The pharmaceutical landscape for diabetic complications has reached a significant milestone following the U.S. Food and Drug Administration’s (FDA) decision to expand the indication for Bayer’s KERENDIA (finerenone). This approval marks the first time in over three decades that a new pharmacological intervention has been authorized to specifically address the progression of chronic kidney disease (CKD) in adult patients living with type 1 diabetes (T1D). Concurrently, the metabolic health sector is witnessing further transformation as Arrowhead Pharmaceuticals releases late-breaking Phase 3 data for plozasiran, an investigational RNA interference (RNAi) therapeutic aimed at treating severe hypertriglyceridemia (sHTG) and preventing acute pancreatitis.
The FDA’s decision regarding KERENDIA followed a Priority Review of the supplemental New Drug Application (sNDA), a designation reserved for treatments that offer significant improvements in the safety or effectiveness of the treatment, diagnosis, or prevention of serious conditions. The new indication focuses on the reduction of the urinary albumin-to-creatinine ratio (UACR), a critical biomarker of kidney damage. By lowering UACR, the treatment is expected to mitigate the risk of sustained decline in estimated glomerular filtration rate (eGFR) and the eventual onset of end-stage kidney disease (ESKD).
The Clinical Evolution of Finerenone and the FINE-ONE Trial
The expansion of KERENDIA’s label into the type 1 diabetes population is rooted in the results of the FINE-ONE clinical trial (NCT05901831). This pivotal, global, randomized, double-blind, placebo-controlled Phase III study was designed to evaluate the efficacy and safety of finerenone when added to the standard of care—typically consisting of maximum tolerated doses of ACE inhibitors or angiotensin receptor blockers (ARBs).
The trial enrolled 242 adult participants with CKD associated with T1D. The primary objective was to demonstrate whether finerenone (at doses of 10 mg or 20 mg once daily) could achieve a superior reduction in UACR compared to a placebo over a six-month period. Results presented at the American Society of Nephrology (ASN) Kidney Week 2025 and subsequently published in the New England Journal of Medicine confirmed that the drug met its primary endpoint. The reduction in albuminuria is considered a "bridging" marker; because the relationship between UACR reduction and long-term kidney preservation was already established in Bayer’s previous trials for type 2 diabetes (FIDELIO-DKD and FIGARO-DKD), the FDA accepted these results as evidence of long-term clinical benefit for T1D patients as well.
Dr. Janet McGill, Professor of Medicine at Washington University School of Medicine in St. Louis and Co-Chair of the study’s Executive Committee, emphasized the historical weight of this approval. She noted that for more than 30 years, the medical community had been unable to offer T1D patients new options to slow the relentless progression of kidney decay. The approval addresses a substantial unmet need, as T1D patients often face a high lifetime risk of renal failure despite intensive glucose and blood pressure management.
Understanding the Mechanism: Non-Steroidal MRA vs. Traditional Therapy
Finerenone represents a shift in how clinicians approach mineralocorticoid receptor (MR) overactivation. Traditional steroidal MR antagonists (MRAs), such as spironolactone or eplerenone, have been available for decades but are often limited by side effects, including hyperkalemia (dangerously high potassium levels) and hormonal imbalances. Finerenone is a non-steroidal MRA, which allows it to bind more selectively and potently to the MR.
In the context of CKD, MR overactivation is a primary driver of inflammation and fibrosis (scarring) in the kidneys and the cardiovascular system. By blocking these receptors, KERENDIA targets the underlying structural damage of the kidney rather than just managing systemic blood pressure or blood glucose. This mechanistic advantage is why the drug has seen a rapid expansion in its approved uses. Since its initial approval in 2021 for CKD in type 2 diabetes, it has also received approval (in July 2025) for reducing cardiovascular risks in patients with heart failure and a left ventricular ejection fraction (LVEF) of 40% or higher.
