One of the major concerns facing relatively young biotechnology companies once a lead product has been identified is the issue of manufacturing. Usually this involves the upscaling of a lab-scale process while at the same time, complying with good manufacturing practice (GMP) to ensure a reproducibly-produced and consistent product. It also involves the establishment of specific and robust assays in process controls and release criteria. This issue has become more acute in the EU since 2004 due to the EU Clinical Trials Directive requiring GMP-certified production of investigational medical products even for phase I trials. Startup biotech companies are often limited in their finances and resources, as well as being bound by tight milestones. Quite often the expertise in upscaling and GMP-compliant production as well as the facilities and equipment required are not available in-house…
Tag: <span>scale-up</span>
The aim in process filtrations is to purify the liquid preparation by removing particulate impurities while obtaining as large a throughput as possible under practical conditions. The rate of flow should be expeditious enough to meet time constraints when necessary. This places a focus on the applied differential pressure level that motivates the liquid flow. A balance must be sought. Higher differential pressures increase the flow rates but may decrease throughputs by compaction of the filter cake. Also, higher applied pressures may minimize the adsorptive retention of particles. Deciding which is the proper filter involves small-scale filtration trials. The choice of the filter having been made, its size, in terms of the area necessary for the processing of the production batch, is arrived at by extrapolations from the small-scale tests that were performed…
Baculovirus, particularly AcMNPV (Autographa californica multiple nucleocapsids polyhedrosis virus), is widely used for heterologous protein expression. There are several shortcomings in the current practice of preserving and scaling up baculovirus: 1) extracellular baculovirus stocks, routinely prepared in large volumes and stored at 4º C, are often unstable; 2) laborious and time-consuming steps to amplify and titer the baculovirus stocks are often necessary, and generally recommended, for achieving consistent viral infection and protein expression; 3) once prepared, the baculovirus is suspended and stored in conditioned medium. Given the complex, undefined, and unstable nature of the spent media components, including proteases and nucleases, protein expression tends to vary even when steps are taken to titer the virus stock and adjust the amount of stock used for infection. Here, we will report a new method for preserving and scaling up baculoviruses that: 1) provides a new form of viral stock more stable than the traditional, extracellular stock; 2) eliminates the need for virus amplification and retitering; 3) drastically reduces the turn-around time and resources required for scale-up; and 4) improves yield and consistency in protein expression.
A number of antibody drugs are currently in clinical development and 22 antibodies (including five diagnostic antibodies) have received FDA market approval in the last decade. A number of different technologies are now being used successfully to isolate potent therapeutic antibodies with minimal immunogenicity and improved safety. These include chimerisation (mouse/human antibodies), humanisation (complementarity-determining region [CDR] grafting), transgenic mice, phage display, ribosome display, and other emerging technologies. The phage and ribosome display technologies used at Cambridge Antibody Technology (CAT) are based on the physical linkage of gene to gene product which enables the recovery and enrichment of genetic material encoding the selected antibody…
The developing biotechnology community may offer solutions and hope for recent world events that have focused attention on the vulnerability of the world’s population. Concerns about new pandemics have been raised by the emergence of new influenza strains and the re-emergence of older and even more highly virulent strains. In addition, there are fears that bioterrorism could involve agents such as anthrax or smallpox, and these threats become even more of a concern when you consider the increased mobility of such organisms via today’s commercial aviation. The ability of the biomedical community to respond rapidly to these shifting threats is more important than ever…
The baculovirus expression vector system, which is based on infecting insect cells with recombinant Autographa californica nuclear polyhedrosis virus (AcNPV), is one of the most commonly used eukaryotic expression systems aimed at producing functionally active mammalian proteins. It offers advantages such as high-level protein expression and post-translational processing capabilities that are extremely important to the biological activity of certain proteins. This system utilizes a strong promoter of the very late gene, polyhedrin, to drive heterologous protein overexpression. Nevertheless, in order to generate milligram amounts of recombinant proteins, cell culture often needs to be scaled up to as much as 25 liters….
Today concentrated efforts are underway to improve the bioactivity of therapeutic proteins with the aim of reducing: (i) the number and concentration of the applied doses of the therapeutic protein, (ii) undesired side effects, and (iii) the cost of a therapy. A very promising strategy is to optimise the glycosylation of these biotherapeutics. A novel expression platform, GlycoExpressâ„¢, has been developed to produce proteins with fully human glycosylation, optimised sialylation, and improved bioactivity…
It has been reported that the biotechnology-derived medicines area of the pharmaceutical industry led to 133 marketed entities with sales of $22 billion by the year 2001. By 2002, the therapeutic protein market had reached $32 billion, with biologics representing more than 50 percent of all drugs approved by FDA — up from a modest 16 percent in 1995. The biopharmaceutical market is predicted to grow to $50 billion by 2008. Currently, approximately 40 percent of biopharmaceutical products are in Phase I and Phase II clinical trials. It is anticipated that from 2003 to 2008 there will be a more than 45-fold increase in demand for access to product development facilities capable of supplying clinical material…
Proteins and their promise for revolutionizing drug discovery have come virtually full circle in just a few decades. The advent of genetic engineering and the emergence of early recombinant proteins such as insulin and interferon dramatically boosted the perceived value of proteins in pharmaceutical research and of protein drugs in particular. Although the lights dimmed somewhat on the promise of therapeutic proteins in subsequent years, more recent times have seen a resurgence of interest in proteins, particularly monoclonal antibodies. Perhaps most telling has been the dawn of the post-genomic era, which has cast a bright spotlight on proteins, long respected as the work-horses of the cell, for their usefulness in exploring cell function, unraveling biochemical pathways, understanding disease, and for their massive value as novel drug targets…