First large-scale phase III efficacy clinical trial for dengue vaccine completed

The first ever large-scale phase III efficacy clinical trial for a dengue fever vaccine was recently completed, finding that the three-dose vaccine led to a 56 percent reduction of dengue disease cases.

Sanofi's phase III study was conducted in Asia with more than 10,000 children between the ages of two and 14 years of age. Because there are four disease-causing serotypes of the dengue virus, however, it is not clear what subtype-specific protection is represented until a full analysis is presented.

The GAVI Alliance did not shortlist dengue vaccine for support in its most recent Vaccine Investment Strategy (2013), but the new results are considered an important step forward. GAVI said that it will continue to monitor developments and looks forward to the publication of the results, which it called encouraging, as well as to the second complementary phase III study involving more than 20,000 subjects in Latin America.

Currently the second-most prevalent vector-borne disease, dengue fever poses a threat to approximately half of the world's population. The disease is transmitted by mosquito bites, with as many as 100 million cases of dengue fever per year, 500,000 cases of dengue hemorrhagic fever and 20,000 dengue-related deaths.