Enhancing Bispecific And Trispecific Antibody Purification Using Mixed-Mode Chromatography

Bispecific antibodies (BsAbs) and trispecific antibodies (TsAbs) have emerged as promising therapeutic modalities due to their ability to simultaneously engage multiple targets. However, compared to conventional monoclonal antibodies, BsAbs and TsAbs present significantly greater purification challenges arising from their structural complexity and format diversity. These challenges often lead to heterogeneous product-related impurities and closely related variants that are difficult to resolve using traditional chromatographic approaches.

Mixed-mode chromatography offers a powerful solution by combining multiple interaction mechanisms, thereby enabling enhanced separation resolution and selectivity. In particular, CHT™ ceramic hydroxyapatite, a mixed-mode chromatographic medium that integrates cation exchange and metal affinity interactions, has demonstrated strong capability in separating complex biomolecular mixtures. CHT is especially effective in the simultaneous removal of aggregates, host cell DNA, and other process-related impurities within a single purification step.

This study highlights the potential of mixed-mode chromatography, with a focus on ceramic hydroxyapatite, as a robust and efficient platform for addressing the unique downstream processing challenges associated with BsAbs and TsAbs. Case studies are presented to illustrate strategies for leveraging CHT in BsAbs and TsAbs purification.

Speaker: Zhang Wei, PhD, Principal Scientist, Group Leader, Downstream Processing, A*STAR Bioprocessing Technology Institute, Singapore