Finerenone Versus Spironolactone for Cardio-Oncology Patients With Heart Failure: Comparative Outcomes from a Propensity-Matched Analysis

Finerenone is a novel nonsteroidal mineralocorticoid-receptor antagonist (MRA) that reduces adverse cardiovascular and renal outcomes in patients with chronic kidney disease and diabetes. Its comparative effectiveness against steroidal MRAs in cardio-oncology patients with higher clinical burden remains unknown. We aim to evaluate whether finerenone use in cardio-oncology patients is associated with reduced heart failure admissions and hyperkalemia events compared with spironolactone over 1 year. Secondary exploratory outcomes were also analyzed. We conducted a retrospective observational analysis using the TriNetX database comprising adults with a history of cancer, heart failure with a baseline ejection fraction ≥40%, and MRA initiation. Cardiovascular and renal outcomes were compared over 1 year of drug initiation after 1:1 propensity matching using Cox proportional hazard ratios (HRs). A total of 872 matched patients were included (mean age = 72, 45% female, 50% white, 23% receiving chemotherapy, 69% chronic kidney disease, and 90% diabetes). Finerenone users were associated with a lower risk of heart failure exacerbation (HR 0.51; 95% CI 0.35-0.76), all-cause mortality (HR 0.41; 95% CI 0.21-0.80), severe hyperkalemia (HR 0.57; 95% CI 0.40-0.83), and renal failure (HR 0.71; 95% CI 0.54-0.93) compared to spironolactone over 1 year. Individual risk of stroke was not different; however, composite major adverse cardiac events was lower with finerenone (HR 0.67; 95% CI 0.51-0.88), driven primarily by fewer heart failure events. In conclusion, finerenone was associated with fewer cardiac and renal adverse events with lower observed mortality compared with spironolactone in patients with a cancer history and heart failure (left ventricular ejection fraction ≥40%).