Development of an acidic / neutral antibody flow-through polishing step using salt-tolerant anion exchange chromatography

2015 For ‘acidic’ (pI < 7.0) or ‘neutral’ antibodies (pI: 7.0–8.0), it is challenging to operate traditional anion exchange chromatography in a product flow-through mode to achieve adequate clearance of HCP, DNA, leached ProA, HMW and viruses while maintaining high process yield. In this study, the authors developed a scalable mAb polishing step using a new salt tolerant chromatographic resin. Utilizing a combination of high-throughput condition screening in 96-well plates and optimization in smallscale column models, a polishing step was developed that demonstrated high process yield and efficient clearance of impurities for multiple acidic or neutral antibodies. Pilot scale production demonstrated scalability of the step. This polishing step can be easily integrated into most current Protein A/AEX two-column antibody purification platforms.