CX1003 quantification by ultra-performance LC-MS/MS in human plasma and its application to a pharmacokinetic study in solid tumor patients.

CX1003 is a novel multitargeted receptor tyrosine kinase inhibitor targeting cancer patients with relapsed or metastatic malignant solid tumors. The study aimed to develop a robust and rapid assay approach to quantify CX1003 in human plasma. Samples of plasma were purified by SPE where the diluted eluates were then separated by a Waters Acquity CSH C column and thereafter detected using positive electrospray ionization via an ultra performance LC-MS/MS. The method to quantify CX1003 in human plasma was first exploited and validated with good sensitivity and specificity, and successfully fulfilled the requirement of the first-in-human clinical pharmacokinetic study of CX1003 in Chinese patients with relapsed or metastatic malignant solid tumors.