LC/MS/MS Bioanalysis of Protein–Drug Conjugates—The Importance of Incorporating Succinimide Hydrolysis Products

Bioanalysis of antibody–drug conjugates (ADCs) is challenging due to the complex, heterogeneous nature of their structures and their complicated catabolism. To fully describe the pharmacokinetics (PK) of an ADC, several analytes are commonly quantified, including total antibody, conjugate, and payload. Among them, conjugate is the most challenging to measure, because it requires detection of both small and large molecules as one entity. Existing...