Abstract: Rituximab is the main monoclonal antibody for targeted therapy currently. With more rituximab biosimilars appearing and clinical evaluation need increasing, it is crucial to develop rapid and effective quantitative methods to determine the rituximab blood concentration in biological matrices for drug metabolism and pharmacokinetics (DMPK) analysis. This article reviewed the application of ligand binding method (LBA), liquid chromatography-tandem mass spectrometry (LC-MS/MS) and emerging quantitative technology to detect the blood concentration of Rituximab, which may provide valuable information for the analysts and testers when developing quantitative methods for rituximab and its biosimilars.

Key words: rituximab, biosimilar, LBA, LC-MS/MS, immunogenicity