Abstract: FR-PO1162
Sibeprenlimab for IgAN in Kidney Transplant Recipients: A Case Series
Session Information
- Transplantation: Clinical - Transplant Access, Recipient Evaluation, Living Donors, Pregnancy, and More
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Authors
- Sandhu, Sharneet K., Massachusetts General Hospital, Boston, Massachusetts, United States
- Safa, Kassem, Massachusetts General Hospital, Boston, Massachusetts, United States
- Riella, Leonardo V., Massachusetts General Hospital, Boston, Massachusetts, United States
- Al Jurdi, Ayman, Massachusetts General Hospital, Boston, Massachusetts, United States
Background
Recurrent & de novo IgA nephropathy (IgAN) after kidney transplantation increases the risk of allograft dysfunction and loss, with limited management options. Sibeprenlimab selectively binds and inhibits a proliferation-inducing ligand (APRIL), a key driver of IgAN pathogenesis, and reduced proteinuria by ~50% in phase 2 & 3 IgAN trials. We describe early proteinuria outcomes in three kidney transplant recipients with recurrent or de novo IgAN treated with sibeprenlimab.
Methods
Three kidney transplant recipients with biopsy-proven recurrent (n=2) or de novo (n=1) IgAN and persistent proteinuria despite optimized RAS blockade and SGLT2 inhibition received sibeprenlimab 400 mg every 4 weeks. Urine protein-creatinine ratio (UPCR), serum creatinine, and immunoglobulin levels were monitored, and adverse events recorded.
Results
All three patients with IgAN after transplant had stable eGFR and persistent proteinuria despite RAS blockade and SGLT2 inhibition. Following sibeprenlimab initiation, proteinuria declined in all cases. In patient 1, UPCR decreased from 1.5 to 0.46 g/g over 15 weeks; in patient 2, from 2.61 to 1.6 g/g over 13 weeks; and in patient 3, from 1.5 to 0.46 g/g over 9 weeks. These changes correspond to 39-70% reductions in proteinuria (Figure 1). No rejection episodes, BK viremia, or serious infectious complications were observed.
Conclusion
In this early case series, APRIL inhibition with sibeprenlimab was associated with substantial reduction in proteinuria in kidney transplant recipients with recurrent or de novo IgAN, without early safety concerns. These findings suggest APRIL inhibition may represent a promising therapeutic strategy for post-transplant IgAN, a condition with limited targeted treatment options. Larger prospective studies are needed to define long-term safety and efficacy in the allograft setting.