551 - Belatacept Use in Pediatric Kidney Transplant Recipients: A Single-Center Case Series

Publication Number: 4539.551

Shivani P. Wadnerkar, Children's Mercy Hospitals and Clinics, Mission, KS, United States; Jeffrey Saland, The Mount Sinai Kravis Children's Hospital, New York, NY, United States; Ron Shapiro, Recanati/Miller Transplant Institute, New York, NY, United States

Background: Belatacept, a T cell co-stimulation blocker, has emerged as a potential alternative to calcineurin inhibitors (CNI) for immunosuppression in kidney transplantation. While extensively studied and FDA approved in adults, data on its efficacy and safety in pediatrics remains limited. This study describes a single-center experience with Belatacept use in pediatric kidney transplant patients.

Objective: Our study aims to describe the clinical experience with conversion to Belatacept for maintenance immunosuppression in pediatric kidney transplant recipients.

Design/Methods: A retrospective review was conducted on pediatric kidney transplant recipients who were converted to Belatacept-based immunosuppression between 2014 - 2024. This study was approved by the IRB in accordance with institutional ethical guidelines. Patient demographics, transplant history, immunosuppression regimen, reason for conversion, rejection episodes, and adverse events were analyzed. Graft function was assessed at 1, 3, 6, and 12 months post-Belatacept conversion.

Results: A total of 7 patients with median age 8 years at the time of ESKD diagnosis were included. All these patients were EBV seropositive at the time of conversion to Belatacept. The most common indications for conversion to Belatacept were non- adherence to immunosuppression, followed by CNI toxicity. Patients received Belatacept infusions every four weeks at an outpatient infusion center, while one patient was able to receive her monthly infusion at home. All patients were continued on Mycophenolate mofetil with or without steroids and CNIs were discontinued in six patients while one was maintained on a low dose. In the 12 month follow up period, new acute cellular rejection occurred in two patients. None developed positive donor specific HLA antibodies post conversion. There was no incidence of BK viremia or CMV infection in this group in the 12 month follow up period. Six out of seven had a median eGFR decline ~ 5.5 ml/min/1.73 m2 at 1 year post conversion mark and the seventh patient lost their graft before the 1-year mark. The only indication for discontinuation of Belatacept was graft failure within the follow up period and initiation of hemodialysis.

Conclusion(s): Belatacept conversion in pediatric kidney transplant recipients was associated with stable graft function in most patients and may serve as a viable alternative to CNIs. However, cellular rejection remains a concern. Larger prospective studies are needed to further evaluate the long-term outcomes, considerations for early conversion and safety profile of Belatacept in pediatric kidney transplantation.

Mechanism of action of Belatacept
APC: Antigen Presenting Cell, MHC: Major Histocompatibility Complex, TCR: T Cell Receptor
PMID: 33816147

Graft function and outcomes