Two‐hour post‐dose cyclosporine level is a better predictor than trough level of acute rejection of renal allografts

Pescovitz, MD, Barbeito, R for the Simulect US01 Study Group. Two‐hour post dose cyclosporin level is a better predictor than trough level of acute rejection of renal allografts. Clin Transplant 2002: 16: 378–382. © Blackwell Munksgaard, 2002 Cyclosporine (CyA) trough concentrations are poor predictors for acute rejection post‐transplant. Patients were part of a randomized trial of basiliximab (n=70) vs. anti‐thymocyte globulin (ATGAM) (n=65), both in combination with Neoral, mycophenolate mofetil, and steroids, undergoing first or second, cadaveric or live donor renal transplants. Whole blood samples were collected just before (C0) and at 2 h after CyA dosing on day 4 and at the end of weeks 1, 2, 4, and 8. The CyA was measured by florescence polarization immunoassay (TDx). Mean CyAC0andC2concentrations were calculated. Logistic regression analysis revealed that meanC2level was the only predictor of acute rejection (P ≤ 0.001). Higher meanC2levels predicted lower rejection probabilities. Linear regression analysis revealed that higher meanC2levels were not related to higher serum creatinine levels at either week 4 or 24 or to incidence of headache or tremor. The CyAC2levels predict the frequency of rejection postrenal transplant. TargetC2levels are in the range of 1500 ng/dL.