A phase 3 randomized trial has identified aficamten as a promising potential treatment for people with symptomatic nonobstructive hypertrophic cardiomyopathy, an inherited condition in which the heart muscle becomes abnormally thick and everyday exertion can become difficult.
Results reported on August 28, 2026, in the New England Journal of Medicine and presented at the European Society of Cardiology Congress involved 517 participants treated across 160 health centers in 19 countries. Nearly half received aficamten, while the remainder received placebo during the controlled phase of the trial.
The study was led internationally by researchers including Ahmad Masri of Oregon Health & Science University. Aficamten is a cardiac myosin inhibitor designed to reduce excessive contraction and help the heart muscle relax. OHSU said the trial produced improvements in symptoms and physical function for patients whose condition has historically had limited drug-treatment options.
Nonobstructive hypertrophic cardiomyopathy does not block blood flow in the same way as the obstructive form, but it can still cause chest pain, breathlessness, fatigue and reduced exercise tolerance. The condition is usually inherited, and OHSU estimates that hypertrophic cardiomyopathy affects about one in 350 people worldwide, with roughly half experiencing the nonobstructive form.
Researchers and clinicians cautioned that the findings do not mean aficamten is already approved for this specific use. The trial was funded by Cytokinetics, the drug’s developer, and OHSU disclosed research and consulting relationships involving the company.
The next major step is regulatory review. If the results are confirmed and approval is granted, aficamten could expand treatment options for patients whose symptoms remain disabling despite current management. Until then, patients should not change heart medication or exercise plans without guidance from their cardiologist.
