A steady increase of product titers and the corresponding change in impurity composition represent a challenge for development and optimization of antibody production processes. Additionally, increasing demands on product quality result in higher complexity of processes and analytics, thereby increasing the costs for product work-up. Concentration and composition of impurities are critical for efficient process development. These impurities can show significant variations, which primarily depend on culture conditions. They have a major impact on the work-up strategy and costs. The resulting "bottleneck" in downstream processing requires new optimization, technology and development approaches. These include the optimization and adaptation of existing unit operations respective to the new separation task, the assessment of alternative separation technologies and the search for new methods in process development. This review presents an overview of existing methods for process optimization and integration and indicates new approaches for future developments.

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Trends in Upstream and Downstream Process Development for Antibody Manufacturing

Continuous downstream processing of biopharmaceuticals

White paper on continuous bioprocessing. May 20-21, 2014 Continuous Manufacturing Symposium.

There is growing interest in the possibility of developing truly continuous processes for the large-scale production of high value biological products. Continuous processing has the potential to provide significant reductions in cost and facility size while improving product quality and facilitating the design of flexible multi-product manufacturing facilities. This paper reviews the current state-of-the-art in separations technology suitable for continuous downstream bioprocessing, focusing on unit operations that would be most appropriate for the production of secreted proteins like monoclonal antibodies. This includes cell separation/recycle from the perfusion bioreactor, initial product recovery (capture), product purification (polishing), and formulation. Of particular importance are the available options, and alternatives, for continuous chromatographic separations. Although there are still significant challenges in developing integrated continuous bioprocesses, recent technological advances have provided process developers with a number of attractive options for development of truly continuous bioprocessing operations.

Continuous downstream processing for high value biological products: A Review

Integrated and continuous processing of recombinant proteins offers several advantages over batch or semi-batch processing used traditionally in the biotechnology industry. This paper presents a theoretical and practical approach for designing a periodic counter-current chromatography (PCC) operation as a continuous capture purification step that is integrated with a perfusion cell culture process. The constraints for continuous and optimal PCC operation govern the selection of residence time and number of columns. The flexibility available in PCC design for selection of these parameters is dictated by the binding characteristics of the target protein on the capture resin. Using an empirical model for the protein breakthrough curve, analytical solutions to determine these conditions were derived and verified with experimental results for three different proteins: two relatively unstable proteins (recombinant enzymes) and a relatively stable protein (monoclonal antibody). The advantages of a continuous downstream capture step are highlighted for the three case studies in comparison with the existing batch chromatography processes. The use of PCC leads to improvements in process economics due to higher resin capacity utilization and correspondingly lower buffer consumption. Furthermore, integrated and continuous bioprocessing results in a smaller facility footprint by elimination of harvest hold vessels and clarification, as well as by reducing the capture column size by one to two orders of magnitude.

Periodic counter-current chromatography – design and operational considerations for integrated and continuous purification of proteins

In the current environment of diverse product pipelines, rapidly fluctuating market demands and growing competition from biosimilars, biotechnology companies are increasingly driven to develop innovative solutions for highly flexible and cost-effective manufacturing. To address these challenging demands, integrated continuous processing, comprised of high-density perfusion cell culture and a directly coupled continuous capture step, can be used as a universal biomanufacturing platform. This study reports the first successful demonstration of the integration of a perfusion bioreactor and a four-column periodic counter-current chromatography (PCC) system for the continuous capture of candidate protein therapeutics. Two examples are presented: (1) a monoclonal antibody (model of a stable protein) and (2) a recombinant human enzyme (model of a highly complex, less stable protein). In both cases, high-density perfusion CHO cell cultures were operated at a quasi-steady state of 50-60 × 10(6) cells/mL for more than 60 days, achieving volumetric productivities much higher than current perfusion or fed-batch processes. The directly integrated and automated PCC system ran uninterrupted for 30 days without indications of time-based performance decline. The product quality observed for the continuous capture process was comparable to that for a batch-column operation. Furthermore, the integration of perfusion cell culture and PCC led to a dramatic decrease in the equipment footprint and elimination of several non-value-added unit operations, such as clarification and intermediate hold steps. These findings demonstrate the potential of integrated continuous bioprocessing as a universal platform for the manufacture of various kinds of therapeutic proteins.

Integrated continuous production of recombinant therapeutic proteins

In this study, we investigated the effects of alternating tangential flow (ATF) cell separation on high-density perfusion cultures. We have developed methods to estimate theoretical residence times of cells in the ATF system and discovered that long residence times (above 75 s) correlate with decreased growth, metabolism, and productivity. We have calculated energy dissipation rates in the ATF transfer line and filter and empirically studied the impacts of increased exchange rates on cell culture, determining that increased hydrodynamic stress can lead to decreased cell size, lactate production, and specific productivity. Finally, we have conducted experiments to understand the relationship between filtration fluxes and ATF membrane fouling, finding that at fluxes above 60 L·m-2 ·day -1 , protein sieving coefficients see significant rates of decrease (greater than 1% per day). While most of these studies have been conducted with one cell line at one target viable cell density (40 million cells/ml), the general, directional knowledge arising from this study should be applicable to other conditions and programs, ultimately leading to more robust and well-designed perfusion processes.

The effects of alternating tangential flow (ATF) residence time, hydrodynamic stress, and filtration flux on high-density perfusion cell culture.

Provided herein are methods of culturing a mammalian cell in a liquid medium including poloxamer-188 at a concentration of 1.8 g/L or at a greater concentration than 1.8 g/L more or a liquid medium that includes a poloxamer-188 concentration that is selected based on one or more factors selected from the group of: pore size, pore type, gas flow rate, viable cell density in the medium, and markers related to cell stress.

Methods of culturing a mammalian cell

FIELD: biotechnology.SUBSTANCE: invention relates to biotechnology, specifically to methods for cultivation of Chinese hamster ovary cells (CHO). Method comprises perfusion cultivation of CHO cell containing nucleic acid coding recombinant protein, under conditions sufficient for production of recombinant protein in a liquid medium containing poloxamer-188 in concentration 1.8 g/l or more 1.8 g/l.EFFECT: invention widens the range of equipment.22 cl, 5 ex, 1 tbl, 15 dwg

Methods of culturing mammalian cell

Provided herein are methods of predicting the effect of a concentration of a sensitizer on cell viability in a production bioreactor, methods of improving cell viability in a production bioreactor, methods of predicting cell viability in a production bioreactor, and methods for culturing a cell in a production bioreactor.

Johnson Timothy

Papers

Integrated continuous production of recombinant therapeutic proteins

The effects of alternating tangential flow (ATF) residence time, hydrodynamic stress, and filtration flux on high-density perfusion cell culture.

Methods of culturing a mammalian cell

Methods of culturing mammalian cell

Methods for Improvidng Cell Viability In A Production Bioreactor