Trial results for Aficamten in adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) were posted on ClinicalTrials.gov on 2026-03-03. The Phase 3 study showed that Aficamten treatment led to a 1.74 mL/kg/min greater improvement in peak oxygen uptake (pVO2) at Week 24 compared to placebo, with a p-value of 0.0001.
Background
Obstructive Hypertrophic Cardiomyopathy (oHCM) is a condition characterized by thickening of the heart muscle, which can obstruct blood flow from the left ventricle. Aficamten (CK-3773274) is an investigational drug being evaluated for its efficacy and safety in adults with symptomatic oHCM.
Trial design
The study (NCT05186818) was a Phase 3, randomized, placebo-controlled trial designed to evaluate Aficamten in adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM). The trial enrolled 282 participants, who received either Aficamten (at doses of 5 mg, 10 mg, 15 mg, or 20 mg) or a matching placebo.
Key results
The trial demonstrated significant improvements across several key efficacy measures for Aficamten compared to placebo:
- Peak Oxygen Uptake (pVO2) at Week 24: Aficamten treatment resulted in a least squares mean change from baseline of 1.76 mL/kg/min (Standard Error: 0.25) versus 0.02 mL/kg/min (Standard Error: 0.25) for placebo. The mean difference between groups was 1.74 mL/kg/min (95.0% CI: 1.04 to 2.44), with a p-value of 0.0001.
- Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS) at Week 24: Aficamten showed a least squares mean change from baseline of 11.6 score on a scale (Standard Error: 1.0) compared to 4.3 score on a scale (Standard Error: 1.0) for placebo. The least squares mean difference was 7.3 (95.0% CI: 4.6 to 10.1), with a p-value of 0.0001. At Week 12, the difference was 7.0 (95.0% CI: 4.5 to 9.5), p-value 0.0001.
- NYHA Functional Class Improvement: At Week 24, 83 participants on Aficamten achieved at least a 1-class improvement versus 34 on placebo, with a rate difference of 34.2 (95.0% CI: 23.4 to 45.0), p-value 0.0001. At Week 12, the Odds Ratio was 4.4 (95.0% CI: 2.6 to 7.6), p-value 0.0001.
- Valsalva Left Ventricular Outflow Tract Gradient (LVOT-G) at Week 24: Aficamten led to a least squares mean change from baseline of -48 mmHg (Standard Error: 2.4), while placebo showed a change of 2 mmHg (Standard Error: 2.4).
What this means
The results of this Phase 3 trial indicate that Aficamten significantly improved objective measures of exercise capacity (pVO2) and patient-reported symptoms (KCCQ-CSS, NYHA functional class) in adults with symptomatic obstructive hypertrophic cardiomyopathy. The substantial reduction in Valsalva Left Ventricular Outflow Tract Gradient further supports the drug's potential to address the underlying obstruction in oHCM. These findings suggest Aficamten could offer a meaningful therapeutic option for managing oHCM symptoms and improving quality of life.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT05186818, titled "Phase 3 Trial to Evaluate the Efficacy and Safety of Aficamten Compared to Placebo in Adults With Symptomatic oHCM," were posted on 2026-03-03 on clinicaltrials.gov.