What are today's orphaned vaccines?

Development costs for new biological agents are increasing, and the time span from laboratory research to introduction of a product on the world market is becoming ever longer. Complex regulatory requirements add barriers and additional costs to early introduction abroad. This results in reluctance by manufacturers to undertake development of a vaccine that will be used for a tropical disease in only the public sector of a poor country. The chances of recovery of huge investment costs before patents expire are not good, unless such a new vaccine can also be sold at high cost in North America and Europe. These are some of the reasons that we still do not have a modern Japanese encephalitis vaccine or products against malaria and dengue fever. Many tropical countries must find a way to develop their own vaccine production facilities. Innovative help for technology transfer will have to be forthcoming, or many new life-saving products will never bridge the gap between research unit and production.