Abstract: AIM: To develop an LC/MS/MS meth-od for the determination of icotinib in dog plasma and study the pharmacokinetics of icotinib.METHODS: Icotinib was administered to 32 Beagle dogsvia intrave-nous bolus (10 mg/kg) or oral dosing (10, 20 or 40 mg/kg) administration after randomly dividing into 4 groups.The concentrations of icotinib in dog plasma were detected by using LC/MS/MS method, and the pharmacokinetic parameters were calculated.RESULTS: The linear calibration curves were obtained in the concentration range of 0.5 -10000 ng/mL .The relative standard deviation (RSD) of intra-day and in-ter-day was less than 10%.The value of area under the curve (AUC_0-t ) was (27.3 ±15.3) μg^。mL^-1。h after intravenous bolus administration.The values of AUC_0-t were (7.47 ±3.30) , (23.5 ±11.5) and (54.5 ±24.9) μg^。mL^-1。h after oral dosing for the three groups, respectively .The absolute bioavailability of icotinib in dog was 27.4%.CONCLUSION: The method is sensitive, selective and proved to be suitable for preclinical investigation of icotinib pharmacokinet-ics.

Key words: icotinib, pharmacokinetics, LC/MS/MS, Beagle dog