The World Health Organization’s Strategic Advisory Group of Experts on Immunization (SAGE) has recommended the use of Sanofi’s Dengvaxia  vaccine to prevent dengue fever in countries where the disease is endemic. National governments in countries with high dengue transmission should consider introducing the vaccine, SAGE said, as part of an integrated disease prevention strategy including vector control to effectively lower the dengue burden. This would help to achieve the WHO objectives to reduce morbidity from the fever by 25% and mortality by 50% by 2020.

The decision to recommend the French drugmaker’s vaccine follows the company’s launch of the world’s first mass vaccination program for dengue in the Philippines in early April, culminating a 20-year development process that cost €1.5 billion.

SAGE, which based its recommendations on the technical review of clinical data from 25 clinical studies conducted by Sanofi in 15 different endemic and non-endemic countries including more than 40,000 volunteers, found Dengvaxia to be 65.6% effective in the two years after vaccination among 9- to 16 year-olds.

Because of the complexity of the trial results, in which efficacy was shown to vary according to the strain and severity of the virus, the age of the patient and other factors, the experts did not recommend use of the vaccine in regions where the prevalence of the disease was less than 50%.

Produced in a dedicated facility in France, with a full-scale production capacity of 100 million vaccine doses annually, Dengvaxia is the first vaccine to be licensed for the prevention of dengue fever. Up to now, it has been approved in four countries –Mexico and Brazil and El Salvador, in addition to the Philippines. Sanofi said discussions are underway in the other approval countries to launch mass vaccination programs later this year.