Comparison of three methods for cyclosporine therapeutic monitoring.

Cyclosporine (CsA) is an immunosuppressive drug used extensively in human transplants of solid organs or bone marrow as well as in the treatment of autoimmune diseases. To optimize immunosuppressive efficacy and minimize adverse reactions, blood CsA concentrations are monitored to allow appropriate dosage adjustments. To establish objective criteria to compare various techniques of CsA monitoring, we performed a detailed study over 5 months to compare and evaluate three immunoassays methods in comparison to the reference method of high-performance liquid chromatography (HPLC). Our study included 976 samples that were evaluated by: the COBAS INTEGRA 800 (Roche Laboratories); the V-Twin (Dade Behring Laboratories); and the AxSYM FPIA (Abbott Laboratories). Our results showed that all of the immunoassays yielded slightly higher concentrations than HPLC. However CsA concentrations obtained by AxSYM were most close to those of HPLC, so that this method seemed to be more specific than the other two.