Heart Failure

- Participant (male or female) must be aged 40 years and older.
- Diagnosis of heart failure with New York Heart Association(NYHA) class II–IV, ambulatory or hospitalized primarily for heart failure.
- On diuretic treatment for at least 30 days prior to randomization.
- Documented left ventricular ejection fraction (LVEF) of ≥40% measured by any modality within the last 12 months.
- Structural heart abnormalities based on any local imaging measurement within the last 12 months, defined by at least one of the following findings: left atrial diameter (LAD) ≥3.8cm, left atrial area (LAA) ≥20cm2, left atrial volume index (LAVI) >30 mL/m2, left ventricular mass index (LVMI) ≥115 g/m2 (♂)/ 95 g/m2 (♀), septal thickness or posterior wall thickness ≥1.1 cm
- n-terminal prohormone B-type natriuretic peptide (NT-proBNP) ≥300 pg/mL (BNP ≥100 pg/mL) in sinus rhythm and patient does not have an ongoing diagnosis of paroxysmal atrial fibrillation or NT-proBNP ≥900 pg/mL (BNP ≥300 pg/mL) in atrial fibrillation (or if atrial fibrillation status is unknown or if patient has an ongoing diagnosis of paroxysmal atrial fibrillation) for participants obtained at the following time:

• Within 90 days prior to randomization if patient had been hospitalized for heart failure (HF) requiring initiation or change in HF therapy or if patient had an urgent visit for HF requiring intravenous (IV) diuretic therapy, both within 90 days prior to randomization OR
• Within 30 days prior to randomization if patient has not been hospitalized for HF nor had an urgent HF visit within the past 90 days.

- Women of childbearing potential can only be included in the study if a pregnancy test is negative at screening and baseline and if they agree to use adequate contraception which is consistent with local regulations regarding the methods for contraception for those participating in clinical trials.

- Estimated glomerular filtration rate (eGFR) <25 mL/min/1.73 m² at either screening or randomization visit.
- Serum/plasma potassium >5.0 mmol/L at either screening or randomization visit.
- Acute inflammatory heart disease, e.g. acute myocarditis, within 90 days prior to randomization
- Myocardial infarction or any event which could have reduced the ejection fraction within 90 days prior to randomization
- Coronary artery bypass graft surgery in the 90 days prior to randomization
- Percutaneous coronary intervention in the 30 days prior to randomization
- Stroke or transient ischemic cerebral attack within 90 days prior to randomization
- Probable alternative cause of participants’ HF symptoms that in the opinion of the investigator primarily accounts for patient’s dyspnea such as significant pulmonary disease, anemia or obesity. Specifically, patients with the below are excluded: Severe pulmonary disease requiring home oxygen, or chronic oral steroid therapy, History of primary pulmonary arterial hypertension, Hemoglobin <10 g/dl, Valvular heart disease considered by the investigator to be clinically significant, Body Mass Index (BMI) >50 kg/m2 at screening
- Systolic blood pressure(SBP) ≥160 mmHg if not on treatment with ≥3 blood pressure lowering medications or ≥180 mmHg irrespective of treatments, on 2 consecutive measurements at least 2-minute apart, at screening or at randomization.
- Concomitant systemic therapy with potent cytochrome P450 isoenzyme 3A4 (CYP3A4) inhibitors (e.g. itraconazole, ritonavir, indinavir, cobicistat, clarithromycin) or moderate or potent CYP3A4 inducers, that cannot be discontinued 7 days prior to randomization and for the duration of the treatment period.