Analytical characterization plays an important role in ensuring product integrity and manufacturing consistency, which are essential for demonstrating safety and efficacy to the FDA and other regulatory authorities. However, the heterogeneity of ADCs makes the analytical characterization particularly challenging. Selection of appropriate analytical techniques depends on the properties of the linker, the drug and the choice of attachment site. The Pace Life Sciences Boston, MA development site uses common analytical methods to assess the physicochemical and biophysical properties of ADCs, including mass spectrometry-based techniques, chromatographic techniques, electrophoresis, particulates analysis and hybrid techniques, as summarized in the following table.

Attribute
Technique
Identity
cSDS, cIEF
Purity (deamidation and half antibody levels)
RPLC, cSDS
pI/Charge Variants
cIEF, CZE, IEX
Size/Aggregation
DLS, MALS, SEC
Concentration
UV-Vis
Average DAR
UV-Vis
Potency
ELISA
Structural stability
DSC
Post-translational modifications
Peptide mapping
Identification of conjugation sites
Peptide mapping