Regeneron Pharmaceuticals, Inc.
SITE-SPECIFIC QUANTITATION OF DRUG CONJUGATIONS

Abstract:

A method for site-specific quantitation or characterization of drug conjugations of antibody-drug conjugates using protease-assisted drug deconjugation, linker labelling and mass spectrometry, wherein the conjugation includes an attachment linked to a specific conjugation site of a partially conjugated peptide or protein in a sample. The method comprises cleaving a portion of the attachment to generate the peptide or protein containing a cleaved linker, adding a modified linker to an unconjugated conjugation site of the partially conjugated peptide or protein, and subsequently subjecting the sample to mass analysis to identify the peptide or protein containing the cleaved linker and/or the modified linker.