Cytokinetics and Amgen's omecamtiv mecarbil shows promising results in mid-stage heart failure study

• Final results from the expansion phase of a Phase 2 study, COSMIC-HF, evaluating Cytokinetics' (NASDAQ:CYTK) and collaboration partner Amgen's (NASDAQ:AMGN) omecamtiv mecarbil in patients with chronic heart failure were presented today at the American Heart Association Scientific Sessions in Orlando, FL. The study met is primary endpoints of determining the maximum and pre-dose plasma concentration of omecamtiv mecarbil and met all secondary endpoints of improvements in various measures of cardiac function compared to placebo.
• The expansion phase was designed to assess orally available omecamtiv mecarbil in 448 subjects with chronic heart failure with left ventricular systolic dysfunction. Patients were randomized 1:1:1 to receive placebo, omecamtiv mecarbil 25 mg twice daily or omecamtiv mecarbil 25 mg twice daily titrated up to 50 mg twice daily after two weeks at 25 mg. ~60% of the titrated subjects escalated to the 50 mg dose.
• After 20 weeks of treatment, statistically significant improvements versus placebo were observed in the dose titration group in six measures of cardiac function, highlighted by an increase in systolic ejection time by 25.0 msec (p<0.001), increase in stroke volume by 3.63 mL (p=0.022) and a decrease in heart rate of 2.97 beats/min (p=0.007). The effects were slightly less profound in the 25 mg cohort with statistically significant improvements in systolic ejection time, stroke volume and a heart failure biomarker called NT-proBNP.
• Adverse events were comparable to placebo although there was an increase in unstable angina (0.34%) in the omecamtiv mecarbil group versus placebo (0%). There was also a 62% (n=278/448) incidence of increased troponin in the omecamtiv mecarbil cohorts. Troponins are proteins found in heart muscle that are released into the blood when the heart is damaged.
• Omecamtiv mecarbil is a cardiac myosin activator. Myosin is a protein in heart muscle this is responsible for converting chemical energy into the mechanical energy that results in a heart beat. Cardiac myosin activators increase systolic ejection time which results in an increase in cardiac contractility and more oxygen-efficient cardiac function.
• Previously: Amgen and Cytokinetics' omecamtiv mecarbil shows positive effect in mid-stage heart failure study (Oct. 27)
• Previously: Patient enrollment complete in trial expansion phase of Cytokinetics' heart drug (March 13)