- Question
- Can the oral myosin inhibitor mavacamten enable patients with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) to no longer meet guideline criteria for septal reduction therapy, or to choose not to undergo it?
- Design
- Phase 3, randomized, double-blind, placebo-controlled trial of 112 patients with 16 weeks of treatment. The dose was titrated according to the left ventricular outflow tract (LVOT) gradient and ejection fraction.
- Population
- Adults with symptomatic oHCM, an LVOT gradient ≥50 mm Hg at rest or with provocation, and guideline criteria for septal reduction therapy (surgical myectomy or alcohol septal ablation). Mean age was 60 years, 93% were in NYHA functional class III/IV, and the mean post-exercise LVOT gradient was 84 mm Hg.
- Intervention
- Mavacamten 5 mg daily, titrated up to 15 mg based on the LVOT gradient and left ventricular ejection fraction.
- Control
- Matching placebo capsules.
- Primary outcome
- Composite of patients proceeding with septal reduction therapy or remaining guideline-eligible for it after 16 weeks.
- Results
- At 16 weeks, 43 of 56 placebo patients (76.8%) and 10 of 56 mavacamten patients (17.9%) met guideline criteria or underwent septal reduction therapy, a difference of 58.9% (95% CI: 44.0%-73.9%; P < 0.001). Hierarchically tested secondary outcomes also favored mavacamten, with a mean difference in post-exercise peak LVOT gradient of -37.2 mm Hg (P < 0.001).
- Conclusion
- In oHCM patients with intractable symptoms, mavacamten significantly reduced the proportion meeting guideline criteria for septal reduction therapy at 16 weeks.
- Why it matters
- It showed that a targeted drug therapy can avoid or delay an invasive procedure in patients who were already candidates for it, although long-term freedom from septal reduction remains to be determined.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 14, 2026