Immune Monitoring to Facilitate Belatacept Monotherapy

Immune Monitoring to Facilitate Belatacept Monotherapy

• To determine the utility of novel blood-based immune monitoring tools (Allosure and Trugraf) to facilitate belatacept monotherapy.
• To determine the percent of belatacept-treated renal transplant patients that can be safely converted to belatacept monotherapy.

This study will examine whether renal transplant recipients treated with a belatacept-based immunosuppressive regimen can safely be weaned off all non-belatacept immunosuppression (mycophenolate, mTORi, prednisone) in a stepwise fashion. To this end, participants will undergo monthly "immune monitoring" using the Allosure (dd-cfDNA) and Trugraf (RNA profiling) blood tests to determine if they are in a state of immune quiescence. Only patients who are deemed to be immune quiescent, will continue to be weaned of non-belatacept immunosuppression.

Inclusion Criteria:

• Age minimum 18 years
• Written informed consent
• Single kidney transplant recipient (i.e. no combined organ transplants)
• Treated with de novo belatacept since transplantation (i.e. no previous use of calcineurin inhibitor or mTOR inhibitor for the current transplant)
• At least 1 year after transplantation or after initiation of belatacept
• Stable renal function (eGFR > 40 ml/min continuously during previous 6 months)
• Blood biomarkers indicate immune quiescence (for Allosure this corresponds to dd-cfDNA < 1%; for Trugraf this corresponds to "TX" signature)
• No history of BK viremia in current allograft

Exclusion Criteria:

• History of biopsy-proven acute rejection
• Presence of donor-specific antibodies (at any MFI)
• Spot urine protein/creatinine ratio > 0.5 g/g