Cytokinetics: Positive Topline Results in Cardiomyopathy Trial

 Phase 2 Clinical Trial of CK-274 Demonstrated Consistent and Clinically Meaningful Reductions in Left Ventricular Outflow Tract Gradients Within Two Weeks in Patients with Obstructive Hypertrophic Cardiomyopathy

No Treatment Interruptions or Discontinuations Due to Reduction in Left Ventricular Ejection Fraction

Phase 3 Registrational Trial of CK-274 Expected to Start Before Year End

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Cytokinetics, Incorporated (Nasdaq: CYTK) today announced positive topline results from Cohorts 1 and 2 of REDWOOD-HCM (Randomized Evaluation of Dosing With CK-274 in Obstructive Outflow Disease in HCM), the Phase 2 clinical trial of CK-3773274 (CK-274), an investigational next-generation cardiac myosin inhibitor in development for the potential treatment of hypertrophic cardiomyopathy (HCM). The results of REDWOOD-HCM inform dose selection and support progression of CK-274 to a planned Phase 3 registrational clinical trial which is expected to start before year end.

Results from Cohorts 1 and 2 of REDWOOD-HCM demonstrated that treatment with CK-274 for 10 weeks resulted in statistically significant reductions from baseline compared to placebo in the average resting left ventricular outflow tract pressure gradient (LVOT-G) (p=0.0003, p=0.0004, Cohort 1 and Cohort 2, respectively) and the average post-Valsalva LVOT-G (p=0.001, p<0.0001, Cohort 1 and Cohort 2, respectively). The majority of patients treated with CK-274 (78.6% in Cohort 1 and 92.9% in Cohort 2) achieved the target goal of treatment, defined as resting gradient <30 mmHg and post-Valsalva gradient <50 mmHg at Week 10 compared to placebo (7.7%). Reductions in LVOT-G occurred within two weeks of initiating treatment with CK-274, were maximized within two to six weeks of the start of dose titration, and were sustained until the end of treatment at 10 weeks. The observed reductions in LVOT-G were dose dependent, with patients achieving greater reductions of LVOT-G with increasing doses of CK-274.

Treatment with CK-274 in REDWOOD-HCM was generally well tolerated. The incidence of adverse events was similar between treatment arms. No serious adverse events were attributed to CK-274 and no treatment interruptions occurred on CK-274. No new cases of atrial fibrillation in patients treated with CK-274 were reported. In this dose-range finding trial, one patient experienced a transient decrease in left ventricular ejection fraction (LVEF) that required dose adjustment but not dose interruption. LVEF returned to baseline within two weeks after the end of treatment in both cohorts, which was consistent with the reversibility of LVEF decreases that were similarly observed in healthy participants in the Phase 1 study of CK-274.

https://www.globenewswire.com/news-release/2021/07/19/2264759/0/en/Cytokinetics-Announces-Positive-Topline-Results-of-Redwood-HCM.html