Background: Anemia is common in patients with chronic kidney disease and type 2 diabetes. Finerenone improved heart and kidney outcomes in patients with chronic kidney disease and type 2 diabetes in FIDELITY.

Objective: This post hoc analysis investigated the efficacy and safety of finerenone vs placebo by baseline anemia status.

Methods: Anemia was defined as serum hemoglobin levels <13 g/dL (male) or <12 g/dL (female) or treatment with an erythropoiesis-stimulating agent at baseline. Outcomes included cardiovascular (CV) and kidney composites, hospitalization for heart failure, and all-cause mortality. Safety was assessed through treatment-emergent adverse events.

Results: Of 12,971 patients, 33% had anemia at baseline. Finerenone reduced the risk of the CV composite outcome to a greater extent in patients with vs without anemia (HR: 0.75 [95% CI: 0.65-0.88] vs HR: 0.93 [95% CI: 0.82-1.05]; P for interaction = 0.03). Finerenone reduced the risk of the kidney composite outcome vs placebo, with no heterogeneity between patients with vs without anemia (HR: 0.79 [95% CI: 0.65-0.95] and HR: 0.74 [95% CI: 0.60-0.91]; P for interaction = 0.77). The risk of hospitalization for heart failure and all-cause mortality was lower with finerenone vs placebo, irrespective of anemia status. Patients with anemia experienced higher incidence of treatment-emergent hyperkalemia vs those without.

Conclusions: Finerenone demonstrated CV and kidney benefit in patients with and without anemia. The benefit of finerenone on CV outcomes was greater in patients with vs without anemia at baseline. Anemia is likely a marker for higher-risk patients who are more susceptible to the benefits of finerenone. (Efficacy and Safety of Finerenone in Subjects With Type 2 Diabetes Mellitus and Diabetic Kidney Disease [FIDELIO-DKD], NCT02540993; Efficacy and Safety of Finerenone in Subjects With Type 2 Diabetes Mellitus and the Clinical Diagnosis of Diabetic Kidney Disease [FIGARO-DKD], NCT02545049).