Development and validation of a liquid chromatography tandem mass spectrometry assay for the quantitation of a protein therapeutic in cynomolgus monkey serum.

•A bioanalytical method for a protein drug candidate using LC-MS/MS was fully validated.•The method adopted a recently reported albumin removal approach to simplify sample preparation process.•Advantages of using the albumin removal step were investigated.•The method was used in a toxicology study and results were comparable to data generated using a traditional immunoassay.•LC-MS/MS was demonstrated to be a good complementary tool for protein bioanalysis.