Kidney Week

Abstract: TH-PO0520

Layered Precision Therapy for Advanced IgAN Beyond Trial Eligibility: Thirteen-Month Real-World Experience with Targeted-Release Formulation (TRF)-Budesonide and Atrasentan

Session Information

• Glomerular Diseases: IgAN, IgA Vasculitis, and More
  October 22, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Gau, Tyng-shiuan, Renal Division, Department of Internal Medicine, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan

Tyng-shiuan Gau, MD

• Chang, Fan-Chi, Renal Division, Department of Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan

Fan-Chi Chang, MD, PhD

Group or Team Name

• Taiwan Glomerular Consortium (TGC)

Introduction

Patients with IgA nephropathy (IgAN) and eGFR <30 mL/min/1.73m² are excluded from landmark trials of TRF-budesonide and atrasentan. Real-world safety and efficacy data in this population are lacking. We report 13-month outcomes of combination therapy in a patient with advanced IgAN beyond conventional trial criteria.

Case Description

A 48-year-old woman presented with progressive IgAN (eGFR 28.8 mL/min/1.73m², UPCR 1.95 g/g) despite long-term ARB and prednisolone 5mg daily. SGLT2 inhibition was initiated, reducing UPCR to ~1.0 g/g. Kidney biopsy confirmed IgAN with Oxford MEST-C M0E0S1T1C0, >60% global glomerulosclerosis, tubular atrophy 30%, and interstitial fibrosis 45–50%. Estimated 5-year risk of ESKD was 51.6%. Given residual proteinuria and ineligibility for clinical trials, TRF-budesonide 8mg daily was initiated (reduced dose given concurrent low-dose corticosteroid and body weight), followed by atrasentan 0.75mg 17 days later. A transient eGFR dip occurred (nadir 23.3), resolving spontaneously. Over 13 months, UPCR declined from 1.27 to 0.40–0.66 g/g and eGFR stabilized at 24–27 (Table 1). Both agents were well tolerated with no major adverse events. Prednisolone was tapered to 5mg every other day at month 13.

Discussion

This case demonstrates feasibility and sustained clinical benefit of combination TRF-budesonide and atrasentan in a patient with advanced IgAN excluded from major trials. The 13-month follow-up confirms durable proteinuria reduction and eGFR stabilization despite chronic histologic injury. The transient eGFR dip with atrasentan resolved without intervention, providing important safety data with eGFR <30. Individualized dosing of TRF-budesonide and ongoing low-dose corticosteroid tapering reflect real-world complexity absent from trial protocols. These findings support cautious extension of layered precision therapy to advanced IgAN and underscore the need for prospective studies in this high-risk, underserved population.

Acknowledgment

We thank the staff of the Seventh Core Lab, Department of Medical Research, National Taiwan Univeristy Hospital for technical support. Atrasentan was provided under the Novartis Managed Access Program.