【Objective】 Immunosuppressant drugs such as cyclosporine (CSA), tacrolimus (TAC) and everolimus (EVR) are often used in transplantation therapy. Their concentrations need to be monitored carefully. This study aimed to evaluate the analytical performance of the CLAMTM-2030 connected with LCMSTM-8060 based on the liquid chromatography with tandem mass spectrometry method (LC-MS/MS), which has been newly developed to measure the immunosuppressant drugs in whole blood.
【Methods】 The assay precision, the stability of calibration, linearity, lower limit of quantitation (LOQ), and correlation of immunoassay method with LC-MS/MS were examined using residual whole blood samples from transplantation patients who were being treated with CSA, TAC, or EVR. Furthermore, we measured the metabolites of EVR.
【Results】 The CLAMTM-2030 connected with LCMSTM-8060 showed satisfactorily analytical performance. Regarding the EVR correlation, the difference between two immunoassay methods and LC-MS/MS was revealed (n＝84, r＝0.936, y＝1.172x＋0.799, n＝84，r＝0.979，y＝0.871x−0.661). The result of including the everolimus metabolites was a shift of the correlation slope from 0.871 to 1.026.
【Conclusion】 It is possible to measure CSA, TAC, and EVR simultaneously without pretreatment using CLAMTM-2030 connected with LCMSTM-8060. It may be suitable for routine measuring of immunosuppressant drugs in the clinical laboratory.
