Abstract

Aims: Many patients with heart failure (HF) have chronic kidney disease (CKD) and may not tolerate mineralocorticoid receptor antagonists. We investigated the efficacy and safety of the novel mineralocorticoid receptor modulator balcinrenone in combination with dapagliflozin in a phase 2b study. Methods and results: From January 2021 to October 2023, we randomized 133 adults with symptomatic HF, ejection fraction <60%, estimated glomerular filtration rate (eGFR) ≥30 to ≤60 ml/min/1.73 m2 and urinary albumin‐to‐creatinine ratio (UACR) ≥30 to <3000 mg/g, to receive balcinrenone 15, 50 or 150 mg/day plus dapagliflozin 10 mg/day, or dapagliflozin 10 mg/day plus placebo, for 12 weeks. Enrolment was stopped early because of slow recruitment. Relative reductions in UACR from baseline to week 12 (primary endpoint) were not significantly different between the balcinrenone plus dapagliflozin groups versus dapagliflozin plus placebo. There was no clear balcinrenone dose–response relationship. There were possible dose‐dependent increases in serum potassium levels, reduced eGFR in the highest dose group, and non‐significant trends towards reduced N‐terminal pro‐B‐type natriuretic peptide levels. Hyperkalaemia adverse events led to discontinuation in two participants receiving balcinrenone plus dapagliflozin and none in those receiving dapagliflozin plus placebo. Conclusion: While the smaller than planned sample size limits interpretation, we did not see significant reduction in UACR in patients treated with balcinrenone plus dapagliflozin compared with dapagliflozin plus placebo.