Finerenone in Type 1 Diabetes with Diabetic Kidney Disease
Finerenone is not currently recommended for patients with type 1 diabetes and diabetic kidney disease, as all evidence and regulatory approval is limited exclusively to type 2 diabetes. 1, 2
Current Evidence Base and Guideline Recommendations
The KDIGO 2022 guidelines explicitly state that finerenone recommendations apply to "T2D only," while other therapies like RAS inhibitors and statins apply to "All patients (T1D and T2D)." 1, 2 This distinction is critical—the landmark trials (FIDELIO-DKD and FIGARO-DKD) that established finerenone's efficacy enrolled only patients with type 2 diabetes, creating a complete absence of safety and efficacy data in type 1 diabetes populations. 1, 3
The FDA approval and all major clinical guidelines (KDIGO, ADA) specify type 2 diabetes as the sole indicated population for finerenone. 2
What Should Be Used Instead for Type 1 Diabetes
For patients with type 1 diabetes and diabetic kidney disease, focus on the following evidence-based therapies that have demonstrated benefit across both diabetes types:
- RAS inhibitor (ACE inhibitor or ARB) at maximum tolerated dose if hypertension is present 2
- Moderate- or high-intensity statin for cardiovascular protection 1, 2
- Blood pressure control targeting individualized BP goals 2
- Dihydropyridine calcium channel blocker and/or diuretic as needed for BP control 2
Notably, SGLT2 inhibitors also lack sufficient data for recommendation in type 1 diabetes with CKD, as these populations were excluded from the major trials. 1
Future Prospects: The FINE-ONE Trial
A phase III trial (FINE-ONE, NCT05901831) is currently underway to evaluate finerenone specifically in type 1 diabetes patients with CKD. 4 This randomized, placebo-controlled trial is enrolling approximately 220 adults with type 1 diabetes, UACR ≥200-<5000 mg/g, and eGFR ≥25-<90 mL/min/1.73 m². 4 The primary endpoint is relative change in UACR over 6 months, using this as a bridging biomarker based on regulatory authority feedback. 4
If this trial demonstrates efficacy, finerenone could become the first registered treatment for CKD associated with type 1 diabetes in almost 30 years. 4 However, until these results are available and regulatory approval is obtained, finerenone remains contraindicated for this population.
Critical Pitfall to Avoid
Do not extrapolate the type 2 diabetes evidence to type 1 diabetes patients, even if they have similar kidney disease characteristics. The pathophysiology of diabetic kidney disease differs between type 1 and type 2 diabetes, and the safety profile—particularly regarding hyperkalemia risk (14% vs 6.9% in type 2 diabetes trials)—has not been established in type 1 diabetes. 1