Kidney Week

Abstract: PO2126

Belatacept Conversion in Proteinuric Kidney Transplant Recipients: Data from a Retrospective Cohort and a Prospective Trial

Session Information

• Transplantation: Clinical - Underrecognized Risk Factors, Traditional Considerations, and Outcomes
  November 04, 2021 | Location: On-Demand, Virtual Only
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 1902 Transplantation: Clinical

Authors

• Efe, Orhan, Massachusetts General Hospital, Boston, Massachusetts, United States

Orhan Efe, MD

• Al Jurdi, Ayman, Massachusetts General Hospital, Boston, Massachusetts, United States

Ayman Al Jurdi,

• Wojciechowski, David, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

David Wojciechowski,

• Safa, Kassem, Massachusetts General Hospital, Boston, Massachusetts, United States

Kassem Safa,

• Gilligan, Hannah M., Massachusetts General Hospital, Boston, Massachusetts, United States

Hannah M. Gilligan,

• Chandraker, Anil K., Brigham and Women's Hospital, Boston, Massachusetts, United States

Anil K. Chandraker,

• Azzi, Jamil R., Brigham and Women's Hospital, Boston, Massachusetts, United States

Jamil R. Azzi,

• Weins, Astrid, Brigham and Women's Hospital, Boston, Massachusetts, United States

Astrid Weins,

• Riella, Leonardo V., Massachusetts General Hospital, Boston, Massachusetts, United States

Leonardo V. Riella,

Background

Proteinuria is a strong predictor of graft loss in kidney transplant (KT) patients. Treatment options for proteinuria are limited to ACEis/ARBs. Belatacept targets B7-1 which is also expressed on podocytes and has been linked to proteinuria by inducing podocyte migration. We examined the utility of belatacept conversion in proteinuric KT recipients.

Methods

In the phase I multicenter trial, we recruited EBV IgG+ adult KT recipients > 6 months post-KT with an eGFR > 30ml/min/1.73m², proteinuria > 1g/day on CNI-based immunosuppression. Patients were converted from CNI to belatacept. The primary outcome was 25% reduction in proteinuria at 12 months. In the retrospective cohort, we included patients who were converted to belatacept in 2015-2019.

Results

In the retrospective cohort, 12 of 77 belatacept conversion patients had pre-conversion proteinuria > 0.4 g/g and follow up values. Baseline proteinuria decreased from 1+0.9 g/g to 0.69+0.9 g/g at >12 months (p=0.070). Mean eGFR increased from 37+12 to 49+15 ml/min/1.73m² at 12 months. In the prospective cohort, 15 KT recipients were recruited. At 12 months post-conversion, mean (+SD) eGFR remained stable at 43.7±12.9 ml/min/1.73m² and proteinuria improved from 2.5+1.9 to 1.7±1.8 g/g (p=0.068). Primary outcome was reached in 53% of the patients. None of the patients had graft rejection in the first year. One patient had worsening of proteinuria and discontinued belatacept. At 24 months, eGFR remained stable and proteinuria was 1.4+1.2 g/g. Figure 1 summarizes eGFR and proteinuria course from both cohorts.

Conclusion

Belatacept conversion in proteinuric KT recipients was associated with stable allograft function and reduction in proteinuria at 1 year and beyond.

Funding

• Commercial Support –