LONG-TERM CYCLOSPORINE-A PHARMACOKINETIC PROFILES IN PEDIATRIC RENAL-TRANSPLANT RECIPIENTS

To study the long-term effect of cyclosporin A (CyA), 94 6-h and 29 12 -h pharmacokinetic profiles were evaluated in 32 children at least 1 y ear after renal transplantation. Children weighing less than 25 kg nee ded significantly higher doses of CyA than those weighing more than 25 kg(9.8 vs 5.3 mg/kg per day; P < 0.001) to achieve similar trough lev els (TL). The average dose of CyA required to achieve the target TL de clined gradually with time after transplantation. The average area und er the curve over 6 h (AUC/6) correlated strongly with the AUC/12 (r = 0.967, P < 0.001). The AUC/6 of patients with biopsy-proven CyA toxic ity was significantly higher than for those without, toxicity (Mann-Wh itney U-test P < 0.05) despite similar TL. We conclude that AUC monito ring for 6 h provides valuable information not only on TL but also on the absorption and elimination characteristics of CyA as well as on th e potential for CyA toxicity.