What is the comparison between finerenone (Finerenone) and spironolactone (Spironolactone) for treating chronic kidney disease (CKD) and heart failure?

Finerenone vs. Spironolactone: Clinical Comparison

Finerenone is the preferred mineralocorticoid receptor antagonist (MRA) for patients with type 2 diabetes and chronic kidney disease, offering superior safety with significantly lower hyperkalemia risk compared to spironolactone while providing equivalent or superior cardiovascular and renal protection. 1, 2

Key Differentiating Features

Efficacy Profile

Cardiovascular Outcomes:

• Finerenone demonstrates a 13% reduction in composite cardiovascular endpoints (cardiovascular death, MI, stroke, heart failure hospitalization) in patients with diabetic kidney disease 3, 4
• The benefit is primarily driven by a 29% reduction in heart failure hospitalizations (HR 0.71,95% CI 0.56-0.90) 3, 4
• In head-to-head comparisons, finerenone 20 mg shows better mortality outcomes compared to eplerenone and comparable renal outcomes to spironolactone 5

Renal Protection:

• Finerenone provides a 23% reduction in composite kidney outcomes (sustained ≥57% decrease in eGFR or renal death) 3
• Notable 36% reduction in end-stage kidney disease (HR 0.64,95% CI 0.41-0.995) 3, 4
• Benefits observed across eGFR range of 25-90 mL/min/1.73 m² 3

Safety Advantages Over Steroidal MRAs

Hyperkalemia Risk:

• Finerenone causes significantly less hyperkalemia than both spironolactone and eplerenone 5, 6
• Hyperkalemia incidence with finerenone: 10.8% vs. 5.3% placebo 4
• Treatment discontinuation due to hyperkalemia: only 1.2-2.3% with finerenone 4, 6
• No deaths related to hyperkalemia in major trials 4
• At 10 mg/d, finerenone shows lower serum potassium levels compared to 25-50 mg/d steroidal MRAs (MD = -0.14,95% CI -0.30 to 0.02) 6

Renal Function Preservation:

• Finerenone demonstrates higher eGFR compared to steroidal MRAs (MD = 2.07,95% CI -0.04 to 4.17), making it safer for patients with CKD 6

Hormonal Side Effects:

• Finerenone has no effect on sexual side effects including gynecomastia, unlike spironolactone 5
• No impact on body weight 5

Clinical Algorithm for MRA Selection

Choose Finerenone When:

• Patient has type 2 diabetes with CKD (eGFR 25-90 mL/min/1.73 m²) and albuminuria (UACR ≥30 mg/g) 2, 3
• Already on maximum tolerated RAS inhibitor (ACE-I or ARB) 1, 2
• Baseline potassium ≤4.8 mmol/L 2, 3
• Goal is combined cardiovascular and renal protection 1, 3
• Patient has CKD with higher hyperkalemia risk (safer profile) 5, 6

Consider Spironolactone When:

• Patient has resistant hypertension with eGFR ≥45 mL/min/1.73 m² 1
• No diabetes present and primary indication is blood pressure control 1
• Cost is a major barrier (spironolactone is generic) [general medical knowledge]

Do NOT Use Either When:

• eGFR <25 mL/min/1.73 m² or patient on dialysis 2
• Baseline potassium >4.8 mmol/L 2, 3
• End-stage renal disease 2

Dosing Comparison

Finerenone:

• Start 10 mg daily if eGFR 25-60 mL/min/1.73 m² 2, 3
• Start 20 mg daily if eGFR >60 mL/min/1.73 m² 2, 3
• Uptitrate to 20 mg after 1 month if potassium ≤4.8 mmol/L 2

Spironolactone:

• Typical dosing 25-50 mg daily for resistant hypertension 6
• Higher doses associated with greater hyperkalemia risk 6

Monitoring Requirements

Both agents require:

• Verify potassium ≤4.8 mmol/L before initiation 2, 3
• Regular potassium monitoring after starting 2, 3
• Withhold if potassium >5.5 mmol/L 2
• Restart at lower dose when potassium returns to ≤5.0 mmol/L 2

Treatment Sequencing in Diabetic CKD

Recommended order per KDIGO 2022: 1, 2

1. RAS inhibitor (ACE-I or ARB) at maximum tolerated dose
2. SGLT2 inhibitor (prioritized over finerenone for larger effects)
3. Finerenone (if persistent albuminuria despite above, or SGLT2i intolerance)

Finerenone can be used alongside SGLT2 inhibitors for complementary cardiorenal protection 3, though definitive data on this combination is still emerging 1

Common Pitfalls to Avoid

• Do not use spironolactone in diabetic CKD when finerenone is available - the safety profile strongly favors finerenone 5, 6
• Do not initiate finerenone without first optimizing RAS inhibitor therapy 2
• Do not continue either agent if potassium persistently >5.5 mmol/L despite dietary modification 2
• Do not use finerenone in heart failure with reduced ejection fraction - this population was excluded from FIGARO-DKD 3

Guideline Support

KDIGO 2022 explicitly states that finerenone is currently the only nonsteroidal MRA with proven clinical kidney and cardiovascular benefits 1, representing a Grade A recommendation for patients with T2D, persistent albuminuria (ACR >30 mg/g), and non-elevated potassium despite maximal RAS inhibition 1