Biochemicals/Raw Materials

Activatable Immunoconjugates for Target Cancer-Cell–Specific Diagnosis and Therapy

In cancer treatment, early diagnosis and targeted therapies are assumed to yield the highest cure rates. However, most current methods are limited by their low sensitivity to early disease and a lack of specificity for targeted cell killing. Newly developed, activatable immunoconjugates assist in the accurate detection of cancer through in vivo imaging with high target-to-background contrast (1,2). They also provide for the possibility of highly specific, light-mediated treatment with minimal effects on healthy cells surrounding tumors (3). In fact,…

Powders and Bulk Liquids

    The two major bioprocess fluids — culture media for upstream production and buffers for downstream processing — are classic single-use products. They are used once and then disposed of. The two basic options for both differ by physical state: powdered media and buffers (“powders” for in-house preparation of liquids by end users) and bulk liquid culture media and buffers, which are fully prepared by their suppliers (“liquids”). We conducted market research studies comparing the benefits and risks (value…

Effective Cryopreservation and Recovery of Human Regulatory T Cells

The list of conditions being targeted by cell therapies is rapidly growing, but commercializing cells for widespread medical use will require standardized laboratory practices. Development processes must be adapted specifically for cell-based drug products. Regulatory T-cell therapy represents a promising new frontier in the immunotherapy of autoimmune disorders, especially for patients who have been refractory to available treatments. Because of intrinsic fragility, cell therapy products can be highly sensitive to variations in manufacturing procedures. Standardization of drug-product cryopreservation and storage…

IgM Purification with Hydroxyapatite

Hydroxyapatite (HA) has a long and successful history in the field of antibody purification, and it has worked well for immunoglobulin M (IgM) monoclonal antibodies (MAbs) (1,2,3,4,5,6,7,8). Applications range from initial capture to intermediate purification to final polishing. HA is best known for its superior ability to reduce antibody aggregates, but it also supports excellent reduction of DNA, viruses, and endotoxins. As IgM MAbs exhibit increasing potential in the fields of cancer and infectious disease and in stem-cell therapies, HA’s…

Accounting for the Donnan Effect in Diafiltration Optimization for High-Concentration UFDF Applications

The biopharmaceutical industry is targeting high-concentration protein formulations to enable subcutaneous administrations. Such administration can provide better patient convenience than intravenous administration. One challenge associated with high-concentration formulations is increased electrostatic interaction between proteins and excipients. That is a result of increased protein-charge density at high protein concentrations. Such interactions can create an offset between excipient levels in final products and diafiltration buffers in ultrafiltration processes. The effect of such electrostatic interactions in a membrane process is known as the…

Analysis By Size and Charge

An early BPI Lab article addressed the power of liquid chromatographic separations for biopharmaceutical laboratory use (1). Such techniques separate biomolecules based on a number of different properties: size, solubility, hydrophobicity/-philicity, binding affinity. The next most powerful means of separation — and thus high-resolution identification — of nucleic acids and proteins/peptides is based primarily on electrostatic properties: electrophoresis. Although it doesn’t really work in a process or preparative setting, it is a fundamental technique in modern biopharmaceutical laboratories, where it…

Impact of Process Interruption on Virus Retention of Small-Virus Filters

Manufacturers of biopharmaceuticals using mammalian cell culture must have processes in place to minimize the likelihood of virus contamination of their products. Regulatory agencies provide guidelines for testing strategies and best practices to assure raw-material safety and control of the manufacturing process. Safety assurance relies on an interdependent matrix of managed risks, including characterization and control of raw materials, extensive testing of process intermediates, and demonstration of the virus removal capabilities of purification unit operations Figure 1:  () A dedicated…

Emerging Challenges to Protein A

Protein A affinity chromatography has been a target for replacement since its commercial debut, mainly because of its high acquisition cost. The technique became established despite the cost because it was born into an industrial culture that favored speed to market over manufacturing economy (1). Vendors have since strengthened protein A’s position with incremental but worthy improvements such as higher capacity, lower ligand leaching, and modest tolerance of NaOH. Collateral improvements in polishing technologies, such as the high throughput and…

Virus Risk Mitigation for Raw Materials

Recombinant protein–based medicinal products and modern cell-based vaccines have a very strong safety history with respect to viral and microbial contamination. However, virus contamination incidents do occur occasionally in manufacturing processes, and they can consume many resources and be expensive to rectify. The root cause of contamination incidents in recent years is most likely the use of contaminated raw materials. These include bovine serum contaminated with reovirus, epizootic hemorrhagic disease virus, Cache valley virus or vesivirus 2117; porcine trypsin contaminated…

Protein A

The number of blockbuster monoclonal antibody (MAb) drugs continues to grow. In 2008, MAbs generated revenues in excess of US$15 billion (1), making them the highest-earning category of all biotherapeutics. The world MAb market will reach $62.3 billion in 2015, with next-generation therapeutic antibody revenues reaching $2.3 billion in 2015 according to Visiongain reports published in September and November 2011 (2, 3). Biosimilar antibodies will also begin to enter established markets as regulatory authorities clear approval pathways for them. Most…