• To evaluate pharmacokinetics (PK) of omecamtiv mecarbil in Japanese subjects with heart failure (HF) with reduced ejection fraction
• To evaluate the safety and tolerability of oral omecamtiv mecarbil

This study was conducted by Amgen as the IND holder, with Cytokinetics as a collaborator. Due to the termination of the collaboration agreement between Amgen and Cytokinetics in May 2021 and subsequent transfer of the omecamtiv mecarbil IND from Amgen to Cytokinetics, Cytokinetics is now listed as the sponsor.

Inclusion Criteria:

• Japanese male or female ≥ 20 years and ≤ 85 years of age
• History of chronic stable heart failure (HF) with reduced ejection fraction, defined as requiring treatment for HF for a minimum of 4 weeks prior to screening
• Treated for HF with optimal pharmacological therapy
• Left ventricular ejection fraction ≤ 40% at screening

Exclusion Criteria:

• Severe uncorrected valvular heart disease
• Hypertrophic obstructive cardiomyopathy, active myocarditis, constrictive pericarditis, or clinically significant congenital heart disease
• Acute myocardial infarction, unstable angina, or persistent angina at rest within 30 days prior to randomization
• Systolic blood pressure (BP) > 160 mmHg or < 90 mmHg, or diastolic BP > 90 mmHg, or heart rate (HR) > 110 beats per minute (bpm) or HR < 50 bpm
• Estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m^2
• Total bilirubin (TBL) ≥ 2x upper limit of normal (ULN), or alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥ 3x ULN Other Exclusion Criteria may apply.