Biologics Process Development, Bristol-Myers Squibb, Devens, MA, USA.
Biologics Process Development, Bristol-Myers Squibb, Devens, MA, USA.
J Chromatogr A. 2020 Dec 6;1633:461635. doi: 10.1016/j.chroma.2020.461635. Epub 2020 Oct 22.
Viral clearance is an important performance metric for the downstream process of monoclonal antibodies (mAbs) due to its impact on patient safety. Anion exchange chromatography (AEX) has been well-accepted in the industry as one of the workhorse techniques for removing viruses, and is considered to be able to achieve high log clearance values under most operating conditions. However, it is not uncommon for viral clearance results on AEX to fall below the desired level despite operating under conditions that should achieve high clearance levels according to conventional wisdom of how this mode of chromatography operates. In this study, a design of experiment (DoE) approach was used to develop a more fundamental understanding of viral clearance during AEX chromatography using Minute Virus of Mice (MVM) on POROS HQ resin. Load pH, conductivity and virus concentration were evaluated as design factors for three mAbs with varying physical and chemical properties. The hydrophobicity and surface charge distributions of the molecules were found to be the most significant factors in influencing viral clearance performance, and the viral clearance trends did not seem to fit with conventional wisdom. To explain this seemingly unconventional behavior, we propose a new mechanism that suggests that interactions between the mAb and the virus have a major contribution on retention of the virus on the resin. This furthered understanding may help improve the predictability, performance and robustness of viral clearance during AEX chromatography.
病毒清除率是单克隆抗体（mAb）下游工艺的一个重要性能指标，因为它会影响患者安全。阴离子交换色谱（AEX）已被业界广泛接受，是去除病毒的主要技术之一，并且在大多数操作条件下被认为能够实现高对数清除值。然而，尽管操作条件符合该色谱模式的常规操作知识，应该达到高清除水平，但 AEX 上的病毒清除结果低于预期水平的情况并不少见。在这项研究中，使用设计实验（DoE）方法，使用 POROS HQ 树脂上的小鼠细小病毒（MVM），对 AEX 色谱过程中的病毒清除进行了更深入的研究。负荷 pH 值、电导率和病毒浓度被评估为具有不同物理和化学性质的三种 mAb 的设计因素。结果发现，分子的疏水性和表面电荷分布是影响病毒清除性能的最重要因素，而病毒清除趋势似乎不符合常规认知。为了解释这种看似非传统的行为，我们提出了一种新的机制，表明 mAb 和病毒之间的相互作用对病毒在树脂上的保留有重大贡献。这一进一步的理解可能有助于提高 AEX 色谱过程中病毒清除的可预测性、性能和稳健性。
