Sanofi announces dengue vaccine candidate Phase III study meets primary endpoint Sanofi Pasteur, the vaccines division of Sanofi, announced that the first of two pivotal Phase III efficacy studies with its dengue vaccine candidate has achieved its primary clinical endpoint. The efficacy study showed a significant reduction of 56% of dengue disease cases. Initial safety data are consistent with the good safety profile observed in previous studies. Full analysis of the data will be undertaken in the coming weeks and reviewed by external experts prior to disclosure at an upcoming international scientific congress and publication in a peer-reviewed journal later this year. First available data demonstrated a 56% reduction of dengue disease cases in a study of more than 10,000 volunteers from Asia. Initial safety data are consistent with the good safety profile observed in previous studies.