Leveraging Post-Translational Modifications Biofunctional Assays For The Characterization Of Charged Variants

The manufacture of protein-based drugs is complex and relies on using biological host systems. This can result in small changes in protein structure during production and formation of protein variants that can have a large impact on functionality. This heterogeneity — variations in the protein size, charge or structure — can significantly impact the safety and activity of the final biotherapeutic or biosimilar therapy, potentially hindering their beneficial effect. It is vital that charged variant profiles of biologics are adequately characterized, as many post-translational modifications (PTMs) may alter the charge of the molecule, in turn impacting its stability, pharmacokinetics and pharmacodynamics. In this article, Catalent explores protein variants, focusing on charged variants, by outlining their impact on protein-based drugs, and explain how specific characterization techniques can be used to determine product safety and efficacy.