A Study of Vericiguat (MK-1242) in Participants With Chronic Heart Failure With Reduced Ejection Fraction (HFrEF) (MK-1242-035)

Inclusion Criteria:

• History of chronic HF [New York Heart Association (NYHA) Class II to IV] onguideline-directed medical therapy for heart failure (GDMT) with no HFhospitalization within 6 months or outpatient IV diuretic use within 3 months beforerandomization.

• Left ventricular ejection fraction (LVEF) of ≤40%, assessed within 12 months beforerandomization by any imaging method.

• Elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) levels.

• A female participant is eligible to participate if she is not pregnant orbreastfeeding, is not a woman of childbearing potential (WOCBP), or is a WOCBP andagrees to follow contraceptive guidance during the study intervention period and forat least 1 month after the last dose of study intervention.

Exclusion Criteria:

• Has SBP <100 mm Hg or symptomatic hypotension.

• Awaiting heart transplantation, is receiving continuous IV infusion of an inotrope,or has or anticipates receiving an implanted ventricular assist device.

• Amyloidosis or sarcoidosis.

• Primary valvular heart disease requiring surgical procedure or intervention or hasundergone a valvular surgical procedure or intervention within 3 months beforerandomization.

• Hypertrophic cardiomyopathy.

• Acute myocarditis or Takotsubo cardiomyopathy.

• History of heart transplant.

• Tachycardia-induced cardiomyopathy and/or uncontrolled tachyarrhythmia.

• Acute coronary syndrome, or undergone coronary artery bypass grafting (CABG) orpercutaneous coronary intervention (PCI) within 3 months before randomization.

• History of symptomatic carotid stenosis, transient ischemic attack (TIA), or strokewithin 3 months before randomization.

• Malignancy or other noncardiac condition limiting life expectancy to <3 years.

• Requires continuous home oxygen for severe pulmonary disease.

• Interstitial lung disease.

• Discontinuation or dose modification of GDMT or vericiguat within 4 weeks beforerandomization.

• Recent history (within the last year) of drug or alcohol abuse or dependence.