Development Of High Throughput Screening Tools For Purification Of Bispecifics

Monoclonal antibodies have served as a cornerstone of therapeutic development for decades, yet their functionality can be limited. Recent advancements in protein engineering have enabled the creation of bispecific antibodies, harboring dual specificities. While various strategies have been established to ensure proper bispecific assembly, the possibility of mispairing and formation of monospecific homodimers persists. These unwanted byproducts necessitate extensive optimization of both upstream and downstream processing (USP/DSP).

This study presents the development of a high-throughput screening approach for purifying diverse bispecific formats. Three bispecific molecules targeting the same antigens were expressed in different configurations, each incorporating a distinct engineering strategy. Following small-scale expression in the AbZelect CHO platform, purification was attempted. While standard platform affinity capture and polishing steps proved effective for two constructs, the heterodimeric Fab/scFv-Fc format yielded unsatisfactory purity and recovery. We employed Cytiva PreDictor plates for high-throughput resin screening, allowing rapid development of an efficient purification method for this specific format. Examine how this work demonstrates the potential of high-throughput screening for identifying optimal purification strategies for various bispecific antibody formats, ultimately facilitating the development of these promising therapeutic candidates.