Veterinary applications vaccines

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). 

Although it is one of the most potent adjuvant substances known, FCA is too toxic for human use. Some of its reported side effects are listed in Table 10.21. Its toxicity has also precluded its routine veterinary application, although it is sometimes used for experimental purposes. FIA is less toxic than its mycobacterial-containing counterpart. It has found used in the preparation of selected animal vaccines, and was even incorporated into some earlier human vaccines (Table 10.22). However, its use in humans (and to a large extent, animals) has been discontinued due to its reported toxic effects. 

Jalava K, Hensel A, Szostak M, et al. Bacterial ghosts as vaccine candidates for veterinary applications. J Control Release 2002 85 17-25. 

Eloss, D.M., Falkenburg, D., and Conrad, U. (2007) Production of vaccines and therapeutic antibodies for veterinary applications in transgenic plants an overview. Transgenic Res., 16, 315-332. 

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. 

M. F. Tatner, Fish vaccines, in Vaccines for Veterinary Applications, ed. A. R. Peters, Butterworth-Heinemann Ltd, Oxford, 1993, pp. 199-224. 

The application of vaccine technology forms a core element of modern medicinal endeavour. It plays a central role in both human and veterinary medicine and represents the only commonly employed prophylactic (i.e. preventative) approach undertaken to control many infectious diseases. The current (annual) global vaccine market stands at in excess of US 3 billion. Immunization programmes, particularly those undertaken on a multinational scale, have served to reduce dramatically the incidence of many killer/disabling diseases, such as smallpox, polio and tuberculosis. 

Rudbach, I, D. Johnson, and I Ulrich, Ribi adjuvants chemistry, biologyand utility in vaccines for human and veterinary medicine, in The Theory and Practical Application of Adjuvants, S.-T. Des, ed. 1995, New York Wiley. 287-13. 

What, for example, should be the "active principle" A vaccine may be used to prevent infections or only to avoid the appearance of clinical symptoms and to inhibit the spread of the microorganism. A new molecule may affect several physiological mechanisms and could be useful for several indications or applications. A veterinary product could be useful in several species and for different purposes. Different approaches, methods, models and most likely also collaborating specialists may be required to address these options. 

With whole-herd applications of antimicrobial and antiparasitic substances and live vaccines in mind, ecotoxicity assessments have been included in the registration reqirements for veterinary products in the EEC and the USA. A defined procedure exists in the USA where a "Finding of no significant impact" (FONSI) certificate by the Animal and Plant Health Inspection Service (APHIS) is a necessary prerequisite for the registration. 

The application of the same basic and formal principle to all biological products, including inactivated vaccines appears exaggerated. However, Commission Directive 92/18/EEC describes the same principle of a basic assessment ("shall always be carried out"), followed by ecotoxicity tests in the case of "potential exposure of the environment" also under Title II, which is specific for immunological veterinary medicinal products. 

Preclinical Results and Clinical Applications. Both pDNA- and mRNA-based vaccinations were demonstrated to be efflcacious in animal models as prophylactic or therapeutic immunotherapies against tumors, infectious diseases, and allergy. Two pDNA-based vaccines are commercialized for veterinary use an anti-equine fever and an anti-infectious hematopoietic necrosis virus (IHNV) for farm-raised salmons. In humans, several formulations of nucleic acid vaccines are tested in clinical trials (see the actualized list of trials at www.clinicaltrials.gov). Although pDNA-based vaccine trials were reported in the context of antitumor, antivirus (HIV, influenza virus, HBV) and antiparasite Plasmodium falciparum) approaches, mRNA-based vaccines were up to now tested only as immunotherapies against cancer (review by Liu and Ulmer for pDNA [35] and Pascolo for mRNA [36]). 

In comparison to current vaccine R D projects, the number of newly Kcensed vaccines is extremely small. Most newly licensed products are improvements or combinations of existing vaccines real vaccine novelties are very rare. Thus, the chances that a vaccine project in advanced research finally ends up as a vaccine product is minimal and is certainly far below 1%. These low success rates in research inevitably lead to long research phases. Short time intervals of around five years between the first publication or patent application of a new vaccine concept and the start of full development are an extremely short, applied research phase for vaccines. These may be applicable to some veterinary vaccines, for which vaccine... 

Some vaccines also have applicability for diseases of domestic animals (eg, Rift Valley fever and Venezuelan equine encephalitis). In addition, vaccines are provided to persons who may be occupation-ally exposed to such agents (eg, laboratory workers, entomologists, and veterinary personnel) throughout government, industry, and academe. 

The recent studies on applications of chitosan and its derivatives as adjuvant/delivery systems for veterinary vaccines are summarized in Table 33.1. 

Application of Chitosan for Vaccine Delivery in Veterinary Medicine... 

Many compounds with adjuvant activity are presently known (shown in Table 12.2) but only a few are applied routinely in human and veterinary vaccines. The application of the novel adjuvants are limited for several reasons, such as disappointing efficacy in the target animal species, insufficient safety, problems with large-scale preparations, and limited stability of the final formulations. Many studies have reported on O/W and W/O emulsions used as adjuvants and delivery systems for immunization (Hilgers et al., 1994a, b, 1999). The adjuvanticity of the W/O/W makes this type of multiple emulsion a suitable delivery system for immunization with prolonged release, and its interesting preparation is presented below. 

Application of orally administered organogel has been extended to a veterinary study, where chickens were vaccinated against Newcastle disease via raw rice... 

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