Amgen and Cytokinetics' Heart Failure Drug Omecamtiv Mecarbil Meets Primary Endpoint in Phase 3 Trial but Fails to Extend Patient Survival

Compiled by Fan Dongdong

Amgen and Cytokinetics’ jointly developed heart failure drug, omecamtiv mecarbil, achieved significant success in a Phase 3 study by meeting the primary endpoint of reducing the risk of hospitalization and other urgent treatments in patients with chronic heart failure; however, the drug failed to demonstrate a survival benefit in the trial.

The Galactic-HF study enrolled more than 8,000 patients over a four-year (208-week) period. The trial aimed to evaluate whether omecamtiv mecarbil could reduce the proportion of patients requiring hospitalization or other emergency treatment due to heart failure, and whether treatment with the drug could prolong patient survival. Participants in the trial had heart failure with reduced ejection fraction (HFrEF), a condition in which the heart muscle cannot contract effectively.

Regarding the trial results, the two companies stated in a press release that omecamtiv mecarbil met the primary endpoint in this study, reducing the time to patient death or the need for heart failure treatment by 8% compared with placebo, but the drug failed to meet the secondary endpoint of prolonging patient survival.

JPMorgan analyst Cory Kasimov wrote in a report to clients on Thursday that the trial data for omecamtiv mecarbil were both encouraging and disappointing, adding that the failure to meet secondary endpoints raises doubts about the therapeutic prospects of the product. Kasimov noted that merely reducing treatment risk “does not appear impressive.”

The two companies are further analyzing the data from this study and plan to present these findings at the American Heart Association’s Scientific Sessions next month.

Omecamtiv mecarbil, initially developed by Cytokinetics, is a cardiac myosin activator. This drug binds to the catalytic domain of cardiac myosin ATPase, accelerating the actin enzymatic cycle and modulating it to an optimal force-generating state. Furthermore, the drug enhances the heart’s pumping capacity in patients by strengthening the interaction between myosin heads and actin filaments in the myocardium. In 2006, Cytokinetics entered into a collaboration agreement with Amgen. In 2013, the French pharmaceutical company Servier acquired the rights to market the drug in Europe.

Notably, similar trial results were observed for vericiguat, a heart failure drug co-developed by Merck & Co. and Bayer. In a Phase 3 study enrolling more than 5,000 patients, vericiguat significantly reduced the composite risk of heart failure hospitalization and cardiovascular death following worsening events by 10% compared with placebo, with a favorable safety and tolerability profile. Vericiguat had already received Priority Review designation from the U.S. Food and Drug Administration (FDA) in July, with a decision on marketing approval expected by January 2021.

Reference source: Amgen heart failure med, in 'unimpressive' showing, hits phase 3 goal—but doesn’t extend patients’ lives

Original Title: Amgen’s Heart Failure Drug Omecamtiv Mecarbil Meets Primary Endpoint in Phase 3 Trial, but Fails to Prolong Patient Survival