ABSTRACT
HPV disease is a global disease of interest to many countries.5 The first-generation vaccines are licensed in over 100 countries and widely recommended,12 and the same was anticipated for the 9vHPV vaccine. Therefore, the 9vHPV vaccine clinical development program was designed to involve many regions of the world. The pivotal efficacy study V503-001 was an international, multiregional, multicenter study, an approach that allowed the enrollment of a diverse population of subjects from developed and developing countries, thereby enhancing the generalizability of the study results. However, conducting a large multiregional trial presents a variety of challenges: (1) Consistent quality of the study must be maintained across regions with particular attention to preserving homogeneity in subject enrollment criteria, and the collection, handling, and testing of biological samples used in the evaluation of study endpoints across regions and study sites; (2) local health authorities may require specific analyses to support licensure, such as subanalyses in the local population; and (3) regional differences in epidemiology of HPV disease and prevalence of HPV types may impact the overall incidence of disease endpoints in the study and complicate the interpretation of the results. The goal of this chapter is to discuss how these challenges were addressed.
