Analytical

The Multi-Mode Mimetic Ligand Library: A New Tool for Rapid Development of Downstream Processes

Recent developments in downstream processing of biomolecules — including continuous processing, bind–elute affinity capture, and flow-through polishing steps — have increased the need for greater selectivity from chromatography adsorbents. This has led to the introduction of a new generation of adsorbents: so-called “mixed-mode” or multimodal ligands. They provide greater selectivity and tolerance to process buffer composition than either ionexchange chromatography (IEC) or hydrophobic-interaction chromatography (HIC) alone can provide. Learn more in this Special Report from Steve Burton, Chief Executive Officer…

Data Science, Modeling, and Advanced PAT Tools Enable Continuous Culture

Bioprocesses traditionally use (fed-)batch cell culture processes for production of recombinant proteins and therapeutics. In batch bioprocessing, material flow is discrete, with a hold step between two unit operations, and product is harvested only once for each unit operation. Batch processes have been studied extensively and optimized through numerous advancements in experimental design (1, 2), monitoring (3–5), measurement techniques (6–9), and control strategies (10–12). However, such processes require large facility footprints for equipment (13) as well as sterilization, load, and…

The Relationship Between R2 and Precision in Bioassay Validation

Analytical linearity along with assessments of precision and accuracy determine the range for bioassays (1). Practitioners can include coefficient of determination (R2) criteria from a linearity study in the bioassay validation protocol. Herein I illustrate the relationship of R2 to study design and analytical method variation. Overview of the Simple Linear Regression Model Dilutional linearity assesses the “ability (within a given range) of a bioassay to obtain measured relative potencies that are directly proportional to the true relative potency of the…

Ensuring the Integrity of Single-Use Containers: Providing Robustness, Science, and Helium-Based Technology with a Detection Limit of 2 μm

Identifying the greatest defect size, both for liquid leaks and microbial ingress, is a fundamental step toward protecting the integrity of single-use systems (SUS) under real process conditions. Integrity testing of such systems may become a prerequisite in the future because they are used in the most critical process steps, with detection limits correlating to liquid leaks and microbial ingress. Such testing guarantees the sterility of drug substances and drug products packaged in single-use systems and, therefore, enhance patient safety.…

Cell Expansion with Dissolvable Microcarriers

In recent years we have seen an exponential increase in the number of companies testing and validating new regenerative medicine products. Many of these products are reaching late-phase trials with the potential to receive final approval and marketing authorization from regulatory agencies such as the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). In the past several years, we have seen successful launches of regenerative medicine products, including Holoclar (Holostem Advanced Therapies), Kymriah (tisagenlecleucel, Novartis), Yescarta…

Enhanced Galactosylation of Monoclonal Antibodies: Using Medium Supplements and Precursors of UDP-Galactose, Part 2

In Part 1 of this report, we described our development of a high-throughput assay for analyzing monoclonal antibody (MAb) glycans and how we used it to evaluate the effects of medium supplements on galactosylation of MAbs produced by two different cell lines (1). This month, we examine galactosylation of a MAb produced by a third cell line. A discussion follows on the benefits of this high-throughput assay before we highlight the similarities and differences in galactosylation among the three MAbs…

eBook: Development of a Representative Scale-Down UF/DF Model: Overcoming Equipment Limitations and Associated Process Challenges

Scale-down models (SDM) are physical, small-scale models of commercial-scale unit operations or processes that are used throughout the biopharmaceutical industry for validation studies, commercial deviation investigations, and postapproval process improvements. To support these studies, regulatory guidelines state that SDMs should be representative of the commercial process. For some downstream unit operations such as column chromatography, developing a representative SDM is straightforward because a linear scale-down approach can be used. However, developing a representative SDM for other downstream unit operations such…

Implementation of the BPOG Extractables Testing Protocols: Comparing USP and BPOG Extractables Data for Autoclaved Polyethersulfone Filters

Benefits of single-use technologies over traditional stainless-steel solutions in biopharmaceutical manufacturing include reductions in set-up times, cleaning/cleaning validation costs, elimination of cross-contamination risks, and smaller operating footprints. But despite increasing adoption of such systems, concerns remain about extractable and leachable (E&L) compounds from plastic single-use systems (SUS) components with the potential to compromise the efficacy and safety of final drug products. Such concerns are magnified by the growing number of SUS suppliers and the complex supply chain for SUS and…

Enhanced Galactosylation of Monoclonal Antibodies: Using Medium Supplements and Precursors of UDP-Galactose, Part 1

The biopharmaceutical industry needs better understanding of how monoclonal antibody (MAb) glycosylation is influenced by components in cultivation media — and it needs methods to exert some control over the structure of MAb glycans. That structure can affect MAb function. Thus, a high-throughput (HTP) assay is needed for characterizing MAb glycosylation so that developers can observe the effects of cultivation conditions on MAb glycosylation rapidly, with a goal of producing MAbs that have a desired glycan structure. The method also…

Therapeutic IgG-Like Bispecific Antibodies: Modular Versatility and Manufacturing Challenges, Part 2

Monoclonal antibodies (MAbs) are bivalent and monospecific, with two antigen-binding arms that both recognize the same epitope. Bispecific and multispecific antibodies, collectively referred to herein as bispecific antibodies (bsAbs), can have two or more antigen-binding sites, which are capable of recognizing and binding two or more unique epitopes. Based on their structure, bsAbs can be divided into two broad subgroups: IgG-like bsAbs and non–IgG-like bsAbs. We have chosen to focus on the former in this review. Part one provides a…