Important considerations for quantitation of small-molecule biomarkers using LC–MS

“In our opinion, dealing with endogenous levels of the analyte, confirming specificity of the assay, maintaining analyte integrity ex vivo and designing the proper study protocol, comprise the most important aspects of successful biomarker assay development.” In recent years, endogenous molecules, such as catabolic/anabolic products, bioactive small molecules, peptides and proteins, have been increasingly explored and utilized as biomarkers to facilitate drug discovery and development processes [1–4]. Appropriate application of biomarker data in preclinical and clinical studies can enable more predictive and reliable decision making. Activities, such as target and candidate selection, risk assessment, dose escalation, patient stratification, drug–drug interaction...