Cytokinetics detailed results on Monday from a late-stage trial of aficamten for a rare heart disease, and the company is already hiring medical affairs and payer interaction staff as it prepares for a potential launch.
“The study hit on not only its primary endpoint, but all pre-specified endpoints,” CEO Robert Blum told Endpoints News in an interview. “The magnitude of effects are quite significantly large and clinically meaningful.”
Cytokinetics plans to submit an NDA for aficamten in the third quarter of 2024, followed by a marketing authorization application in Europe in the fourth quarter and a 2025 launch, Blum said.
In December, Cytokinetics reported that its myosin inhibitor had met the primary endpoint in a Phase 3 trial for obstructive hypertrophic cardiomyopathy (HCM), but did not detail figures. The following month, there was speculation that Cytokinetics would be acquired by Novartis. CEO Vas Narasimhan later dismissed the news reports.
On Monday, Cytokinetics said that in the Phase 3 SEQUOIA-HCM trial, aficamten increased peak oxygen uptake by 1.8 ml/kg/min from baseline versus zero increase for placebo (p=0.000002). The drug also reached statistical significance in all 10 secondary endpoints.
The trial recruited 282 people with HCM taking standard of care beta-blockers, calcium channel blockers, disopyramide or some combination of these drugs. Subjects in the aficamten arm were given one of four doses based on the results of echocardiography assessments for up to 24 weeks.
Blum said the company intends to commercialize the drug independently in the US and Europe, and has learning and development analytics in place, along with planning functions associated with marketing and sales leadership. In April, GlobalData projected the drug could reach $658 million in US sales by 2033.
In 2020, Cytokinetics sold the exclusive China and Taiwan rights for aficamten to Ji Xing Pharmaceuticals for $250 million in “committed capital” and up to $200 million in milestones as well as sales royalties. “We’re in dialogue right now with several potential partners for aficamten in Japan,” Blum said.
Aficamten would compete with Bristol Myers Squibb’s myosin inhibitor Camzyos, which won FDA approval two years ago for symptomatic New York Heart Association class II-III obstructive HCM. As a “next-in-class” compound, aficamten could be relevant for a “broader array” of patients, Blum said.
Camzyos carries a black box warning for heart failure from left ventricular ejection fraction (LVEF) and is subject to a risk evaluation and mitigation strategy. In the Phase 3 aficamten trial, there were no major adverse cardiovascular events due to the drug, Cytokinetics said.
Serious adverse events occurred in less than 6% of aficamten patients and none were deemed related to treatment. There was a “modest” 4.8% placebo-corrected reduction in treated patients’ LVEF but there were no associated dose interruptions.
“We believe [Camzyos’s] relatively sub-optimal benefit-risk profile has deterred market uptake,” B. Riley analysts said earlier this month.
Despite quarterly sales increases for Camzyos, the majority of obstructive HCM patients are still untreated, leaving a gap for Cytokinetics, they added. Camzyos reached $231 million in 2023 sales.