Cytokinetics reports positive late-stage data for heart drug aficamten

Aug 28, 2026

Cytokinetics reported positive late-stage trial data for its heart drug aficamten, showing significant improvements in symptoms and exercise capacity for patients with non-obstructive hypertrophic cardiomyopathy (nHCM). The company plans to submit a supplemental U.S. marketing application in late 2026. While the drug did not improve heart structure and caused some adverse heart failure events, analysts forecast over $5 billion in peak sales for the drug, marketed as Myqorzo.

Aficamten late-stage trial results

▪The late-stage trial of aficamten did not significantly improve heart structure or delay cardiovascular events in patients with non-obstructive hypertrophic cardiomyopathy
▪In a 517-patient study, 53% of patients taking Cytokinetics' drug aficamten showed meaningful improvements in at least three of five key disease areas, compared to 13% on a placebo
▪Detailed late-stage trial data showed that Cytokinetics' drug aficamten significantly improved symptoms and exercise capacity in patients with non-obstructive hypertrophic cardiomyopathy

Myqorzo label expansion to nHCM

▪Cytokinetics' drug aficamten is already approved under the brand name Myqorzo for obstructive hypertrophic cardiomyopathy, which causes thickened heart muscles to block blood flow
▪Cytokinetics plans to submit a supplemental marketing application for aficamten to the U.S. Food and Drug Administration in the fourth quarter of 2026 to expand its use to non-obstructive hypertrophic cardiomyopathy

Heart failure adverse events

▪Cytokinetics Chief Medical Officer Steve Heitner stated that an early imbalance of heart failure events in the study was caused by a rigid trial dosing algorithm that removed clinical judgment
▪During the late-stage study of aficamten, approximately 10% of patients experienced a dangerous drop in their heart's pumping capacity, and 12 heart failure events occurred

Bristol Myers Camzyos competition

▪Barclays analysts expect Cytokinetics will hold the non-obstructive hypertrophic cardiomyopathy market to itself for a multi-year period before facing direct competition
▪Bristol Myers plans to start a late-stage study of its rival drug, Camzyos, in patients with non-obstructive hypertrophic cardiomyopathy later in 2026

Peak sales forecasts

▪Barclays analysts forecast over $5 billion in peak sales for Cytokinetics' drug Myqorzo
▪Barclays analysts expect that holding the non-obstructive hypertrophic cardiomyopathy market will trigger a halo effect that boosts Cytokinetics' existing sales for obstructive hypertrophic cardiomyopathy

Ulacamten HFpEF development

▪B. Riley analysts noted that the aficamten trial data will act as a vital bridge to validate Cytokinetics' next-generation drug, ulacamten, in heart failure with preserved ejection fraction
▪Heart failure with preserved ejection fraction is a condition in which heart muscles stiffen and draw in less blood, representing a multi-billion dollar treatment market where Cytokinetics will compete against Bristol Myers