Experts Weigh In on Finerenone's Priority Review for CKD in Type 1 Diabetes

For more than 3 decades, patients with type 1 diabetes (T1D) and chronic kidney disease (CKD) have had few to no new therapeutic options specifically designed to slow kidney disease progression. That could soon change. The FDA has accepted a supplemental new drug application (sNDA) and granted priority review to finerenone (Kerendia; Bayer) for the treatment of adults with T1D and CKD, a regulatory milestone that experts say could reshape how clinicians approach this historically undertreated population.¹

The sNDA is supported by data from the phase 3 FINE-ONE trial (NCT05901831), a global, randomized, double-blind, placebo-controlled study that enrolled 242 adults with T1D, CKD (estimated glomerular filtration rate 25 to less than 90 mL/min/1.73 m²), and high-level albuminuria (urine albumin-creatinine ratio [uACR] 200 to less than 5000 mg/g) who were already receiving standard-of-care treatment with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. The trial met its primary end point, with finerenone reducing uACR from baseline by approximately 25% compared with placebo over 6 months (95% CI, 0.75 [0.65-0.87]; P = .0001). Additionally, 68.1% of patients receiving finerenone achieved a 30% or greater uACR reduction at any postbaseline time point, compared with 46.6% in the placebo group.¹

If approved for this indication, finerenone would become the first nonsteroidal mineralocorticoid receptor antagonist (MRA) indicated for adults with T1D and CKD. It would also represent the first positive phase 3 study result in this population in approximately 30 years.¹

To help pharmacists and clinicians understand the clinical and regulatory significance of this moment, Pharmacy Times spoke with leading experts in diabetic kidney disease: Hiddo J. L. Heerspink, PhD, principal investigator of the FINE-ONE trial and professor of clinical trials at the University Medical Center Groningen; and Katherine R. Tuttle, MD, FASN, FACP, FNKF, executive director for research at Providence Inland Northwest Health and professor of medicine at the University of Washington School of Medicine.

Hiddo J. L. Heerspink, PhD

Hiddo J. L. Heerspink, PhD, discusses the rationale behind FINE-ONE's trial design, including why uACR was selected as a bridging biomarker rather than hard kidney outcomes and why regulators agreed this approach was sufficient to support an sNDA submission. He also explains how finerenone's mechanism as a nonsteroidal MRA fills a critical therapeutic gap in T1D that sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) cannot currently address.

Pharmacy Times: FINE-ONE enrolled just 242 participants over 6 months, using uACR reduction as a bridging biomarker rather than hard kidney outcomes. What gave you and the steering committee confidence that this trial design would be sufficient to support an sNDA submission to the FDA?

Hiddo J. L. Heerspink, PhD: We showed that albuminuria fulfills all criteria for a valid bridging biomarker to translate the kidney protective effects of finerenone from type 2 to T1D. Following discussions with regulators, they agreed that albuminuria in finerenone clinical trials can be accepted as a bridging biomarker since 87% of the benefit of finerenone in reducing the risk of kidney failure in type 2 diabetes [T2D] was explained by the reduction in albuminuria. The FINE-ONE data thus support a long-term kidney protective effect with finerenone in patients with T1D and CKD.²

Pharmacy Times: As someone who has led major CKD trials across multiple drug classes, how does finerenone's mechanism as a nonsteroidal MRA fill a gap that SGLT2 inhibitors and renin-angiotensin system blockade cannot address on their own in patients with T1D and CKD?

Heerspink: MRA overactivation is implicated in many types of kidney diseases, including diabetes (both type 1 and type 2) as well as other nephropathies. In patients with T1D, SGLT2 inhibitors are not indicated because of the risk of diabetic ketoacidosis. The efficacy and safety of GLP-1 RAs are not assessed in well-designed global clinical trials in patients with T1D and CKD, and thus, they are also not recommended for use in these patients. Finerenone is thus the first drug in 30 years, since the demonstration of captopril (Capoten) as a kidney-protective drug, that has the potential to improve kidney outcomes on top of renin-angiotensin system inhibition.

Katherine R. Tuttle, MD, FASN, FACP, FNKF

Katherine R. Tuttle, MD, FASN, FACP, FNKF, contextualizes the magnitude of the unmet need in patients with T1D and CKD—including the striking statistic that 1 in 10 people with T1D in the US require kidney replacement therapy. She also outlines the patient profile most likely to benefit from finerenone and addresses the primary safety consideration clinicians should weigh before initiating therapy: hyperkalemia.

Pharmacy Times: Your research has helped establish how prevalent CKD is among adults with T1D in the US. Given that burden, how significant is the FDA's priority review of finerenone for this patient population, and what does it signal about the direction of diabetic kidney disease care?

Katherine R. Tuttle, MD, FASN, FACP, FNKF: This is the first therapy in more than 3 decades that has been tested and shown benefit for people with T1D and CKD. The unmet need is enormous, as the T1D population is now living longer but with a high burden of comorbidity, prominently CKD. Indeed, in current US health care systems, 1 in 10 people with T1D require kidney replacement therapy by dialysis or transplant.³

Pharmacy Times: From a precision medicine standpoint, what patient profile would make someone with T1D and CKD a strong candidate for finerenone therapy, and are there clinical factors that would give you pause before prescribing it?

Tuttle: The FINE-ONE trial enrolled people with type 1 diabetes and high-level albuminuria [uACR of 200 mg/g or higher] because it is a strong predictor for loss of kidney function and kidney failure. Moreover, in [patients with] T2D with CKD, reduction in albuminuria explained 80% of the benefit on these “hard” clinical outcomes. So, uACR can be considered a “bridging biomarker,” meaning that its reduction is highly likely to infer reduced risk of adverse clinical outcomes. Therefore, finerenone should be considered for people with T1D, like those in FINE-ONE, who have high-level albuminuria and are at risk for losing kidney function and kidney failure.

The main [adverse] effect that would give me pause is hyperkalemia. In general, finerenone, as well as other agents that interrupt the renin-angiotensin and aldosterone system, may cause hyperkalemia. Therefore, potassium should be normal when these agents are initiated and monitored closely in people with CKD. With this approach, hyperkalemia was rare and manageable without the need for treatment discontinuation for most people in the FINE-ONE study.

REFERENCES

1. Halpern L. FDA grants priority review to finerenone for chronic kidney disease in adults with type 1 diabetes. Pharmacy Times. May 25, 2026. Accessed May 27, 2026. https://www.pharmacytimes.com/view/fda-grants-priority-review-to-finerenone-for-chronic-kidney-disease-in-adults-with-type-1-diabetes

2. Heerspink HJL, Birkenfeld AL, Cherney DZI, et al. Rationale and design of a randomised phase III registration trial investigating finerenone in participants with type 1 diabetes and chronic kidney disease: the FINE-ONE trial. Diabetes Res Clin Pract. 2023;204:110908. doi:10.1016/j.diabres.2023.110908

3. Tuttle KR, Ji L, Mathieu C, Rosen J. Addressing unmet needs for chronic kidney disease treatment in type 1 diabetes: a review. Diabetes Obes Metab. 2025;28(1):16-26. doi:10.1111/dom.70180