NMR-based Structural Integrity Analysis of Monoclonal Antibodies

This technical report presents a comparative study utilizing nuclear magnetic resonance (NMR) spectroscopy to analyze the structural integrity of therapeutic monoclonal antibodies, specifically Humira (adalimumab) and its biosimilars. The study evaluates the higher-order structure (HOS) of these biologic products under both normal and photo-stressed conditions. The findings indicate strong structural similarities among the products under normal conditions, while photo-stressed samples displayed notable structural differences, including increased methionine oxidation and localized conformational changes, particularly in the reference product. The analysis also highlights the influence of container closure systems and formulations on photostability. Various methodologies, including 1D and 2D NMR techniques, were employed to assess HOS, emphasizing the utility of NMR as a sensitive tool for comparative structural analysis. The report underscores the importance of accurate HOS assessment in ensuring the equivalence of biosimilars to their reference products, maintaining similar pharmacokinetic profiles and therapeutic effects.