction in NT-proBNP of at least 50%.

On dosing and safety, 80.7% of patients reached doses of 15 or 20 mg by the end of the titration period. Left ventricular ejection fraction below 50% occurred in 10.5% of patients on aficamten versus 0.8% on placebo. Serious adverse events of heart failure were reported in 12 patients (4.7%) on aficamten compared to three patients (1.2%) on placebo. All heart failure events in the aficamten group occurred during dose titration or before week 12, and responded to standard medical therapy.

Cytokinetics said it plans to submit a supplemental New Drug Application to the U.S. Food and Drug Administration for aficamten in non-obstructive hypertrophic cardiomyopathy in the fourth quarter of 2026. Aficamten is currently approved in the U.S., China, European Union, and United Kingdom under the brand name Myqorzo for symptomatic obstructive hypertrophic cardiomyopathy.