Bioanalytical methods for therapeutic monoclonal antibodies and antibody-drug conjugates: A review of recent advances and future perspectives.

As the use and development of therapeutic monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs) increases, the need for accurate and robust bioanalytical methods is also increasing. Up to about a decade ago, bioanalysis of therapeutic mAbs was performed only by ligand-binding assay (LBA), and this was the only available method for absolute quantitation. Recent technological advances in liquid chromatography (LC)-tandem mass spectrometry (LC-MS/MS) and LC-high-resolution mass spectrometry can realize specific, accurate, and multiplex bioanalysis of these with a wide dynamic detection range. In this review, we introduce recent analytical techniques in bioanalytical methods for therapeutic mAbs and ADCs using LC-MS with three (bottom-up, top-down, and middle-down) proteomics strategies from the viewpoint of improving detection sensitivity, assay accuracy, and selectivity.