A randomized trial comparing renal function in older kidney transplant patients following delayed versus immediate tacrolimus administration

Abstract

Background: This large, randomized, multicenter trial evaluated if basiliximab induction and delayed tacrolimus can preserve renal function in older kidney transplant patients.

Methods: Patients aged 60 years and older received delayed tacrolimus with basiliximab and mycophenolate mofetil with early steroid discontinuation (Tac-d, n=132) or standard tacrolimus with mycophenolate mofetil and steroids until day 91 (Tac-s, n=122). Tacrolimus trough levels were 5 to 10 ng/mL after day 43 in both groups. Renal function at month 6 was measured by calculated creatinine clearance (Cockcroft-Gault formula).

Results: In both groups, mean recipient age was 66 years, mean donor age was 63 years with 73% of donors aged 60 years and older. Steroid discontinuation was slower than protocol specified. In the Tac-d group, 56.1% were steroid free at day 14 and 81.8% at month 6. In the Tac-s group, 37.7% were steroid free at month 4 and 63.9% at month 6. Mean (+/-SD) calculated creatinine clearance was 45.7+/-16.1 mL/min (Tac-d) and 45.0+/-18.2 mL/min (Tac-s) (P=ns), mean glomerular filtration rate (modified diet in renal disease formula) was 44.9+/-16.2 mL/min and 41.6+/-16.8 mL/min, respectively. Incidences of biopsy-proven acute rejection were 18.9% (Tac-d) and 18.0% (Tac-s). Delayed graft function was 30.3% (Tac-d) and 23.8% (Tac-s). Estimated patient survival rates (Kaplan-Meier) in the Tac-d and Tac-s groups were 96.1% vs. 99.2% and estimated graft survival rates were 90% vs. 87.6%, respectively. Safety results were similar with both regimens.

Conclusion: Delayed tacrolimus with basiliximab induction did not provide an advantage in preserving renal function or reducing delayed graft function in older kidney transplant patients.