Analytical performance of the Abbott Architect i2000 tacrolimus assay in Chinese patients after renal transplantation.

Abstract Background Monitoring of tacrolimus concentrations has played a crucial role to control the efficacy versus adverse effects of treatment, because of the drug's narrow therapeutic range, inter- and intraindividual variabilities, and drug interactions mediated by hepatic cytochrome P450. Therefore, the stability of methods to monitor tacrolimus is of major importance. This study evaluated the analytical performance of the Abbott Architect i2000 tacrolimus assay, which was recently released in China to monitor tacrolimus therapy. We compared the results using the Abbott Architect i2000 Tacrolimus assay with the traditional Abbott IMx method. Methods We measured concentrations of tacrolimus in 100 samples from renal transplant patients by Architect i2000 and the commonly used Abbott IMx. Results We observed that the total %CV of the Architect i2000 assay was y = 0.8788 x − 0.3485 with a Spearman correlation coefficient ( r ) of 0.9922. The bias plot between the Architect i2000 and Abbott IMx assay yielded an average negative bias (−1.4 ng/mL). Conclusion We concluded that, because of its high precision and sensitivity, low cross-reactivity, and acceptable accuracy, the Architect i2000 assay is a suitable alternative to monitor tacrolimus concentrations in renal transplant recipients.