Renal function outcomes in kidney transplant recipients after conversion to everolimus-based immunosuppression regimen with CNI reduction or elimination.

BACKGROUND: Chronic allograft nephropathy (CAN) is a major cause of progressive renal failure in kidney transplant recipients. Its etiology is multifactorial and can be due to immunologic or nonimmunologic conditions including calcineurin inhibitor (CNI) toxicity.

OBJECTIVE: To evaluate the effect of conversion from CNIs to everolimus in kidney transplant recipients with CAN.

PATIENTS AND METHODS: In this 12-month pilot study in renal transplant recipients with biopsy-proved CAN, therapy was changed to an everolimus-based immunosuppression regimen. Cyclosporine or tacrolimus dosage was reduced by 80% (group 1, n = 10) or discontinued (group 2, n = 10). Mycophenolate mofetil or azathioprine were withdrawn in group 1, whereas both agents were maintained in group 2. All patients received prednisone.

RESULTS: Twenty renal allograft recipients switched to an everolimus-based regimen, and patients were followed up for a mean (SD) of 12 (0.1) months. Baseline and end-of-study data were as follows: serum creatinine concentration, 1.27 (0.35) mg/dL vs 1.24 (0.4) mg/dL in group 1, and 1.27 mg/dL (0.36) vs 1.25 (0.3) mg/dL in group 2 (difference not significant); and estimated glomerular filtration rate, 72.4 (19.86) mL/min vs 76.26 (22.69) mL/min in group 1 (not significant), and 66.2 (12.95) mL/min vs 66.2 (13.73) mL/min in group 2 (not significant). One patient in group 1 experienced an acute rejection episode (Banff grade Ib), and 2 patients in group 1 and 1 patient in group 2 demonstrated borderline changes, all associated with everolimus blood concentration less than 3 ng/mL.

CONCLUSIONS: Reduction or withdrawal of CNI and introduction of everolimus may be useful to slow the rate of loss of renal function in patients with CAN.