Vaccine presentations and delivery technologies--what does the future hold?

Abstract

There is an urgent need to change the presentations and delivery technologies of current vaccines. Until recently, these factors had not been key criteria in the selection of vaccines for program use. Recent and current changes in the field of vaccines and their delivery lead the authors to postulate that a major paradigm shift will take place over the next decade to revolutionize vaccine presentation and delivery in national immunization programs. The programmatic needs for certain vaccine presentations will increasingly dictate elements of vaccine development and manufacture. Over the next decade, an inexorable drift towards firstly, single-dose preparations, and secondly, delivery technologies other than the conventional needle and syringes is anticipated. A unified system capable of delivering multiple antigens as a single dose is urgently needed; however, changing the status quo of vaccine manufacture is not easy. The market predominantly produces vaccines delivered by needle and syringe. Profits for manufacturers from sales to developing countries are marginal at best, and there is little financial incentive to change. Global leaders will need to take bold decisions and begin demanding vaccines which have a presentation that lends them to safer, more practical delivery systems. If a strong enough case can be made to restructure the vaccine manufacturing industry, either through market forces, global bodies, such as the World Health Organization and the United Nations Children's Fund, or both, a dramatic change could be brought about that will make vaccine delivery simpler and safer. A globally coordinated approach to funding research and the introduction of a multiple-antigen, single-dose delivery system is urgently needed. The needs are clear, and this review argues that if the case is presented strongly enough, the resources will be found.