Perfusion Cell Culture

Product Quality Attribute Shifts in Perfusion Systems, Part 2: Elucidating Cellular Mechanisms

Part 1 of this two-part report describes an investigation into the potential cause(s) and ways to control a product quality attribute (PQA) of a protein expressed in perfusion cell culture (1). The presence of low–molecular-weight (LMW) species following size-exclusion high-performance liquid chromatography (SEC-HPLC) is a protein quality attribute that can indicate an increase in truncated forms of the expressed protein and/or other LMW moieties. The expressed protein in this study is a heavily glycosylated recombinant glycoprotein (rGP) comprising two subunits:…

Intensified Seed Train Strategy for Faster, Cost-Effective Scale-Up of Biologics Manufacturing

The high costs of and limits on global accessibility of biologics such as monoclonal antibodies (MAbs) are focusing the biopharmaceutical industry’s attention on strategies for rapid, economical development of such therapies. Process intensification is one approach to help shorten manufacturing timelines and reduce cost of goods (CoG) (1, 2). Today, process intensification in upstream cell culture enables biologics manufacturing in facilities with smaller footprints and lower scale-up volumes than was possible before. Intensified processing of Chinese hamster ovary (CHO) clones…

Product Quality Attribute Shifts in Perfusion Systems, Part 1: Identifying Shifts When They Occur

Perfusion cell culture processes are continuous, with fresh media continuously added and spent media (harvest) removed simultaneously through a cell-retention device (Figure 1). To maintain specific bioreactor cell density, cells are removed periodically as cell bleed or discard. Perfusion systems offer a number of advantages over batch and fed-batch culture modes such as lower capital costs and an ability to support higher cell densities with better viability over longer manufacturing campaigns requiring shorter turn-around times. However, perfusion systems require complex…

The Upstream Perspective: Taking Efficiency Beyond Cell-Line Development

With 20 years of experience in the biopharmaceutical industry — at Genentech, Applied Biosystems, Cell Genesys, Cellerant Therapeutics, and Bayer — Yuval Shimoni has written frequently for BioProcess International on a number of production topics. Those have ranged from process improvements and bioreactor scale-down validation, to raw materials management, to addressing variability and virus contamination events. For this featured report, we discussed hardware and instrumentation, quality by design (QbD) and related approaches, and other strategies that can take expediting upstream…

Advances and Challenges in Vaccine Development and Manufacture

Scientists have made significant breakthroughs in bioprocess and analytical technologies for supporting vaccine development. Such technologies have helped vaccine manufacturers achieve consistent product purity and quality rapidly and cost effectively. Although interest in vaccine development and manufacture continues to increase because of the rapid growth of the global vaccine market, this area of the bioprocess industry remains challenging and complex. Here we review the current constraints and complexities in the vaccine industry, specifically related to product development and manufacture. We…

Cell Culture Bioprocessing in Perfusion: Assessing Cell Retention Technologies

Upstream bioprocessing in perfusion mode holds great promise for industrial production of cells and biologics. In perfusion, fresh medium is added constantly to the bioreactor, and used medium is harvested while the cells are retained in the bioreactor. As a result, the composition of the cell culture medium stays quite constant during the process. This offers several advantages. In perfusion, higher cell densities can be reached than in batch and fed-batch processes, therefore enhancing volumetric productivity. Because medium composition can…

Accelerating Intensified Bioprocesses with High-Throughput Small-Scale Tools

While many biopharmaceutical companies are exploring paths toward continuous processing, many tools already exist for implementing process intensification. As the authors of this special report illustrate, hybrid continuous processes that benefit from single-use technologies along with continuing improvements in perfusion cell culture already now are enabling improvements in cost reduction and accelerating time to market. And novel high-throughput and automated small-scale systems are helping development scientists gather more information in less time than before, reduce their development footprints, and make…

Reducing Variability in Cell-Specific Productivity in Perfusion Culture: A Case Study

Variation in bioproduction is recognized in the industry and often attributed to one or more of four sources: raw materials (including consumables), operational inputs (measurements, methods, personnel, equipment), environmental factors, and biological variation inherent to living cells (1). Variability can occur even among replicate units regardless of production mode (e.g., fed-batch or perfusion), and it can manifest as variability in productivity, cell metabolism, and/or product quality (2–4). In commercial biomanufacturing, meeting all product quality attributes is a requirement for regulatory…

Continuous Processes: Disposables Enable the Integration of Upstream and Downstream Processing

Despite decades of advancement in characterization analytics, biotherapeutics still are largely defined by the manufacturing processes used to make them. This linking of process to clinical results (and thus to commercial success) has made the biopharmaceutical industry somewhat risk-averse when it comes to the adoption of new technologies. That desire to “derisk” biomanufacturing through better process understanding — as well as the need to adapt to uncertainties in patient population size through process flexibility — in turn drives the need…

Difficult-to-Express Proteins: Resolving Bioprocessing Challenges with a Scalable Perfusion Bioreactor

Recent advances in protein engineering have identified new classes of complex biotherapeutics that challenge existing manufacturing platforms. These products have unique cell culture requirements that make them difficult to manufacture cost effectively. Industry standard bioprocessing platforms include large-scale (1,000–5,000 L) batch and fed-batch stirred-tank bioreactors. Historically, the powerhouse molecule of the biologics industry has been human IgG, which necessitates those large-scale platforms. Difficult-to-express proteins and other new modalities (including precision medicine and orphan drugs) have increased pressure on manufacturers to…