Analytical and Measuring Instruments for immunosuppressive drugs

Abstract

It is well acknowledged that adequate dosage adjustment of immunosuppressive drugs is essential for the graft survival after organ transplantation. Therefore, it is necessary to monitor the pharmacokinetics, efficacy and adverse reactions of immunosuppressive drugs. Therapeutic drug monitoring(TDM)is a methodology of measurement of blood concentration of drugs and their metabolites, and is evaluated as to be a useful technology maintaining the blood level of immunosuppressive drugs within the narrow therapeutic range. In clinical daily TDM, several methodologies to measure the blood levels of cyclosporine, tacrolimus, mycophenolate mofetil, and everolimus are available in Japan. Most of measurement methodologies of immunosupressive drugs are the indirect-immunoassay with the specific monoclonal antibodies against drugs with their unique instruments. However, we should pay attention to cross-reactivity of each monoclonal antibody with some metabolites of immunosuppressive drugs to avoid overestimation of the measurement data of blood concentration. Therefore, the target concentration range of each drug should be determined for each assay system.