Optimal C 2 Concentration of Cyclosporin Corrected With Good Efficacy and Safety in Asian Kidney Transplant Recipients

Abstract

Introduction Calcineurin inhibitors (CNI) are known for their renal toxicity. Lower CNI exposure is a reasonable option to mitigate potential CNI-induced renal toxicity. Herein we have presented our long-term results after lower cyclosporine (CsA) exposure in the first year. Materials and Methods Between 1997 and 2004, 63 renal transplant recipients received CsA-based immunosuppression. CsA dosing was adjusted according to the 2-hour whole blood concentration (C 2) level. We retrospectively reviewed acute rejection and graft survivals rates, as well as whole blood C 2 levels. Results Review of serial mean C 2 concentrations at 1, 2, 3, 6, and 12 months after transplantation were 1341, 1241, 1191, 1059, and 927 ng/mL, respectively. These levels were slightly lower than those suggested by the Consensus for C 2 levels by Levy et al in 2002, namely, 1600 to 2000 ng/mL (mean, 1700); 1400 to 1600 ng/mL (mean, 1500); 1200 to 1400 ng/mL (mean, 1300); 1000 to 1200 ng/mL (mean, 1100), and 800 to 1000 ng/mL (mean, 900), respectively. Acute rejection rate at 3 months and 1 year are 17.5% and 23.8%. Graft survival at 1 year was 97% and at 5 years, 89%. Two patient were lost to fulminant hepatitis and acute myocardial infarction during the first year, which were not associated with underimmunosuppression. Conclusion Appropriate CsA C 2 levels may be lower among Taiwanese. Our C 2 dosing strategy resulted in good outcomes with acceptable side effects in our single-center experience. Appropriate CsA C 2 levels for Asians deserve more attention in trials of larger scale; most reference levels are presently concluded from studies of Caucasians.