QA/QC

Viral Vector Particle Integrity and Purity Analyses in Early Process Development

Gene therapy is the transfer of genetic material to a patient’s cells to achieve a therapeutic effect. Therapeutic DNA typically is delivered using a viral vector system, and adenoviruses have been used for this purpose for over 20 years (1–3). Within the past 10 years or so, lentiviruses have shown promise in clinical trials (1–3), and adenoassociated viruses (AAVs) have been used in the first approved gene therapies in the Western world (4). The number of gene therapy applications based…

Development of a Host-Cell Protein Platform Assay for a Chinese Hamster Ovary Cell Line

The Chinese hamster ovary (CHO) cell line is the most prevalent biopharmaceutical expression system and has been proven safe for commercial production of protein therapeutics (1). However, even after multiple purification steps, biopharmaceuticals contain residual host-cell protein (HCP) impurities that pose a potential safety risk to patients (2). Health authorities demand close monitoring of HCP impurities and require sensitive analytical methods with high coverage: the ability to detect a broad range of HCP impurities (3, 4). Polyclonal sandwich immunoassays are…

Regulation, Analytical, and Process Issues with Leachables: Toward Harmonization for Latin America with Europe and North America

The pharmaceutical industry follows strict regulations regarding impurities, including process-related leachates. Plastic manufacturers use hydrophobic, nontoxic additives for manufacturing containers for use in the pharmaceutical and food industries. However, some issues about dealing with such impurities are not yet resolved. In developing countries, regulators are working on guidelines to help local companies ensure characterization of impurities. In this exclusive editorial eBook, authors from Mexico describe some issues related to plastic leachables in the context of ongoing efforts to harmonize regulations…

Aggregation from Shear Stress and Surface Interaction: Molecule-Specific or Universal Phenomenon?

Exposure to solid–liquid and air–water interfaces during production, freezing and thawing, shipment and storage of protein therapeutics may be a contributing factor in their degradation (e.g., aggregation, fragmentation) (1, 2). Surface exposure, particularly during manufacturing processes, often is accompanied by various degrees and durations of shear stresses originating from fluid flow and acting on proteins at interfaces. The magnitude and duration of shear rates depends on velocity gradients within each solution and varies significantly among manufacturing steps. On the low…

Strategies for Successful Sample Transfer

Nadine Ritter is president and senior analytical advisor of Global Biotech Experts, LLC and a long-time member of BioProcess International’s editorial advisory board. At a recent CASSS North American CMC Strategy Forum called “Methods on the Move: Addressing Method Transfer Challenges,” she discussed the biopharmaceutical industry’s logistical challenges of analytical test samples for drug substances and products. At the conference, BPI’s editor in chief Anne Montgomery met with her to discuss some key points of this topic. Logistics Challenges Montgomery:…

Enabling Faster Workflows with Protein Purification Technologies: Improvements in Chromatography and Electrophoresis

Purification of recombinant proteins is a critical step during protein therapeutics development. Protein therapeutics have a number of classifications based on their potential applications, including use as vaccines and diagnostics as well as for enzymatic, regulatory, or targeting activities (1). For all such applications, identifying and verifying protein purity is most important. Whether proteins themselves are therapeutics or the target proteins of interest, effective purification is essential in drug development. Since the introduction of recombinant proteins in the early 1980s,…

Evolving Bioassay Strategies for Therapeutic Antibodies: Essential Information for Proving Biosimilarity

The modern age of biologics began 35 years ago with the approval of Lilly’s Humulin product — a biosynthetic form of human insulin derived from recombinant DNA and microbial cell culture (1). Today, about a quarter (27%) of the drugs approved yearly by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) are biopharmaceuticals: primarily monoclonal antibodies (MAbs), but also vaccines, blood products, and (recently), advanced therapies based on genes and cells. A decade ago, the average…

Buffers in Biologics Manufacturing

Biotechnology has enabled commercialization of protein-based drugs including insulin, growth factors, blood factors, and antibodies. Production and purification of such biologic products require different buffers for pH control and stabilization of reactions in different steps during biomanufacture. These processes include cell culture production (the “upstream” phase), purification (the “downstream” phase), and a final phase in which excipients are introduced to the drug substance to create a drug product (“formulation and storage”). In upstream processes, buffers are primarily used for their…

Residual Host-Cell DNA in Biopharmaceutical Products: 96-Well Plate-Based Extraction and Real-Time PCR Assay for Quantitative Measurement

Regulatory guidelines that cover the development of biopharmaceutical products require testing of host-cell deoxyribonucleic acid (DNA) impurities. Real-time polymerase chain reaction (PCR) has become a popular technology for DNA quantitation and monitoring of process impurities associated with biomanufacturing. One critical challenge associated with host-cell DNA impurity testing is that recombinant proteins (e.g., monoclonal antibodies, MAbs) and their corresponding buffer components often interfere with DNA quantitation in real-time PCR reactions (1, 2). Some sample types do not require a full extraction…

A Statistical Approach to Assess and Justify Potential Product Specifications

As stated in ICH Q6B, specifications are critical quality standards that are both proposed and justified by drug product manufacturers. Xiaoyu et al. provide information on several statistically based strategies to establish specification acceptance criteria (SAC) (1). Here we address an alternative approach to relate proposed SAC for quantitative data to relevant lot history. In particular, proposed SAC can be derived in part by using calculated limits for which the lower bound of an approximate 95% confidence interval for the…