Design space and robustness analysis of batch and counter-current frontal chromatography processes for the removal of antibody aggregates

Displacement to separate host‐cell proteins and aggregates in cation‐exchange chromatography of monoclonal antibodies

“…Whether explicitly stated or not, methods employing self-displacement chromatography are gradually emerging (Brown, Bill, Tully, Radhamohan, & Dowd, 2010;Ichihara et al, 2018Ichihara et al, , 2019Khanal et al, 2019;H. F. Liu et al, 2011;Vogg et al, 2020a;Vogg, Pfeifer, Ulmer, & Morbidelli, 2020b) in between, as obtained here, enables intentional and efficient fractionation to obtain a more pure product. Such findings indicate that a collection of impurities, comprising aggregates and basic charge variants and HCPs, displace the product and thus precede the productenriched zone in the system, while acidic variants and HCPs can be captured or allowed to flow through further downstream.…”

“…Although some studies have evaluated displacement for mAb aggregate removal (Ichihara et al, 2018, 2019; Reck et al, 2017; Stone et al, 2019; Suda et al, 2009; Vogg et al, 2020a; Wollacott et al, 2015), investigation of how displacement affects the population of HCPs has not extended beyond a secondary analysis validating the effectiveness of proposed methods (Ichihara et al, 2018, 2019; H. Liu & Tang, 2008; Ulmer et al, 2019; Wollacott et al, 2015). Unlike mAb aggregates, which, although heterogeneous, all originate from the mAb product, HCPs are a heterogeneous set of proteins of various biophysical properties, function, and abundance.…”

“…For example, protein aggregates (Khanal, Kumar, Westerberg, Schlegel, & Lenhoff, 2019; Reck, Pabst, Hunter, & Carta, 2017) and various charge variants (Khanal et al, 2019; Kumar, Leweke, von Lieres, & Rathore, 2015) are retained differently on CEX resins. This difference in retention has been leveraged to separate aggregates through salt gradient elution (Suda et al, 2009; Zhou et al, 2007), hybrid pH‐salt gradient elution (Khanal et al, 2019; Zhou et al, 2007), and flow‐through operation (Ichihara, Ito, & Gillespie, 2019; Ichihara, Ito, Kurisu, Galipeau, & Gillespie, 2018; Khanal et al, 2019; Suda et al, 2009; Ulmer, Vogg, Müller‐Späth, & Morbidelli, 2019; Vogg, Müller‐Späth, & Morbidelli, 2020a). Separation of mAb aggregates using flow‐through ion‐exchange chromatography is enabled by the displacement of bound monomer by incoming aggregates (Carta & Jungbauer, 2010).…”

“…However, overloading can contribute to yield loss (Khanal et al, 2019) because mAb monomers and aggregate have similar affinities to CEX resins. Combining overloading with a multicolumn setup not only allows capture of the initial breakthrough onto the subsequent columns but also reduces the required resin mass (Vogg et al, 2020a). To this end, Vogg et al have demonstrated a two-column counter-current flow-through chromatography setup to be more robust than similar batch processes for the separation of mAb aggregates.…”

“…Although some studies have evaluated displacement for mAb aggregate removal (Ichihara et al, 2018(Ichihara et al, , 2019Reck et al, 2017;Stone et al, 2019;Suda et al, 2009;Vogg et al, 2020a;Wollacott et al, 2015), investigation of how displacement affects the population of HCPs has not extended beyond a secondary analysis validating the effectiveness of proposed methods (Ichihara et al, 2018(Ichihara et al, , 2019H. Liu & Tang, 2008;Ulmer et al, 2019;Wollacott et al, 2015).…”