Tuesday, July 24, 2012

Sanofi Pasteur’s Dengue Vaccine Demonstrates Proof of Efficacy

Early data analysis confirms excellent safety profile and shows vaccine ability to protect against disease caused by three of the four dengue virus serotypes circulating in Thailand in world’s first ever efficacy study
Lyon, France - July 25, 2012 - Sanofi Pasteur, the vaccines division of Sanofi (EURONEXT: SAN and
NYSE: SNY), announced today that its tetravalent dengue vaccine candidate demonstrated proof of
efficacy against dengue, a threat to almost 3 billion people, in the world’s first ever dengue efficacy trial
conducted in Thailand, with excellent safety.
The vaccine generated antibody response for all four dengue virus serotypes. Evidence of protection was
demonstrated against three of the four virus serotypes circulating in Thailand. Analyses are ongoing to
understand the lack of protection for the fourth serotype in the particular epidemiological context of Thailand.
“Results of this first efficacy trial with Sanofi Pasteur’s dengue vaccine candidate represent a key milestone
in the quest to develop a safe and efficacious human vaccine against dengue,” said Michel De Wilde, Ph.D.,
Executive Vice President, Research & Development, Sanofi Pasteur. “This is also an important
development for global public health, since there is currently no specific treatment or prevention for
dengue. We are fully committed to making dengue a vaccine preventable disease by bringing a safe and
effective vaccine to people living in endemic regions of the world.”
Importantly, the results confirm the excellent safety profile of the vaccine candidate. The full data resulting
from this first efficacy trial are currently under review by scientific and clinical experts, as well as public
health officials. Detailed results of this study will be published in a peer-reviewed journal and presented to
the scientific community later this year.
Large scale phase III dengue vaccine clinical studies with 31,000 participants are underway in 10 countries
of Asia and Latin America. These studies will generate important additional data in a broader population
and in a variety of epidemiological settings to demonstrate vaccine efficacy against the four circulating
dengue virus serotypes.