ORAL DELIVERY OF VACCINES - FORMULATION AND CLINICAL PHARMACOKINETIC CONSIDERATIONS

In recent years, there has been a gradual acceptance of the important role of sIgA in protecting mucosal surfaces against infection with a wide range of pathogenic organisms. Since sIgA is most efficiently stimulated by local application of antigens, there has been an increasing emphasis on the role of oral immunisation. The numerous advantages of the oral route over alternative routes of administration has driven the search for effective vaccines, often despite disappointing results. Nevertheless, recent developments in recombinant DNA technology and in the formulation of antigen delivery systems have given rise to justified optimism that the next decade will see the development of several new and improved oral vaccines (table IV). These vaccines will undoubtedly come to play an important role in preventing diseases caused by a number of pathogenic organisms which are currently poorly controlled. New oral vaccines are likely to be particularly beneficial in the Third World, where intestinal infections still cause a massive toll of preventable deaths. Because of the existence of the common mucosal immune system, new oral vaccines also offer the promise of control over several sexually transmitted diseases for which there are no vaccines currently available. © 1992, Adis International Limited. All rights reserved.