Translational research to assist policy decisions about introducing new vaccines in developing countries.

Few new-generation vaccines have found their way into public-health programmes for the poor in developing countries, and for those that have, delays of years or even decades after their licensure and introduction in industrialized countries have been the rule. Financial constraints and political obstacles have played major roles in delaying the introduction of the vaccines. Also contributing to this situation has been a dearth of needed research. While past analyses have identified inadequate support for conducting Phase 1 studies as an obstacle, other types of translational research are also needed. Vaccines may perform less well in impoverished populations in the developing world than in more affluent populations. Consequently, Phase 2 and Phase 3 trials of new vaccines in developing countries are a second essential type of translational research needed for the introduction of vaccines in developing countries. Moreover, even for vaccines that have performed well in pre-licensure human trials in developing countries, doubts often remain about whether the local disease burden justifies introduction of vaccine, whether the vaccine will be cost-effective, and whether introduction of vaccine will be programmatically feasible, acceptable, and financially sustainable. Because these residual doubts constitute obstacles to the introduction of vaccine, a third type of translational research is needed to provide this evidence required for policy. In this paper, these three types of translational research are illustrated with projects being undertaken in the Diseases of the Most Impoverished Programme. The Programme is conducting translational research to accelerate the rational introduction of new vaccines against cholera, shigellosis, and typhoid fever in developing countries affected by these diseases.