Saleh David, Wang Gang, Mueller Benedict, Rischawy Federico, Kluters Simon, Studts Joey, Hubbuch Jürgen
Late Stage DSP Development, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany.
Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology (KIT), Institute of Engineering in Life Sciences, Karlsruhe, Germany.
Biotechnol Prog. 2021 Jan;37(1):e3081. doi: 10.1002/btpr.3081. Epub 2020 Sep 25.
Cation exchange chromatography (CEX) is an essential part of most monoclonal antibody (mAb) purification platforms. Process characterization and root cause investigation of chromatographic unit operations are performed using scale down models (SDM). SDM chromatography columns typically have the identical bed height as the respective manufacturing-scale, but a significantly reduced inner diameter. While SDMs enable process development demanding less material and time, their comparability to manufacturing-scale can be affected by variability in feed composition, mobile phase and resin properties, or dispersion effects depending on the chromatography system at hand. Mechanistic models can help to close gaps between scales and reduce experimental efforts compared to experimental SDM applications. In this study, a multicomponent steric mass-action (SMA) adsorption model was applied to the scale-up of a CEX polishing step. Based on chromatograms and elution pool data ranging from laboratory- to manufacturing-scale, the proposed modeling workflow enabled early identification of differences between scales, for example, system dispersion effects or ionic capacity variability. A multistage model qualification approach was introduced to measure the model quality and to understand the model's limitations across scales. The experimental SDM and the in silico model were qualified against large-scale data using the identical state of the art equivalence testing procedure. The mechanistic chromatography model avoided limitations of the SDM by capturing effects of bed height, loading density, feed composition, and mobile phase properties. The results demonstrate the applicability of mechanistic chromatography models as a possible alternative to conventional SDM approaches.
阳离子交换色谱法（CEX）是大多数单克隆抗体（mAb）纯化平台的重要组成部分。使用缩小模型（SDM）对色谱单元操作进行工艺表征和根本原因调查。SDM色谱柱的床层高度通常与各自的生产规模相同，但内径显著减小。虽然SDM能够在所需材料和时间较少的情况下进行工艺开发，但其与生产规模的可比性可能会受到进料组成、流动相和树脂性质的变化或取决于现有色谱系统的扩散效应的影响。与实验性SDM应用相比，机理模型有助于缩小不同规模之间的差距并减少实验工作量。在本研究中，将多组分空间位阻质量作用（SMA）吸附模型应用于CEX精制步骤的放大。基于从实验室规模到生产规模的色谱图和洗脱池数据，所提出的建模工作流程能够早期识别不同规模之间的差异，例如系统扩散效应或离子容量变化。引入了一种多阶段模型验证方法来衡量模型质量并了解模型在不同规模下的局限性。使用相同的先进等效性测试程序，针对大规模数据对实验性SDM和计算机模拟模型进行了验证。通过捕捉床层高度、负载密度、进料组成和流动相性质的影响，机理色谱模型避免了SDM的局限性。结果证明了机理色谱模型作为传统SDM方法的一种可能替代方法的适用性。
