Aficamten's Phase III Success Will Change the Landscape of HCM Treatment
Cytokinetics announced positive results from the Phase III MAPLE-HCM trial of its drug aficamten for the treatment of obstructive hypertrophic cardiomyopathy (oHCM).
Cytokinetics recently announced results from the Phase III MAPLE-HCM trial of its experimental cardiac myosin inhibitor, aficamten, showing significant efficacy compared to the traditional beta-blocker metoprolol in the treatment of obstructive hypertrophic cardiomyopathy (oHCM). Over 24 weeks, peak oxygen uptake (pVO₂) increased by an average of 1.1 mL/kg/min in the aficamten group, compared to a deterioration of 1.2 mL/kg/min in the metoprolol group. 51% of patients achieved at least one improvement in NYHA class, compared to only 26% in the metoprolol group. Quality of life and cardiac biomarkers also significantly improved. Regarding safety, only 4.5% of patients in the aficamten group required dose reductions, significantly lower than the 30% in the metoprolol group. The drug is currently under FDA review, with approval delayed until December 26th due to the submission of a regulatory information management system (REMS) documentation.
Aficamten will compete with Bristol-Myers Squibb's (BMS) Camzyos, which was approved in 2022 and expected to generate $602 million in sales in 2024. However, it failed to reach endpoints in a Phase III trial for non-obstructive HCM this year. Cytokinetics' CEO believes aficamten is safer and could expand its market—currently, only 5% of oHCM patients use Camzyos, with a total potential patient population of 200,000 to 250,000. Cytokinetics is also advancing Phase III trials for non-obstructive and pediatric oHCM and preparing for a commercial launch.
In terms of international collaborations, Sanofi and Bayer have respectively acquired rights to aficamten in China and Japan, easing pressure on Cytokinetics. Edgewise Therapeutics' EDG-7500 is in Phase II but has been associated with serious adverse events. Aficamten's breakthrough could disrupt decades-old treatment standards for oHCM, accelerating competition and innovation in the field.