Virus clearance by activated carbon for therapeutic monoclonal antibody purification

In our previous study, activated carbon (AC) was employed in the purification process of therapeutic monoclonal antibody (mAb) as a replacement for Protein A affinity chromatography. In addition, we established an innovative column-free flow-through purification process using AC filter. In these investigations, the effective clearance of impurities (high-molecular-weight species, low-molecular-weight species, host cell proteins, and DNA) was observed compared to the conventional Protein A platform purification process. In this study, virus removal capability of our established AC process (AC filter) was investigated using two model viruses, Murine Leukemia Virus (MuLV) and Minute Virus of Mice (MVM) with the combination of two filtration methods (single-pass filtration and re-circulation filtration) using three kinds of mAbs. We found effective clearance of both MuLV and MVM (>3 log reduction factor, LRF) in all mAbs. Not only filtration method but also re-circulation duration didn't affect LRF, and >3 LRF of virus removal could be achieved by only single-pass filtration. From these results, it is expected that AC will be a promising candidate for the virus removal unit operation for mAb purification processes.