Veterinary biopharmaceuticals

Although most biopharmaceuticals approved to date are intended for human use, a number of products destined for veterinary application have also come on the market. One early such example is that of recombinant bovine GH (Somatotrophin), which was approved in the USA in the early 1990s and used to increase milk yields from dairy cattle. Additional examples of approved veterinary biopharmaceuticals include a range of recombinant vaccines and an interferon-based product (Table 1.7). 

While the majority of pharmaceuticals produced by modern biotechnological means are destined for human use, several veterinary biopharmaceuticals have also gained approval (Table 10). One of the earliest... 

Table 1.7 Some recombinant (r) biopharmaceuticals recently approved for veterinary application in the EU...

Clinical trials serve to assess the safety and efficacy of any potential new therapeutic intervention in its intended target species. In our context, an intervention represents the use of a new biopharmaceutical. Examples of other interventions could be, for example, a new surgical procedure or a novel medical device. Veterinary clinical trials are based upon the same principles, but this discussion is restricted to investigations in humans. Clinical trials are also prospective rather than retrospective in nature, i.e. participants receiving the intervention are followed forward with time. 

In order to overcome environmental concerns in particular, some companies are investigating the use of engineered plant cell lines as opposed to intact transgenic plants in the context of biopharmaceutical production. One company (DowAgroSciences) gained approval in 2006 for a veterinary subunit vaccine against Newcastle disease in poultry produced by such means. 

Since risk analysis plays an important role in public policy decision making, efforts have been made to devise a means by which to identify, control, and communicate the risks imposed by agricultural biotechnology. A paradigm of environmental risk assessment was first introduced in the United States by Peterson and Arntzen in 2004. In this risk assessment, a number of assumptions and uncertainties were considered and presented. These include (1) problem formulation, (2) hazard identihcation, (3) dose-response relationships, (4) exposure assessment, and (5) risk characterization. Risk assessment of plant-made pharmaceuticals must be reviewed on a case-by-case basis because the plants used to produce proteins each have different risks associated with them. Many plant-derived biopharmaceuticals will challenge our ability to define an environmental hazard (Howard and Donnelly, 2004). For example, the expression of a bovine-specihc antigen produced in a potato plant and used orally in veterinary medicine would have a dramatically different set of criteria for assessment of risk than, as another example, the expression of a neutralizing nonspecihc oral antibody developed in maize to suppress Campylobacter jejuni in chickens (Peterson and Arntzen, 2004 Kirk et al., 2005). 

Transgenic plants present enormous potential to become one of the most cost-effective and safe systems for large-scale production of proteins for industrial, pharmaceutical, veterinary, and agricultural uses. Over the past decade, much progress has been made with respect to the development of vaccines, antibodies, and other therapeutic proteins. Biopharmaceuticals in Plants Toward the Next Century of Medicine provides a comprehensive survey of ail major aspects of the development and production of plant-made biopharmaceuticals. 

The objectives of this chapter are to give aspiring formulation scientists a brief yet useful and meaningful overview of conventional parenteral technology as it is applied today and the development of new delivery systems of biopharmaceutical drugs to yield successful, sterile parenteral products for human and veterinary use. 

Poultry, Applying the Biopharmaceutics Classification System to Veterinary Pharmaceutical Products (in 2 Parts), Vaccine Development, Immunological Aspects of Controlled Antigen Delivery, Pharmaceutical Challenges in Veterinary Product Development 2002 In Situ Forming Injectables, Bacterial Ghosts, 19... 

In the EU, the development of medical products for human and veterinary use is governed by a variety of laws, legislations, directives and guidelines, some of them have very specifically developed for biopharmaceuticals. The market value (at exfactory prices) of the total EU pharmaceutical market is just over Euro 62000 million (i.e., approximately 30% of the world market) its retail value now exceeds Euro 90000 million. In 1997, the pharmaceutical industry employed nearly 500000 people within the EU, including 71000 in R D. In addition to a substantial R D-based sector, the pharmaceutical industry in Europe also has active sectors dealing in generic (i.e., patent-expired) and OTC medicines. 

This chapter reviews applications of chitosan for its bioactive properties and in veterinary drug/ vaccine delivery, and also discusses possibilities and limitations in regard to biopharmaceutical aspects. The properties of chitin and chitosan expected to enhance the therapy in veterinary medicine will be conferred and the future research directions in this field will be indicated. 

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