Analytical

Special Report on Assays, Test Methods, and Comparability The CMC Strategy Forum Series, Part 4, The Roles of Bioactivity Assays in Lot Release and Stability Testing

A January 2007 CMC Strategy Forum on the roles of bioactivity assays in lot release and stability testing was held in Washington, DC (1). Its purpose was to promote an understanding of the design and utility of bioassays throughout product development and to delineate the conditions under which surrogate assays could be used to determine product potency. Topics of discussion included appropriate assay selection at each stage of product development, the potential use of binding assays for potency testing, and…

Quantitative Risk Assessment of Bioaccumulation Attributable to Extractables and Leachables in Cellular Immunotherapy Biomanufacturing

Precious patient samples, contamination concerns, and limited product purification options have compelled manufacturers of cellular immunotherapies (iTx) such as chimeric antigen receptor T cells (CAR-T) and T-cell receptor (TCR) technologies toward the disposables industry. Such companies are implementing single-use technologies (SUTs) almost exclusively (1). But despite the dominance of disposable bioprocess platforms and their extraordinary growth in the iTx marketplace, researchers have made limited efforts to understand the perennial and critical bioprocessing risks of leachables and extractables. Here we outline…

Experiences with a Benchtop-Scale Glass Bioreactor: Engineering Data and Cultivation Results

Animal cell lines (the dominant expression systems in biopharmaceutical production processes) are mostly cultivated in stirred bioreactors (1). Although such bioreactors are widely accepted and applicable over a wide range of scales, engineering data for these systems are still lacking. Nevertheless, studies have shown that the correct choice of key parameters (e.g., power input, tip speed, mixing time, and oxygen mass transfer) can influence the growth of animal cell cultures (2). Therefore, detailed characterization is essential. It enables reliable scaling…

Identification and Quantification of Heat-Shock Protein 70: A Major Host-Cell Protein Contaminant from HEK Host Cells

Recombinant therapeutic proteins are commonly produced by cell lines such as Chinese hamster ovary (CHO), human embryonic kidney (HEK) 293, murine myeloma (NS0), and Escherichia coli bacterial cells. Host-cell proteins (HCPs) are indigenous proteins produced by those expression hosts and considered to be process-related impurities generated from the cell culture process (1). HCPs are potentially harmful and immunogenic to patients, and they can compromise the stability of protein drugs (2–4). For those reasons, HCPs must be consistently removed or reduced…

Comparison of Concentration Measurement Technologies in Bioprocess Solutions

Biopharmaceutical manufacturing involves complex process steps. Exacting production conditions are typically required to maximize the yield, purity, and quality of biological products. In recent years, process analytical technology (PAT) has been increasingly used to monitor key process and performance parameters in real time. That has enabled better control of production conditions. An important parameter required to achieve consistent results in many bioprocessing steps is solute concentration in process fluids. The Critical Need for Concentration Measurement Many biopharmaceutical manufacturing process steps require measuring…

Compatibility Assessment of a Model Monoclonal Antibody Formulation in Glass and Blow–Fill–Seal Plastic Vials

Blow–fill–seal (BFS) technology has been recognized by the industry as an advanced aseptic solution (1–3). Catalent Pharma Solutions has been commercially supplying sterile BFS products to the pharmaceutical industry for decades, primarily in the respiratory and topical ophthalmic markets. Such product formulations range from simple solutions to emulsions with drug substances from classical small molecules to large complex proteins such as biologics. The company also has optimized BFS processes and its Advasept plastic container system for the manufacture of sterile…

Analysis and Characterization: The CMC Strategy Forum Series, Part 3 — Introduction

The CMC Strategy Forums provide a venue for biopharmaceutical product discussion. They 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 the 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…

Uniting Small-Molecule and Biologic Drug Perspectives: Analytical Characterization and Regulatory Considerations for Antibody–Drug Conjugates

Cosponsored by CASSS (an international separation science society) and the US Food and Drug Administration (FDA), the January 2010 CMC Strategy Forum explored antibody–drug conjugates (ADCs), which are monoclonal antibodies (MAbs) coupled to cytotoxic agents. The ADC platform of products is being used more and more for clinical evaluation in oncology. More than a dozen companies are developing several types, including products conjugated with calicheamicin, auristatins, and maytansinoids. Such products use the specificity of a MAb to deliver a cytotoxic…

Glycosylation of Therapeutic Proteins: Current Understanding of Structure–Function Relationships

A CMC Strategy Forum held in Washington, DC, on Sunday 28 January 2007 focused on two topics related to protein structure and function (1). First, analytical techniques used in the glycan analysis characterization included recent advances and correlations among the various tools. And second, current understanding of glycosylation’s functional relevance to therapeutic proteins was discussed in the context of its effects on biological activity, pharmacokinetics, and Fc effector functions (for monoclonal antibodies, MAbs). Progress has been made in the field…

Analysis and Structure Characterization of Monoclonal Antibodies

On 6 January 2003, 129 attendees participated in the second Well-Characterized Biotechnology Product (WCBP) Chemistry and Manufacturing Controls (CMC) strategy forum, titled “Analysis and Structure Characterization of Monoclonal Antibodies (MAbs),” held in San Francisco to discuss lot release and characterization test issues specific to MAbs (1). The objective of the meeting was twofold: to identify a “core” set of assays most useful for lot-release testing of MAbs and to define a mechanism for selecting appropriate potency tests. Two separate workshops…