Integrated double flow-through purification of monoclonal antibodies using membrane adsorbers and single-pass tangential flow filtration

A flow-through process for monoclonal antibody (mAb) purification has been created by integrating two different membrane adsorbers (MAs) with single-pass tangential flow filtration (SPTFF) for continuous buffer exchange. First, a design of experiments (DoE) was carried out to investigate the influence of pH and conductivity on the removal of desoxyribonucleic acid (DNA) and host cell proteins (HCP), and to select buffer conditions for mAb flow-through mode operation for four different MAs. As next, breakthrough curve experiments were performed with the selected buffer conditions for each MA to analyze the binding behavior of mAb, DNA, and HCP. Then, the influence of the MA sequence in the double flow-through process on the mAb yield and DNA and HCP removal was studied in batch mode. The best sequence of MAs was used for the final integrated double flow-through polishing process, where the MAs were directly connected via SPTFF. The flow-through of the first (anion exchange) MA was continuously diafiltrated via SPTFF to buffer conditions for the second (cation exchange) MA. In this way, DNA (< 2 ppm) and HCP (< 29 ppm) were removed with simultaneously high mAb yield. Moreover, 36 times higher throughput was obtained than with a standard process that combines a packed-bed column with CEX resin in a bind and elute mode with an AEX MA in flow-through mode.