Basiliximab lowers the cyclosporine therapeutic threshold in the early post-kidney transplant period

Early adequate cyclosporine exposure has been shown to predict low acute rejection rate in kidney transplantation. The aim of this study is to determine the importance of exceeding the early cyclosporine therapeutic exposure threshold with basiliximab induction. A retrospective analysis of 166 first cadaveric and non-identical live donor transplant recipients treated with or without basiliximab induction, Neoral, mycophenolate mofetil and prednisone, was performed. Adequate exposure was defined as a 2-h post-Neoral dose cyclosporine level (C2) > 1700 ng/mL at day 3. The primary outcome was acute rejection within the first 6 months. In the no basiliximab (control) group (n = 74), rejection occurred in 23% (17 of 74) of recipients and was strongly associated with low cyclosporine exposure on day 3. Acute rejection occurred in 38% (11 of 29) with C2 < 1700 ng/mL compared with 13% (six of 45) with C2 ≥ 1700 ng/mL (p = 0.014). In the basiliximab group (n = 92), rejection occurred in only 11% (10 of 92) of recipients and did not correlate with cyclosporine exposure. Acute rejection occurred in 10% (four of 40) with C2 <1700 ng/mL compared with 12% (six of 52) with C2 ≥ 1700 ng/mL (p = 0.81). Therefore achieving cyclosporine therapeutic targets by day 3 may not be required when anti-IL2 receptor antibody induction is used.