This is a report of cyclosporine (CYA) therapy with trough level monitoring in whole blood and individual pharmacokinetic studies by high-performance liquid chromatography (HPLC) and fluorescence polarization immunoassay (FPIA) in 19 renal transplant recipients. The correlation coefficient for the values obtained by HPLC and FPIA was 0.90. However, the values with FPIA based on polyclonal antibodies were approximately twice those with the HPLC method. The patients were given two equal doses (8: 00 am, 8: 00 pm) of CYA orally. The morning trough level/night trough level (M/N) ratio of CYA with the initial dose was significatly higher than that of the maintenance dose (HPLC, P<0.05 ; FPIA, P<0. 001). In the individual pharmacokinetic studies in 4 patients, the Cmax and AUC following the night CYA dose were smaller than with the morning dose in all patients.
