Recently developed multi-specific antibody formats enable new therapeutic concepts. Conveniently, formats with an Fc domain allow purification in well-established mAb platform processes. However, due to the structural complexity of the formats, the assembled molecules may be sensitive to extreme pH commonly used for viral inactivation. An alternative to low pH incubation for virus inactivation is the use of a mixture of tri-n-butyl phosphate (TnBP, solvent) and Polysorbate 80 (PS80, detergent). While TnBP is toxic, this combination has a long history of use in the manufacturing of human plasma-derived products that are sensitive to low or high pH incubation. Data are provided demonstrating that the solvent/detergent (S/D) treatment using TnBP and PS80 can be successfully used for pH-sensitive, multi-specific antibody formats in the clarified cell culture fluid (CCCF). A different placement of the S/D within the purification process, namely during the capture by Protein A (PA), has been evaluated. This alternative placement allows effective viral inactivation by S/D while preserving the viral reduction and viral inactivation achieved through the PA step itself, enabling the cumulation of these effects. Furthermore, the process alternative simplifies the liquid handling by reducing the added volumes of the required S/D liquids, thus reducing the amount of toxic TnBP to a minimum. Data are shown demonstrating a complete removal of TnBP and PS80 in the process.

中文翻译：

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pH 敏感抗体形式（例如多特异性抗体）的病毒灭活

最近开发的多特异性抗体形式实现了新的治疗概念。方便的是，具有 Fc 结构域的格式允许在完善的 mAb 平台工艺中进行纯化。然而，由于形式的结构复杂性，组装的分子可能对病毒灭活常用的极端pH敏感。低 pH 孵育病毒灭活的另一种方法是使用磷酸三正丁酯（TnBP，溶剂）和聚山梨酯 80（PS80，洗涤剂）的混合物。虽然 TnBP 有毒，但这种组合在制造对低或高 pH 孵化敏感的人血浆衍生产品中有着悠久的使用历史。提供的数据表明，使用 TnBP 和 PS80 进行溶剂/去垢剂 (S/D) 处理可成功用于澄清细胞培养液 (CCCF) 中的 pH 敏感型多特异性抗体形式。已经评估了纯化过程中 S/D 的不同位置，即在蛋白 A (PA) 捕获期间。这种替代放置允许通过 S/D 有效灭活病毒，同时保留通过 PA 步骤本身实现的病毒减少和病毒灭活，从而实现这些效果的累积。此外，该工艺替代方案通过减少所需 S/D 液体的添加量来简化液体处理，从而将有毒 TnBP 的量降至最低。数据显示在此过程中 TnBP 和 PS80 被完全去除。