An alternative downstream process based on aqueous two-phase extraction for the purification of monoclonal antibodies

An alternative downstream process for the purification of a monoclonal antibody (mAb) based on aqueous two-phase extraction as clarification, capture and primary purification step was developed. For further purification unit operations which are commonly used for mAb platform processes were utilized. A diafiltration approach was used to combine virus inactivation and removal of phase forming components as well as low molecular weight impurities in one step followed by cation and anion exchange chromatography. Starting from cell containing cultivation broth, an overall mAb yield of 74 % was achieved within an application study. The process was optimized regarding mAb yield and the clearance of process related impurities like deoxyribonucleic acid as well as host cell proteins, which were removed to approximately 60 and 6000 ppm respectively. Critical product quality attributes, regarding glycosylation patterns, were also examined and remained unimpaired after the aqueous two-phase extraction. The alternative downstream process presented in this study offers great potential to improve mAb manufacturing.