Primary immunosuppression with tacrolimus and low-dose mycophenolate mofetil in renal transplant recipients

Both tacrolimus and mycophenolate mofetil (MMF) are potent immunosuppressive agents used in combination for prevention of acute rejection in renal transplantation. We studied the efficacy and safety of tacrolimus/MMF-based primary immunosuppression as well as their pharmacokinetics (PK) in Chinese renal transplant recipients. Oral tacrolimus was initiated at about 0.2 mg/kg/d, dose which was adjusted to achieve target trough levels of 10 to 20 ng/mL at 3 months and 5 to 10 ng/mL thereafter. The patients also received MMF (0.5 g bid) and prednisolone. PK profiles were studied at 1 week, and 1, 3, and 6 months posttransplant. Blood samples were taken at 0 (predose), 20, 40, 60, 75, and 90 minutes and 2, 4, 6, 8, 10, and 12 hours postdose for each profile. Plasma MPA and whole blood tacrolimus levels were determined by HPLC and EMIT methods respectively. Eight patients were studied with mean follow-up of 16.1 +/- 2.4 months. One patient (12.5%) experienced a borderline acute rejection episode. Both 1-year graft and patient survival rates were 100%. Posttransplant diabetes, diarrhea, and hand tremor occurred in 12.5%, 12.5%, and 37.5%, respectively. No patient had an opportunistic infection. Tacrolimus trough concentrations showed a fair correlation with AUC(0-12h) (R(2) = 0.587). Mean MPA AUC values at 1, 3, and 6 months were 40.5 +/- 9.4, 44.4 +/- 17.3, and 57.2 +/- 20.7 mug*h/mL, respectively (P = .0486, n = 7). In conclusion, primary immunosuppression with tacrolimus, low-dose MMF (0.5 g bid), and prednisolone is effective and safe with adequate systemic MPA exposure in renal transplant recipients.