Upstream Processing

Are “Land Mines” Hiding in Your Supplier Records?

    A growing trend in US Food and Drug Administration (FDA) warning letters has been citations for “no justified rationale.” Since 2004, warning letters taking companies to task for poorly documented decision-making and risk-assessment practices has more than doubled — from two in 2004 to four in 2008 and five in 2009. These citations are always in relationship to risk-based decisions: sampling (what, how often, and how much), nonconformances and corrective/preventative actions (when is “root cause” actual root cause,…

Is Bovine Albumin Too Complex to Be Just a Commodity?

    Albumin is the most abundant serum protein. It serves several functions in vivo: e.g., binding and transport of fatty acids, hormones, and metal ions; maintenance of osmotic pressure and pH; and binding of exogenous toxins and products of lipid oxidation (1). Over time, development of large–scale purification methods have translated those functions into diagnostic, cell culture, and microbiological applications. It is important to note, however, that purification procedures can promote molecular changes and thereby add to the already…

Changes in Raw Material Sources from Suppliers

    Maintaining the supply chain of single-source raw materials is of utmost importance for a biopharmaceutical company’s manufacturing operations. As often happens, a supplier will notify its customer of process changes that might affect the quality or properties of supplied materials. Occasionally, a supplier might notify the customer of substitutions in its own supply chain or other changes in the source of its own raw materials. Customers must conduct appropriate testing using the “new” raw material(s) to ensure acceptable…

Is Bovine Albumin Too Complex to Be Just a Commodity?

    For decades, the complexity of albumin has been researched extensively, yet many manufacturers and users of the protein have treated it more as a commodity. Because albumin has been readily available, suppliers and purchasers alike have frequently relied on more obvious measures of “purity” and other minimal release criteria to make their decisions. If a lot does not perform well in practice, the typical supplier’s response has been to investigate the manufacturing process for deviations, then correct them…

Improved HCP Quantitation By Minimizing Antibody Cross-Reactivity to Target Proteins

    Host cell proteins (HCPs) are process-related impurities derived from a host cell expression system that may be present in trace amounts in a final drug substance. During biologics development, it is important to demonstrate that a bioprocess is efficient in removing HCPs and that it provides consistent control of HCP levels. Several techniques are typically used for detection, quantitation, and risk evaluation of HCPs in biologics. The most common are enzyme-linked immunosorbent assays (ELISAs), Western blotting, sodium-dodecyl-sulfate polyacrylamide…

Nutrient Supplementation Strategies for Biopharmaceutical Production, Part 3

    Scale-up studies are needed for assessing cell culture production system options and for testing nutrient supplementation techniques as well. With the many supplementation options available, choices need to be made as early in product development as possible because advantages can change with scale. One published fed-batch scale-up study testing from 3 L up to 2,500 L highlights items to be considered in addition to the nutrient supplementation process such as the impact of pH and CO2 control (1).…

A Risk-Based Aproach to Establishing Animal-Component–Free Facilities

Bovine spongiform encephalopathy (BSE) and its potential to affect humans emerged as a concern in the 1990s. So suppliers of many essential animal-sourced components used in cell culture and fermentation processes became concerned about the potential for material contamination with prions. Viruses also can be present in raw materials derived from animal origins. Many important drug and vaccine products are made by mammalian cell culture or bacterial fermentation, so their biological safety is paramount. However, it is very difficult to…

Accelerating Bioassay Transfer in a GMP Environment

Most products in discovery by pharmaceutical companies today are biopharmaceuticals. Made by living organisms, these are typically large–molecular-weight products that rely on their secondary and tertiary structure for therapeutic effectiveness. Synthetic small molecules and biopharmaceuticals both require analytical verification for release, but only biopharmaceuticals require functional potency assays for investigational new drug (IND), biological license application (BLA), and new drug application (NDA) submissions. Those activities often require elaborate transfers of diverse, biological, product specific assays that carry greater chances of…

Using In Vitro Assays for Therapeutic Enzyme Characterization

A number of biopharmaceuticals are enzymes that act in vivo on high-molecular substrates. It can be a challenge to develop in vitro methods for accurately assessing their biological activity. Interest is also developing in using enzyme kinetic parameters as product quality attributes under the quality-by-design (QbD) initiative. Among biotechnology therapeutics, the conventional method of expressing potency is in units/mg of biopolymer. For enzymes, a unit of activity was defined in 1958 by the International Union of Biochemistry and Molecular Biology…

Nutrient Supplementation Strategies for Biopharmaceutical Production, Part 2

Some of the numerous feeding strategies are more appropriate than others for certain types of cell culture production systems. Once a nutrient supplement has been identified as described in Part 1 of this three-part review (1), a supplementation strategy must be chosen. Supplementing at too great a rate may expose log-phase cells to stresses such as increased osmolality and lactate levels that would inhibit biomass expansion. But inadequate supplementation can lead to early apoptosis through rapid depletion of selected important…