Background: To reduce long-term nephrotoxic calcineurin inhibitor dosage, adjunctive sirolimus or mycophenolate mofetil (MMF) was used in a 150-patient, randomized, three-armed trial in cadaveric or human leukocyte antigen non-identical living-donor first renal transplant recipients (n=50/group).
Methods: Group A received tacrolimus and sirolimus. Target tacrolimus trough levels postoperatively were 10, 8, and 6 ng/mL at 1 month, 6 months, and 1 year, respectively. Group B received tacrolimus and MMF. Target tacrolimus trough levels were 10 and 8 ng/mL at 1 month and 1 year, with a targeted dose of MMF of 1 g twice daily. Group C received cyclosporine A (CsA) (Neoral, Novartis, Basel, Switzerland) and sirolimus with target CsA trough levels of 225 and 175 ng/mL at 1 month and 1 year. Maintenance sirolimus target trough levels were 8 ng/mL in groups A and C. Each group received daclizumab induction and methylprednisolone maintenance. This first of two companion 1-year reports details demographics, drug-dosing interactions, and rejection.
Results: There were no notable differences in group demographics, but a somewhat less favorable course occurred in group C, despite higher bioavailability of sirolimus in group C versus group A (P<0.001). Acute rejection rates were lower in groups A (4%) and B (4%) combined versus group C (14%) (P=0.03). Histopathologic findings were supported by comparing perioperative with 1-year postoperative protocol biopsies.
Conclusions: This 1-year interim analysis indicates that a decreasing dosage of tacrolimus with either adjunctive sirolimus or MMF may optimize future graft survival versus a less favorable outcome using a similar algorithm with CsA and sirolimus.