In this study, patients with heart failure with an ejection fraction < 60% and CKD (eGFR ≥ 20 to ≤ 60ml/min/1.73m2) will be treated with different doses of AZD9977 in combination with the SGLT2-inhibitor dapaglifozin (10 mg) or dapaglifozin (10 mg) alone (NCT04595370). The gene discussed is SLC5A2; the disease is heart failure.