July 23, 2024
An antibody-drug conjugate (ADC) represents a biopharmaceutical molecule comprising the monoclonal antibody (mAb) delivery component, which is conjugated traditionally to a highly potent cytotoxin via a chemical linker though other conjugated moieties are being developed. Regardless of the conjugate, the analytical approach is similar. All three components, mAb, cytotoxin and chemical linker, are crucial to the efficacy of the ADC, as well as the drug antibody ratio (DAR). Additionally, they must be addressed when it comes to the selection of analytics for release testing, stability testing, as well as characterization and comparability analysis. Adding to the complexity of analyzing ADC product is the analytical requirement for mAb intermediate, cytotoxic drug intermediate, drug substance and drug product, with the production of these materials often occurring at different manufacturing sites.