Breakthroughs in Lipid Management: Plozasiran and the SHASTA Studies
While Bayer solidifies its position in the renal market, Arrowhead Pharmaceuticals is making strides in the treatment of severe hypertriglyceridemia (sHTG). On August 30, the company presented data from its SHASTA-3 and SHASTA-4 Phase 3 trials at the European Society of Cardiology (ESC) Congress 2026 in Munich. The results suggest that plozasiran, an RNAi therapeutic targeting apolipoprotein C-III (APOC3), could fundamentally redefine the standard of care for patients at risk of life-threatening acute pancreatitis.
Severe hypertriglyceridemia is defined by triglyceride levels exceeding 500 mg/dL. Patients with this condition face a significantly elevated risk of acute pancreatitis (AP), a painful and potentially fatal inflammation of the pancreas. Current treatments, including fibrates and high-dose omega-3 fatty acids, often provide insufficient reduction for the most severe cases.
The SHASTA trials evaluated a 25 mg dose of plozasiran administered subcutaneously once every three months. The primary and secondary endpoints were met with high statistical significance. In SHASTA-3 and SHASTA-4, median triglyceride reductions from baseline were 79% and 81%, respectively, at the 12-month mark. Perhaps most importantly for clinical practice, over 90% of patients treated with plozasiran achieved triglyceride levels below the 500 mg/dL threshold, and more than half saw their levels drop into the normal range (below 150 mg/dL).
Impact on Acute Pancreatitis and Safety Profiles
A prespecified pooled analysis of the SHASTA data revealed a profound impact on the incidence of acute pancreatitis. Plozasiran reduced the rate of all AP events by 78% compared to the placebo group. For a specific high-risk subgroup—those with a prior history of pancreatitis and baseline triglycerides above 500 mg/dL—the results were even more striking, showing a 91% reduction in event rates. The "number needed to treat" (NNT) to prevent one episode of acute pancreatitis over one year was calculated at just 24 for the broad population and a remarkably low 3 for the high-risk subgroup.
Dr. James Hamilton, Chief Medical Officer at Arrowhead, noted that the reduction in AP events became increasingly meaningful as the patient’s baseline risk increased. This suggests that plozasiran could serve as a preventative cornerstone for the most vulnerable metabolic patients.
From a safety perspective, the SHASTA trials reported that treatment-emergent adverse events (TEAEs) were balanced between the plozasiran and placebo groups (73% for both). However, there was a noted imbalance in glycemic control, with 14.3% of plozasiran patients reporting worsening glycemic control compared to 8.7% in the placebo group. Despite this, researchers observed that mean HbA1c levels remained relatively stable over time, suggesting the clinical impact on diabetes management may be manageable. No significant concerns regarding liver enzymes or platelet counts were identified, which is a critical observation for the RNAi class of drugs.
Future Outlook and Regulatory Chronology
The timeline for these therapies indicates a busy 2026 for regulatory agencies. Arrowhead Pharmaceuticals has already purchased an FDA Priority Review Voucher, which they intend to use for a supplemental New Drug Application (sNDA) for plozasiran before the end of 2026. This move is expected to accelerate the review process, potentially bringing the drug to market by mid-2027. The company plans to seek marketing authorization globally, leveraging data not only from the SHASTA trials but also from the MUIR-3 study.
For Bayer, the immediate focus remains the integration of KERENDIA into clinical guidelines for type 1 diabetes. Medical societies, including the American Diabetes Association (ADA) and the Kidney Disease: Improving Global Outcomes (KDIGO) organization, frequently update their recommendations following such landmark FDA approvals. The inclusion of finerenone as a standard of care for T1D patients with albuminuria is expected to occur in the next revision cycle.
The broader implications of these developments point toward a new era of "organ-protective" medicine. Whether through the selective antagonism of mineralocorticoid receptors or the silencing of specific genes involved in lipid metabolism, the goal of pharmaceutical innovation is shifting from symptom management to the long-term preservation of organ function. For the millions of adults living with type 1 diabetes and severe lipid disorders, these breakthroughs offer a reprieve from the chronic anxiety of impending organ failure or acute medical crises.
