Sanofi Pasteur, the vaccines division of Sanofi, Monday announced the publication of the detailed results of the final landmark phase III clinical efficacy study in Latin America in The New England Journal of Medicine.

Aedes aegypti/CDC
Aedes aegypti/CDC

Overall efficacy against any symptomatic dengue disease was 60.8 percent in children and adolescents 9-16 years old who received three doses of the vaccine. Analyses show a 95.5 percent protection against severe dengue and an 80.3 percent reduction in the risk of hospitalization during the study. The results of this second phase III efficacy study confirm the high efficacy against severe dengue and the reduction in hospitalization observed during the 25-month active surveillance period of the first phase III efficacy study conducted in Asia, highlighting the consistency of the results across the world.

Safety analyses (solicited reactions, unsolicited events and Serious Adverse Events SAEs) during the study showed similar reporting rates between the vaccine and control groups and are consistent with the favorable safety profile observed during the 25-month active surveillance period of the previous efficacy study conducted in Asia. The full data of the Latin American study are also presented at the American Society of Tropical Medicine and Hygiene (ASTMH) Annual Meeting, 2-6 November 2014.

Sanofi Pasteur’s phase III efficacy clinical study program for its dengue vaccine candidate was conducted in over 31,000 participants across 10 endemic countries in Asia2 and Latin America. Sanofi Pasteur will file for registration of its vaccine candidate and, subject to regulatory approval, the world’s first dengue vaccine could be available in the second half of 2015.

“We plan to submit the vaccine for licensure in 2015 in endemic countries where dengue is a public health priority,” said Olivier Charmeil, President and CEO of Sanofi Pasteur. “We are committed to supporting countries’ ambitions to significantly impact the human and economic burden of dengue through comprehensive vaccination programs. Our goal is to help meet the WHO’s objectives to reduce dengue mortality by 50% and morbidity by 25% by 2020.”

Dengue is a threat to over 2.5 billion people, nearly half the world’s population, and is a pressing public health priority in over 100 countries in the Americas and in Asia. Every year, an estimated 500,000 people, including children, are hospitalized due to severe dengue, which puts a huge strain on health care systems particularly during outbreaks. Dengue has dramatically increased over the past 30 years with an acceleration over the last decade due to travel and urbanization.

“Healthcare systems can be paralyzed when trying to cope with a dengue outbreak. The economic and societal costs can be staggering,” said Dr Roberto Tapia-Conyer, Director General Carlos Slim Foundation, Mexico. “Broad public immunization programs will be critical in achieving the full benefit of a dengue vaccine within a public health perspective, to reach the
control of the disease.”

“Until now, we were only able to provide supportive care for patients with dengue. On the strength of the outcome of this phase III efficacy study, we hope this will become an effective preventive measure against dengue,” said Dr. Rivaldo Cunha, MD, Infectious Disease Specialist, Associate Professor, Faculty of Medicine Universidade de Mato Grosso do Sul, Brazil, and a principal investigator in the study. “I will welcome a dengue vaccine that can prevent the personal suffering of severe disease and hospitalization.”

Sanofi Pasteur is already producing the vaccine in a newly dedicated production facility in Neuville-sur-Saône, France, which will be capable of providing timely supply of large quantities of vaccines to meet the global public health demand.