The question of how to treat non-obstructive hypertrophic cardiomyopathy has long perplexed researchers and pharmaceutical developers alike, but topline results from Cytokinetics’ Phase 3 ACACIA-HCM trial suggest MYQORZO (aficamten) could be the answer.
- HCM is commonly characterized by thickened heart muscle that struggles to relax, but in the non-obstructive form, this enlarged tissue doesn’t block blood leaving the heart.
- Since there’s no “obstruction” to remove or chemically treat, clinicians have to rely on off-label symptom management that often falls short.
For Cytokinetics, aficamten already saw success in obstructive HCM, so the hypothesis of ACACIA-HCM was simple – can the drug help patients with the more common, non-obstructive form?
To test this, researchers randomized 516 patients with symptomatic nHCM to receive either aficamten or placebo for 36 weeks and the results were a success across the study’s endpoints.
- For the primary endpoint, aficamten led to significant improvements compared to placebo in KCCQ scores (11.4 vs. 8.4) and peak VO2 (0.64 vs -0.03).
- Aficamten also led to statistically significant improvements in NYHA class and NT-proBNP levels.
To understand how important those results are, the only other HCM drug, Bristol Myers Squibb’s CAMZYOS (mavacamten) failed to improve symptoms and pVO2 in the ODYSSEY-HCM trial for nHCM.
- As such, if ACACIA-HCM can lead aficamten to an expanded approval for non-obstructive HCM, it would be the sole therapeutic for 60% of diagnosed HCM patients.
Wall Street’s reaction also underscored the importance of these study results…
- Cytokinetics’ stock surged roughly 14% on the news.
- Meanwhile BMS shed 2%.
However, the trial also highlighted the need for careful monitoring.
- While no new safety issues emerged, 10% of participants on aficamten experienced a drop in LVEF to below 50%, compared to just 1% in the placebo group.
The Takeaway
Cytokinetics’ MYQORZO already showed better outcomes than the competition in oHCM, but it seems like the drug could be headed toward dominance in non-obstructive HCM as well. That’s a win for HCM patients, the majority of whom still don’t have a pharmaceutical option, and an obvious win for Cytokinetics.
