Kidney Week

Abstract: TH-PO1226

Molecular Diagnostics to Facilitate Belatacept Monotherapy in Kidney Transplant Recipients

Session Information

• Late-Breaking Research Posters
  November 06, 2025 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2102 Transplantation: Clinical

Authors

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

David Wojciechowski, DO

• Feizpour, Cyrus, Medical University of South Carolina, Charleston, South Carolina, United States

Cyrus Feizpour, MD

• Marsh, Morgan, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Morgan Marsh

• Han, Hwarang Stephen, The University of Texas at Austin, Austin, Texas, United States

Hwarang Stephen Han, DO

• Levea, Swee-Ling, The University of Texas Southwestern Medical Center, Dallas, Texas, United States

Swee-Ling Levea, MD

• Salcedo Betancourt, Juan David, Penn Medicine, Philadelphia, Pennsylvania, United States

Juan David Salcedo Betancourt, MD, FASN

Background

The molecular diagnostic tests donor-derived cell free DNA (dd-cfDNA; AlloSure) and gene expression profiling (AlloMap) have demonstrated a high negative predictive value ruling out antibody and sub-clinical T cell rejection, respectively. They have not been evaluated to guide immunosuppression (IS) management. We aimed to investigate their utility in weaning IS in kidney transplant recipients (KTR) on a belatacept-based regimen to achieve belatacept monotherapy (NCT04786067).

Methods

We conducted a prospective, single-center observational study enrolling adult KTR who were at least 1-year post-transplant and maintained on belatacept-based IS. Inclusion criteria: eGFR ≥ 40 mL/min/1.73 m2, absence of donor-specific antibodies (DSA), no prior history of rejection, and spot urine protein:creatinine (UPCR) <1 g/g. AlloSure (normal ≤1%), AlloMap (normal ≤11.5), serum creatinine, UPCR, and DSA were measured monthly for 3 months to confirm stability and an additional 12 months for protocol guided IS weaning.

Results

24 subjects were analyzed for a 15 month period. Mean age was 54.8 years and mean 860 days post-transplant at enrollment. The most common regimen used with belatacept was prednisone + mycophenolate (n=16). Mean months 0 and 12 AlloSure results were 0.24% and 0.22%, respectively. Mean months 0 and 12 AlloMap results were 12.22 and 10.78, respectively. Figure 1 demonstrates the change in IS from month 0 to 12. Mean eGFR at months 0 and 12 were 67.7 mL/min/1.73m² and 68.6 mL/min/1.73m², respectively. There was 100% patient and graft survival, with no cases of biopsy-proven rejection, proteinuria or de novo DSA development.

Conclusion

The addition of molecular diagnostic biomarkers facilitated the weaning of IS in 50% of subjects with 16.7% successfully achieving belatacept monotherapy. An additional year of monitoring is ongoing to facilitate further immunosuppression weaning.

Funding

• Commercial Support – CareDx

Digital Object Identifier (DOI)

• doi: 10.1681/ASN.2025a06kx92m