Using multimodal chromatography for post-conjugation antibody-drug conjugate purification: A methodology from high throughput screening to in-silico process development

In this paper, a methodology for the development of a multimodal chromatography process is presented that is aimed at removal of under-conjugated antibody-drug conjugate (ADC) species. Two ADCs are used as case studies: One ADC results from site-directed conjugation to inserted cysteine residues and has a drug-to-antibody ratio (DAR) of two, the other is the product of conjugation to interchain disulfide bonds with a DAR of eight. First, filter plate screening studies are designed for the unconjugated antibody and the ADCs. Different metrics for the analysis of these data sets are presented and discussed. From this analysis, the selected process conditions are then carried out using a benchtop chromatography system to confirm the separations observed in the filter plate studies while simultaneously generating data to estimate steric mass-action isotherm and mass transport parameters for process simulation. This column model is then employed to develop separation processes in-silico for the removal of the unconjugated parent antibody and under-conjugated product variants. The optimized process conditions identified using the model are then verified experimentally. The methodology presented in this work utilizes multimodal chromatography for ADC purification and provides the framework for a streamlined systematic approach to process development. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

This paper presents a methodology for the development of a multimodal chromatography process aimed at removing under-conjugated antibody-drug conjugate (ADC) species. Filter plate screening studies are conducted for unconjugated antibody and ADCs, followed by analysis and confirmation of process conditions using a benchtop chromatography system. A column model is then used for in-silico development of separation processes for the removal of unconjugated parent antibody and under-conjugated product variants, with optimized conditions verified experimentally.