Current Bioanalysis of Molecularly Targeted Drugs Using Liquid Chromatography-Tandem Mass Spectrometry

Molecularly targeted drugs (MTDs), such as tyrosine kinase inhibitors, have been actively developed and widely used in recent years due to their high selectivity and therapeutic efficacy compared to conventional cytotoxic chemotherapeutic agents. Bioanalysis of MTDs for therapeutic drug monitoring (TDM) is performed by many medical and clinical laboratories, and the implementation of TDM for MTDs can lead to better control of tumor progression, reduce tumor recurrence, and minimize side effects. Since bioanalysis of MTDs often requires high detection sensitivity with a limit of quantitation of 1 ng/mL or less, many of the reported analytical methods are performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This review highlights recent bioanalytical methods for MTDs using LC-MS/MS. We selected articles on bioanalysis of MTDs of signal transduction inhibitors that (1) were published after 2017, (2) used human samples (whole blood, plasma, serum, urine), and (3) underwent analytical validation. Typical analytical conditions, notable pretreatment techniques, LC separations, and measurement techniques are outlined.