Biologics Upstream Process Development, Merck & Co., Inc., Kenilworth, New Jersey, USA.
Biologics Downstream Process Development, Merck & Co., Inc., Kenilworth, New Jersey, USA.
Biotechnol Prog. 2022 Jul;38(4):e3262. doi: 10.1002/btpr.3262. Epub 2022 May 2.
Intensified perfusion processes are an integral part of continuous manufacturing for biopharmaceuticals which enable agile operations and significant reduction in cost of goods. However, they require large volumes of media to support robust cell growth and maintain high productivity, posing substantial challenges to operations, logistics, and process sustainability. This study explores a novel strategy for reprocessing and reusing permeate from perfusion cultures for mAb production. The concept was initially evaluated by recycling permeate, Protein A flow-through (ProA FT) and CEX processed ProA FT in deep-well plate mock perfusion and ambr® 250 perfusion formats. Further processing of ProA FT through a cation exchange depth filter before recycling reduced process impurities such as host cell proteins (HCPs) and DNA. However, a direct replacement of fresh media with spent media reduces nutrient depth which results in a concomitant reduction in productivity. In ambr® 250 bioreactors, recycling of ProA FT at 25%-50% replacement rates (defined as the fraction of recycled material in media) resulted in a 13%-30% reduction in cumulative productivity while maintaining product quality. To mitigate this, we used media concentrates which allowed independent modulation of media depth by replacing a portion of diluent WFI with recycled material. Results from deep-well mock perfusion studies demonstrated that comparable or higher productivities relative to control can be achieved with this approach. Taken together, our study demonstrates the feasibility of recycling permeate in perfusion cultures. Process mass intensity (PMI) calculations reveal that this approach can meaningfully improve material efficiency by reducing water consumption, thereby enhancing overall bioprocess sustainability.
强化灌注过程是生物制药连续制造的一个组成部分，它可以实现灵活的操作，并显著降低产品成本。然而，它们需要大量的介质来支持健壮的细胞生长并保持高生产力，这对操作、物流和过程可持续性带来了巨大的挑战。本研究探讨了一种从灌注培养物中再处理和再利用渗透物用于 mAb 生产的新策略。该概念最初通过在深孔板模拟灌注和 ambr®250 灌注格式中循环利用渗透物、Protein A 流穿（ProA FT）和 CEX 处理的 ProA FT 进行了评估。在循环利用之前，通过阳离子交换深度过滤器进一步处理 ProA FT，可以减少过程杂质，如宿主细胞蛋白（HCPs）和 DNA。然而，直接用用过的培养基代替新鲜培养基会降低营养物深度，从而导致生产力相应降低。在 ambr®250 生物反应器中，以 25%-50%的替换率（定义为回收材料在培养基中的比例）循环利用 ProA FT，可使累积生产力降低 13%-30%，同时保持产品质量。为了缓解这一问题，我们使用了培养基浓缩物，通过用回收材料替代一部分稀释剂 WFI，可以独立调节培养基深度。深孔模拟灌注研究的结果表明，与对照相比，采用这种方法可以实现相当或更高的生产力。总之，我们的研究表明在灌注培养物中再利用渗透物是可行的。过程质量强度（PMI）计算表明，这种方法可以通过减少水的消耗，显著提高材料效率，从而提高整体生物工艺的可持续性。
