Determination of ticagrelor and two metabolites in plasma samples by liquid chromatography and mass spectrometry.

Rapid and sensitive analytical methods using liquid chromatography with tandem mass spectrometry (LC/MS/MS) were developed for the determination of ticagrelor, the first reversible oral platelet P2Y(12) receptor inhibitor, and its metabolites AR-C124910XX and AR-C133913XX in human plasma. Ticagrelor and its metabolites were extracted using protein precipitation with acetonitrile. Chromatographic separations were performed on reversed phase columns and detection using atmospheric pressure chemical ionization (APCI). Ticagrelor and AR-C124910XX were analyzed in the same assay, with the internal standard, d7-ZD6140, on a C18 column using negative ionization; AR-C133913XX analyzed separately on a phenyl column using positive ionization. Full validation of the methods was performed including selectivity, lower limit of quantification, accuracy, precision stability and incurred sample reproducibility and incurred sample stability. Total analytical run time was short (2 min). Calibration curves were established in the range 5-5000ng/mL for ticagrelor, 2.5-2500 ng/mL for AR-C124910XX and 2-1000 ng/mL for AR-C133913XX. Lower limits of quantification for ticagrelor, AR-C124910XX and AR-C133913XX were determined to be 5, 2.5 and 2.0 ng/mL, respectively from 100 microL of human plasma. For ticagrelor, AR-C124910XX and AR-C133913XX, mean intra-batch accuracy was 91.9-109.0%, 86.8-109.2% and 100.5-112.0%, respectively; intra-batch precision was 4.0-8.4%, 5.2-16.9% and 3.9-12.3%, respectively. The methods were also applied to quantification of ticagrelor, AR-C124910XX and AR-C133913XX in rabbit, rat, mouse and marmoset, using 25 microL of animal plasma. A modified methodology was developed to quantify ticagrelor and AR-C124910XX in plasma from dog and cynomolgus monkey. Human incurred samples were found to generate consistent reproducibility and stability results. This method was successfully applied to determine plasma concentrations following administration of ticagrelor in human volunteers and patients, and animal safety evaluation studies. This validated methods has the advantages of being straightforward, robust and allows a fast throughput of samples. 2010 Elsevier B.V. All rights reserved.