Analytical

Simplification of Fed-Batch Processes with a Single-Feed Strategy

Chinese hamster ovary (CHO) cells commonly are used to produce recombinant proteins such as monoclonal antibodies (MAbs) for research, diagnostic, and therapeutic purposes. Culture processes typically rely on a fed-batch approach in which a basal medium enables initial cell growth. Concentrated feeds are used to prevent nutrient depletion, thereby extending culture duration and improving cell growth, viability, and protein titer. A neutral pH feed is desirable because culture pH should remain stable after feedings. The extremely low solubility of l-tyrosine…

Reducing Clinical-Phase Manufacturing Costs: Collaborating for Savings without Compromising Quality or Performance

In downstream purification of monoclonal antibodies (MAbs), the single greatest contributor to manufacturing costs is the expensive capture step typically based on protein A affinity chromatography. Almost since its introduction to bioprocessing, efforts have been made to reduce the cost of this step. Several alternative ligands have been promulgated as potential replacements for protein A, but they have proven difficult to adopt and scale up. Supplier companies have pushed for increases in capacity and economics, but those are always accompanied…

Design and Performance of Single-Use, Stirred-Tank Bioreactors

Single-use components and systems have been incorporated into many bioprocesses as an alternative to cleanable, reusable systems. A wide range of publications have detailed the reasons for this trend toward a single-use approach. Justification in many cases comes from process-specific benefits such as increased manufacturing flexibility — especially for contract manufacturing organizations (CMOs) — enhanced sterility assurance, elimination of cleaning, reduced capital investment, faster processing times with increased productivity, faster start-up, and other benefits (1). One critical factor in the…

Special Report on Process- and Product-Related Impurities (A CMC Strategy Forum Special Focus Series): Extractables, Leachables, Particles, and Aggregates

The CMC Strategy Forums focus on relevant chemistry, manufacturing, and controls (CMC) issues throughout the life cycle of a therapeutic and thereby foster collaborative technical and regulatory interaction. Forum chairs share information with regulatory agencies to help them merge good scientific and regulatory practices. Outcomes of forum meetings are published in BioProcess International and on the CASSS website (www.casss.org). This process is meant to help ensure that biopharmaceutical products manufactured with advancing technologies in a regulated environment will continue to…

Continuous Cell Culture Operation at 2,000-L Scale

In the biopharmaceutical industry, continuous manufacturing is often cited as a method for increasing the productivity of bioprocesses (1). Compared with batch processing, it has the potential to enable production of more product within a smaller facility footprint — while improving product quality, particularly for sensitive and unstable molecules. Investigation into continuous methods is taking place for both upstream and downstream operations. For the full benefit of continuous processing to be realized, an argument has been made that cell culture,…

Biosimilar Therapeutic Monoclonal Antibodies: Gaps in Science Limit Development of an Industry Standard for Their Regulatory Approval, Part 2

Last month, Part 1 of this discussion briefly described the regulatory landscape for developing biosimilar therapeutic monoclonal antibodies (TMAbs). We identified certain specific structural components of TMAb drug substances that warrant particular attention because alterations to them are likely to affect therapeutic safety and effectiveness. Now we conclude by considering whether studies of reference materials can further the development of analytical industry standards to ensure comparability of putative biosimilar TMAbs with innovator TMAbs. We suggest that the time is right…

Mass Spectrometric Conjugate Characterization: Process Qualification of Recombinant Protein–Hapten Conjugation

Conjugated protein biotherapeutics such as PEGylated proteins (with polyethylene glycol), antibody–drug conjugates (ADCs), and protein–haptens often present unique analytical challenges related to characterizing the conjugation aspect of their manufacturing processes. Analytical characterization of this class of proteins requires knowledge of the sites of conjugation, the degree of conjugation, and the drug-to-protein ratio. Here we present case studies in development of reliable methods based on mass spectrometry (MS) to characterize a protein–hapten drug substance during late-phase process validation. This protein is…

Providing Lipids Boosts Protein Productivity: Testing a Feed Supplement with Multiple Cell Clones and Media Formulations

As the biologics (and now biosimilar) markets continue to grow, pressure increases on biomanufacturers to reduce cost of goods sold (CoGS). One way they can reduce cost is by increasing protein productivity in terms of protein titer per volume of culture. Media optimization is a key strategy for increasing protein productivity. In the past few decades, average titers across the industry have increased greatly — from <0.5 g/L in the 1980s to >3 g/L today, and it is not uncommon…

Advanced Protein Engineering Enhances Biopharmaceutical Manufacturing and Analytics

Production of proteins for pharmaceutical use is a complex, multistep process that requires technologies for purifying such molecules from highly complex biological mixtures. It also calls for reliable, cost-effective, high-throughput analytical techniques to determine protein quality and functionality to ensure the safety and efficacy of end-products. Mistakes in product development and manufacturing not only are immensely costly, but they can also put patients at risk. Many well-established processes and analytical tools are available for use in manufacturing antibody drugs (e.g.,…

Special Report: A Strategy for Cost-Effective Capture Using Agarose-Based Protein A Resins

It is well recognized that the cost of Protein A resins is substantial. If a developmental monoclonal antibody (MAb) makes it to marketing approval and manufacturing, the high cost of purification using a Protein A resin is amortized over a large number of purification cycles, and the contribution to cost of goods is reduced to acceptable levels. However, a high percentage of clinical projects will fail, and the Protein A resin will be used only for a small number of…