Strategies for developing design spaces for viral clearance by anion exchange chromatography during monoclonal antibody production

Abstract

The quality-by-design (QbD) regulatory initiative promotes the development of process design spaces describing the multidimensional effects and interactions of process variables on critical quality attributes of therapeutic products. However, because of the complex nature of production processes, strategies must be devised to provide for design space development with reasonable allocation of resources while maintaining highly dependable results. Here, we discuss strategies for the determination of design spaces for viral clearance by anion exchange chromatography (AEX) during purification of monoclonal antibodies. We developed a risk assessment for AEX using a formalized method and applying previous knowledge of the effects of certain variables and the mechanism of action for virus removal by this process. We then use design-of-experiments (DOE) concepts to perform a highly fractionated factorial experiment and show that varying many process parameters simultaneously over wide ranges does not affect the ability of the AEX process to remove endogenous retrovirus-like particles from CHO-cell derived feedstocks. Finally, we performed a full factorial design and observed that a high degree of viral clearance was obtained for three different model viruses when the most significant process parameters were varied over ranges relevant to typical manufacturing processes. These experiments indicate the robust nature of viral clearance by the AEX process as well as the design space where removal of viral impurities and contaminants can be assured. In addition, the concepts and methodology presented here provides a general approach for the development of design spaces to assure that quality of biotherapeutic products is maintained.

Investigating the combination of single‐pass tangential flow filtration and anion exchange chromatography for intensified mAb polishing

“…Because most mAbs feature basic isoelectric points (pIs), AEX chromatography can be operated near neutral pH to bind acidic host cell protein (HCP), virus, DNA, and leached protein A impurities, while allowing the positively charged mAb to flow through unbound . Typical mAb loadings for AEX polishing resins are between 50 and 200 g mAb/L resin, which allow for acceptable impurity clearance with >95% yield …”

Use of a noninfectious surrogate to predict minute virus of mice removal during nanofiltration

“…Bacteriophages, endogenous CHO Type C retrovirus‐like particles (RVLPs), and biologic feedstreams have been used in attempts to economically predict the outcomes of viral clearance studies . However, due to the differences in physicochemical characteristics of bacteriophage models and the complexities involved in producing purified and highly concentrated RVLP spiking stocks, the scope of utility for these surrogates have remained narrow.…”

Effects of pH, conductivity, host cell protein, and DNA size distribution on DNA clearance in anion exchange chromatography media

“…The operational range for conductivity and pH was based on conditions for which effective viral clearance was measured (assumed to be over 4 log 10 for the Xenotropic Murine Leukemia Virus), based on in‐house information. Several published studies have demonstrated robust viral clearance on various AEX chromatography media under comparable pH and conductivity ranges studied in this article …”