Pool‐less processing to streamline downstream purification of monoclonal antibodies

Abstract

With cell culture titers and productivity increasing in the last few years, pressure has been placed on downstream purification to look at alternative strategies to meet the demand of biotech products with high dose requirements. Even when the upstream process is not continuous (perfusion based), adopting a more productive and/or continuous downstream process can be of significant advantage. Due to the recent trend in exploring continuous processing options for biomolecules, several enabling technologies have been assessed at Biogen. In this paper, we evaluate the capability of one of these technologies to streamline and improve our downstream mAb purification platform. Current conventional downstream polishing steps at Biogen are operated in flow‐through mode to achieve higher loadings while maintaining good selectivity. As titers increase, this would result in larger columns and larger intermediate product pool holding tanks. A semicontinuous downstream process linking the second and third chromatography steps in tandem can reduce/eliminate intermediate holding tanks, reduce overall processing time, and combine unit operations to reduce validation burdens. A pool‐less processing technology utilizing inline adjustment functionality was evaluated to address facility fit challenges for three high titer mAbs. Two different configurations of polishing steps were examined: (i) anion exchange and hydrophobic interaction and (ii) anion exchange and mixed mode chromatography. Initial laboratory scale proof of concept studies showed comparable performance between the batch purification process and the pool‐less process configuration.

Investigating the combination of single‐pass tangential flow filtration and anion exchange chromatography for intensified mAb polishing

“…In this case, SPTFF can be designed to over‐concentrate the product so that the target AEX feed concentration is achieved after conductivity dilution. Recent advancements in inline pool adjustment technology can enable pH and/or conductivity manipulation between SPTFF and AEX operations without requiring a dedicated mixing tank . Integrating SPTFF and inline pool adjustment before AEX polishing reduces dilution buffer volumes, thus minimizing buffer tank requirements for smaller process footprint.…”

Biomanufacturing evolution from conventional to intensified processes for productivity improvement: a case study

“…33,40 In addition, integrated polishing operation of typically two-column steps (e.g., cation exchange chromatography (CEX), anion exchange chromatography (AEX), hydrophobic interaction chromatography) has effectively shortened processing time with elimination of intermediate holding vessels and intermediate pool adjustment steps. 30 Although integrating continuous upstream and downstream operation can maximize the benefit of continuous biomanufacturing, reports of such applications have been limited, even in laboratory and pilot scales. 7,[41][42][43] Semi-continuous biomanufacturing employing MCC capture and integrated polishing has rarely been implemented in routine GMP manufacturing for mAb production.…”

“… 28 , 29 The polishing chromatography steps have evolved from bind-elute to flow-through mode for streamlined operation and significantly improved throughput. 30 Nonetheless, with a substantial increase in upstream titers, the batch downstream operation is still a major productivity bottleneck in bioprocessing, and accounts for a substantial portion of the overall biomanufacturing cost. 6 , 8 Due mainly to its limited loading capacity and high cost, Protein A resins present a throughput challenge to batch downstream operation, especially when upstream titers exceed approximately 10 g/L.…”

Integrated flow-through purification for therapeutic monoclonal antibodies processing

“…connected two flow-through chromatography steps and successfully demonstrated a pool-less concept without intermediate product hold tanks. 24 …”