Efficacy and safety of finerenone in adults with IgA nephropathy: a 12-month real-world study

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide and a leading cause of end-stage renal disease. Finerenone reduces proteinuria in diabetic kidney disease, but evidence in IgAN remains limited. This single-center retrospective study included adults with biopsy-proven IgAN who initiated finerenone therapy between January 2023 and December 2025 and were followed for at least 90 days. The primary outcomes included changes in 24-hour urinary protein (24hUP) and estimated glomerular filtration rate (eGFR), and subgroup analysis was performed in patients not receiving immunosuppressive therapy. A total of 52 patients were included (mean age 40.6 ± 9.7 years; 71.2% female). Median 24hUP decreased from 750.0 mg/24h at baseline to 496.0 mg/24h at Month 12 (median reduction 29.7%, p = 0.003), with significant reduction observed from Month 6. Among patients with baseline 24hUP ≥300 mg/24h, complete remission was achieved in 15.6% and partial remission in 15.6% at Month 12. In the non-immunosuppressive subgroup (n = 43), significant reduction was also found at Month 12 (p = 0.017). eGFR remained stable throughout follow-up (p = 0.873). Serum potassium increased slightly but remained clinically manageable, with only 3.8% of patients experiencing transient hyperkalemia (≥5.5 mmol/L), and no treatment discontinuations or serious adverse events occurred. Finerenone was associated with sustained proteinuria reduction and stable kidney function, with a favorable safety profile over 12 months.