A new reliable, transposable and cost-effective assay for absolute quantification of total plasmatic bevacizumab by LC-MS/MS in human plasma comparing two internal standard calibration approaches

This study demonstrates the importance of the choice of the IS in quantifying bevacizumab in human plasma and highlights the difficulty of reaching a reliable proteolysis with a sufficient recovery. We developed a reliable and cost-effective LC-MS/MS method to quantify total plasmatic fraction of bevacizumab in human plasma. Through our development we proposed a generic methodology easily transposable to quantify all IgG1 subclass very useful for clinical pharmacokinetics studies.