Monoclonal Antibody (mAb)

While core assays—such as identity, purity, potency, and safety—remain central throughout development and commercialization, the scope and stringency of testing evolve across bulk harvest (BH), drug substance (DS), drug product (DP), and stability stages.

At bulk harvest, testing emphasizes in-process controls and safety assessments, including bioburden, mycoplasma, and adventitious agent testing, as well as monitoring of host cell protein (HCP) and host cell DNA clearance.

For drug substance release, testing focuses on confirmation of molecular identity (e.g., peptide mapping, mass spectrometry), purity and heterogeneity (e.g., SEC for aggregates, CE-SDS, charge variants), glycosylation profiling, residual impurities (HCP, DNA, Protein A), potency through mechanism-of-action–relevant bioassays, and compendial safety testing such as sterility and endotoxin.

Drug product release builds upon DS testing with additional assessments of formulation-specific attributes, container closure integrity, particulate matter, and stability-indicating assays. Stability programs then verify that the mAb maintains its critical quality attributes—including structural integrity, biological activity, and safety profile—throughout its labeled shelf life under defined storage conditions.

Together, these stages form an integrated control strategy that ensures consistent mAb quality from cell culture through final patient administration.