Design and optimization of membrane chromatography for monoclonal antibody charge variant separation

Abstract

The manufacturing scale implementation of membrane chromatography to purify monoclonal antibodies has gradually increased with the shift in industry focus toward flexible manufacturing and disposable technologies. Membrane chromatography are used to remove process-related impurities such as host cell proteins (HCPs) and DNA, leachates, and endotoxins, with improved productivity and process flexibility.However, application of membrane chromatography to separate product-related variants such as charge variants has not gained major traction due to low-binding capacity. The work reported here demonstrates that a holistic process development strategy to optimize static binding (pH and salt concentration) and dynamic process (membrane loading, flowrate, and gradient length) parameters can alleviate the capacity limitations. The study employed high throughput screening tools and scale-down membranes for intermediate and polishing purification of the model monoclonal antibody. An optimized process consisting of anion exchange and cation exchange membrane chromatography reduced the acidic variants present in Protein A eluate from 89.5% to 19.2% with 71% recovery of the target protein. The membrane chromatography process also cleared HCP to below limit of detection with 6-to 30-fold higher membrane loading, compared to earlier reported values. The results confirm that membrane chromatography is effective in separating closely related product variants when supported by a well-defined process development strategy.

Advances in high‐throughput, high‐capacity nonwoven membranes for chromatography in downstream processing: A review

“…Since these membranes had very low binding capacity, it was thought to place them on top of each other so as to arrange them in layered stacks and form columns (Etzel, 2003; H.‐C Liu & Fried, 1994). Due to their low capacity, cast membranes have also been commonly used in a flow‐through or frontal mode for product polishing by removing product and process impurities after the product capture step (Nadar et al, 2022; Trnovec et al, 2020; Vogg et al, 2020). However, the use of membranes in a bind‐and‐elute mode for product capture and purification is not common since the relatively low surface area of cast membranes when compared with traditional chromatography resins limits their maximum binding capacity.…”

A novel method for continuous chromatographic separation of monoclonal antibody charge variants by combining displacement mode chromatography and step elution

“…Cation exchange chromatography is commonly used as a polishing step for removal of charge variants owing to the robustness and the efficiency to resolve the charge variants. 13,14 Charge variant separation by CEX is generally performed in a gradient based elution [15][16][17][18][19] or can also be performed in multi-step gradient. 20 While effective, implementation in a continuous downstream train offers challenges.…”