Anion exchange membrane adsorbers for flow‐through polishing steps: Part I. clearance of minute virus of mice

Abstract

Membrane adsorbers may be a viable alternative to the packed-bed chromatography for clearance of virus, host cell proteins, DNA, and other trace impurities. However, incorporation of membrane adsorbers into manufacturing processes has been slow due to the significant cost associated with obtaining regulatory approval for changes to a manufacturing process. This study has investigated clearance of minute virus of mice (MVM), an 18-22 nm parvovirus recognized by the FDA as a model viral impurity. Virus clearance was obtained using three commercially available anion exchange membrane adsorbers: Sartobind Q®, Mustang Q®, and ChromaSorb®. Unlike earlier studies that have focused on a single or few operating conditions, the aim here was to determine the level of virus clearance under a range of operating conditions that could be encountered in industry. The effects of varying pH, NaCl concentration, flow rate, and other competing anionic species present in the feed were determined. The removal capacity of the Sartobind Q and Mustang Q products, which contain quaternary ammonium based ligands, is sensitive to feed conductivity and pH. At conductivities above about 20 mS/cm, a significant decrease in capacity is observed. The capacity of the ChromaSorb product, which contains primary amine based ligands, is much less affected by ionic strength. However the capacity for binding MVM is significantly reduced in the presence of phosphate ions. These differences may be explained in terms of secondary hydrogen bonding interactions that could occur with primary amine based ligands.

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

“…First, most AEX resins employ quaternary ammonium ligands, which typically require conductivities below 10 mS/cm for proper binding . To overcome this, a dilution or buffer exchange step is often employed to reduce conductivity, creating tank size and productivity bottlenecks along with increased water and buffer consumption . Second, since AEX polishing is used to bind dilute impurities, it is possible that the column may be operated under unfavorable isotherm conditions, resulting in loadings below the resin's maximum binding capacity.…”

The effects of buffer condition on the fouling behavior of MVM virus filtration of an Fc‐fusion protein

“…The primers and qPCR conditions have been reported previously(Weaver et al, 2013). The total volume after these two steps was 55 µl, from which 1 µl of the sample was taken and mixed with 9 µl of a mixture containing iTaq™ universal SYBR green supermix (Bio-Rad, Hercules, CA), water, and primers.…”

Adapting viral safety assurance strategies to continuous processing of biological products

“…Of the possible membrane adsorber moieties available, AEX membrane adsorbers are already known to efficiently clear mammalian viruses (Miesegaes et al, ; Phillips et al, ) across wide pH ranges (Strauss et al, ), and viral pIs (Miesegaes et al, , ; Valera et al, ). However, technological gaps have been identified as some buffer conditions required for a lower pI monoclonal antibody product can reduce clearance efficiency when product is present (Weaver et al, ,). For CP, AEX membrane adsorbers are the most attractive/cost‐effective resin for continuous flow‐through operation, since they can easily be exchanged when they are clogged.…”