Development of an LC–MS/MS method for quantifying ASK120067, a novel mutant-selective inhibitor of the epidermal growth factor receptor (EGFR) as well as its main metabolite in human plasma and its application in a pharmacokinetic study

•ASK120067 is a third-generation EGFR-TKI for the treatment of NSCLC.•An LC-MS/MS method was developed to detect ASK120067 and its metabolite in plasma.•This method was fully validated from whole blood collection to plasma analysis.•This high-throughput method was rapid in analysis and simple in sample preparation.•This method was applied for a first-in-human clinical trial in Chinese patients.