Biopharmaceutical companies are constantly evaluating new methods for mammalian cell line development that provide benefits such as shorter timelines, improved consistency, higher production, better genetic stability, and increased flexibility. Each of these advantages extends a large cost benefit to companies as their recombinant protein products are moved from development into the clinic and finally to commercial launch. A versatile system has been developed that is capable of transferring genes of interest into a wide variety of mammalian host cells and offers a number of the above advantages over other methods. The system, which is referred to as GPEx™ (an acronym for “gene product expression”), utilizes replication-defective retroviral vectors, derived from Moloney murine leukemia virus (MLV) and pseudotyped with vesicular stomatitis virus G protein (VSV-G), to stably insert single copies of genes into dividing cells…
Category: <span>Biologics Production</span>
Biopharmaceuticals are predicted to become the main driving force of the pharmaceutical market in the near future. Other than blockbuster products such as erythropoietin, an increasing number of approved recombinant therapeutic proteins are based on antibody technology (e.g., fusion proteins or monoclonal antibodies [MAbs]). In contrast to relatively simple products produced in Escherichia coli bacteria (e.g., insulin), proteins which require complex posttranslational modifications such as glycosylation have to be produced in eukaryotic cells. In this context, production systems have been dominated by mammalian cell culture. Nevertheless, alternative eukaryotic expression technologies based on yeast, insect cells, transgenic animals, or transgenic plants are under development. Plants are a particularly promising alternative to mammalian cell culture because of their excellent safety aspects and estimated cost-efficient upstream/cultivation processes. In addition, plants are well known for their ability to express biologically functional monoclonal antibodies. In comparison to the seed plants most widely used for transgenic protein expression — tobacco, corn, and rice — mosses provide unique, beneficial features…
Psoriasis is a chronic, inflammatory disease of the skin that is estimated to affect 2-3% of the U.S. population. The estimated annual outlay for treating the disease has ranged from $1.6 billion to $3.2 billion, and the cost to individuals with the disease is far higher than the monetary costs. Psoriasis is characterized by excessive keratinocyte proliferation, leading to a significant thickening of the epidermis, expansion of epidermal rete pegs into papillary dermal space and abnormalities in the differentiation process. Clinically, one sees red, raised, scaly lesions that can occur over any part of the body. The etiology of the disease is complex and not well understood. T-cells are almost certainly involved in the initiation and maintenance of psoriatic lesions. Although the triggering event is immunological, alterations in keratinocyte function also appear to be important to the overall pathophysiology…
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…
The Vmax™ technique has been used extensively to estimate filter area requirements for normal flow filtration (NFF) processes in biopharmaceutical applications. The benefits that this technique presents over conventional flow decay methods are the speed of testing, reduced volume requirements for evaluation, and competitive testing of varying filter types/sizes — all of which present an optimized filter screening strategy and preliminary estimate of optimized filter size requirements. Filter size or filtration area requirements derived using the Vmax technique consist of contributions from both capacity and flow-time aspects of the filtration process. This article examines the relative contributions of these terms to overall filter sizing vis-à-vis the ease of fluid filterability…
The diversity of the antibody-antigen interaction and our ability to manipulate this interaction has created an enormous potential for the discovery and development of IgG therapeutics and diagnostics. Along with the expanding clinical pipeline of antibody products, increasing efforts have been devoted to improving antibody production and purification procedures. In order to meet drug discovery needs with limited resources, the so called “flexible generic purification scheme” approach has been adopted to develop a robust manufacturing process that allows the application of similar operational conditions to different monoclonal antibody molecules…
Current expression technologies have enabled the production of thousands of recombinant proteins in diverse production hosts. Therapeutic recombinant proteins have been engineered for a variety of purposes including reduced antigenicity, longer half-life, simplified process development, and increased affinity. Protein engineering has relied on various high throughput methods (e.g., directed evolution, phage display) to identify candidate proteins with the desired therapeutic properties. The physiological and biochemical diversity of native and engineered proteins reflects on the abundance of production hosts, expression tools, and different approaches for protein purification. Notably, a key step in high-throughput protein production is purification, which is a bottleneck where large numbers of samples are involved. Universal purification methods that can be applied to virtually any protein, and that are amenable to automation, can be used to address this problem…
Since the mid-1970’s, when Kohler and Milstein first discovered the process by which myeloma cells and splenocytes could be fused to produce monoclonal antibodies (MAbs), a whole new world of important therapeutic, prophylactic and diagnostic products has opened up, bringing in huge benefits for patients and manufacturers. The total sales of therapeutic MAbs reached more than $13 billion in 2005. Sixteen of the 18 FDA-approved MAbs came to the market after 1997, and over 150 are currently in clinical development, suggesting their increasing medical importance and the remarkable, recent advancements in development technology…