Demonstration of continuous gradient elution functionality with automated liquid handling systems for high-throughput purification process development.

Various high-throughput systems and strategies are employed by the biopharmaceutical industry for early to late-stage process development for biologics manufacturing. The associated increases to experiment productivity and reduction in material consumption makes high throughput tools integral for bioprocess development. While these high-throughput systems have been successfully leveraged to generate high quality data representative of manufacturing scale processes, their data interpretation often requires complex data transformation and time-intensive system characterization. With respect to high throughput purification development, RoboColumns by Repligen operated on Tecan automated liquid handling systems offer superior performance scalability, but lack an optimized liquid delivery system that is representative of preparative chromatography. Particularly, stock Tecan liquid handling systems lack the capability to provide high-capacity continuous liquid flow and ideal linear gradient chromatography conditions. These limitations impact protein chromatography performance and hinder the application of high-throughput gradient elution experiments. In this work, we describe a Tecan Freedom EVO high-throughput purification tool that provides more continuous liquid delivery enabling continuous gradient elution capability for RoboColumn experiments as demonstrated by generation of highly linear conductivity gradients. Results demonstrate that the tool can provide RoboColumn performance and product quality data that is in agreement with larger, bench scale chromatography formats for two model purification methods. The described gradient purification method also provides more consistent performance between RoboColumns and larger column formats compared to step elution methods using the same optimized Tecan system. Lastly, new insights into the impact of discontinuous flow on RoboColumn elution performance are introduced, which may help further improve application of these data towards bioprocess development.

Optimization of a platform process operating space for a monoclonal antibody susceptible to reversible and irreversible aggregation using a solution stability screening approach.

Platform manufacturing processes are widely adopted to simplify and standardize the development and manufacturing of monoclonal antibodies (mAbs). However, there are mAbs that do not conform to a platform design due to instability or other protein properties leading to a negative impact on product quality or process performance (non-platform mAb). Non-platform mAbs typically require prolonged development times and significant deviations from the platform process to address these issues due to the need to sequentially optimize individual process steps. In this study, we describe an IgG2 mAb (mAb A) that is susceptible to aggregation and reversible self-association (RSA) under platform conditions. In lieu of a sequential optimization approach, we evaluated the solution stability of mAb A across the platform operating space (solution stability screen). This screening design was used to identify interacting parameters that affected the non-platform mAb stability. A subsequent response surface design was found to predict an acceptable operating space that minimized aggregate formation and RSA across the entire process. This information guided the selection of optimal parameters best suited to avoid destabilizing conditions for each process step. Substantial time savings was achieved by focusing development around these factors including protein concentration, buffer pH, salt concentration, and excipient type. In addition, this work enabled the optimization of a cation exchange chromatography step that removed aggregate without yield losses due to the presence of reversible aggregation. The final optimized process derived from this study resulted in an increase in yield of ˜30% over the original process while maintaining the same level of aggregate clearance to match product quality. Solution stability screening is readily adapted to high throughput technologies to minimize material requirements and accelerate analytical data availability. Implementation of high throughput approaches will further expedite process development and enable enhanced selection of candidate drugs by including process development objectives.

Optimization of a micro-scale, high throughput process development tool and the demonstration of comparable process performance and product quality with biopharmaceutical manufacturing processes.

In this paper, we discuss the optimization and implementation of a high throughput process development (HTPD) tool that utilizes commercially available micro-liter sized column technology for the purification of multiple clinically significant monoclonal antibodies. Chromatographic profiles generated using this optimized tool are shown to overlay with comparable profiles from the conventional bench-scale and clinical manufacturing scale. Further, all product quality attributes measured are comparable across scales for the mAb purifications. In addition to supporting chromatography process development efforts (e.g., optimization screening), comparable product quality results at all scales makes this tool is an appropriate scale model to enable purification and product quality comparisons of HTPD bioreactors conditions. The ability to perform up to 8 chromatography purifications in parallel with reduced material requirements per run creates opportunities for gathering more process knowledge in less time.