Early Conversion to Belatacept in Kidney Transplant Recipient with Low Glomerular Filtration Rate

BACKGROUNDOur aim was to determine the impact of converting from tacrolimus to belatacept in patients with stable low eGFR early after kidney transplant. METHODSThis is a single center retrospective case control study. During this study period we had a clinical protocol to convert patients to belatacept if they had a stable but low GFR and they were at least 1-month posttransplant. Eligible patients had stable but low eGFR usually < 40 ml/min/1.73m2. We used direct matching to select 1 control case for each patient converted to belatacept. The primary outcome was the change in eGFR from the point of belatacept conversion to 4 months post conversion (delta eGFR). RESULTSThere were 30 patients in the conversion group and 30 in a direct matched control group. The median preconversion eGFR for the entire cohort was 23.0 ml/min/1.73 m2 with an IQR of 15.7 to 31.4. The delta eGFR was 11.0 (12.9) ml/min/1.73m2 in belatacept group and 4.8 (10.5) ml/min/1.73m2 in the control group (p=0.045). Acute rejection postconversion occurred in 5 (16.7%) in the conversion group and none of the control group (p=0.052). While the delta improvement in eGFR was about 6 ml/min better in the Belatacept group, there was no difference in the slope of inverse creatinine during the 12-month period after conversion between the groups. CONCLUSIONWe conclude that early belatacept conversion in kidney transplant recipients with stable low eGFR may only result in a modest increase in GFR.