Sanofi Pasteur Presents Positive Results of Tetravalent Dengue Candidate Vaccine

Sanofi Pasteur Presents Positive Results of Tetravalent Dengue Candidate Vaccine

November 06, 2007

    PARIS, Nov. 6 /Xinhua-PRNewswire/ -- Sanofi Pasteur,
the vaccines division of sanofi-aventis Group, announced
today positive results in the development of a vaccine for
the global prevention of dengue fever, one of the most
widespread tropical diseases. The results are being
presented today at the American Society of Tropical
Medicine and Hygiene (ASTMH)'s 56th annual meeting held in
Philadelphia, Pennsylvania, USA.

    These results have prompted Sanofi Pasteur to
immediately expand ongoing clinical trials in Asia and
Latin America. Submission to health authorities for
registration is anticipated in 2012.

    "Sanofi Pasteur made research for a vaccine
against dengue fever one of its top priorities by investing
in the most promising technology and dedicating top
scientists to this lifesaving project," said Wayne
Pisano, President and Chief Executive Officer of Sanofi
Pasteur. "Sanofi Pasteur's goal is to make dengue
fever a vaccine-preventable disease as quickly as possible
with a vaccine available to people living in endemic
countries or traveling to tropical destinations."

    Immunization with Sanofi Pasteur's tetravalent dengue
candidate vaccine generated a sero-neutralizing antibody
response against all four serotypes of the virus
responsible for dengue fever in 100 percent of adults who
participated in a trial in the United States.(1)

    "Developing a dengue vaccine has been a major
challenge for over a decade, and we are very pleased with
the breakthrough progress made by Sanofi Pasteur with its
tetravalent dengue vaccine," said Harold Margolis, MD,
Director of the Pediatric Dengue Vaccine Initiative (PDVI).
"We believe this moves the world closer to a dengue
vaccine that will be available for people who most need
it."

    Dengue fever is a mosquito-borne disease affecting up
to 100 million people each year and resulting in 24,000
deaths, mostly among children, according to estimates from
the World Health Organization (WHO).(2),(3) Overall, the
disease is a potential threat for close to half the world's
population. Dengue disease if often cyclical and causes
spikes in demand on local medical resources and places
tremendous pressure on strained hospitals and clinics
located in endemic countries.

    Dengue fever occurs mostly in tropical and subtropical
countries and it is spreading to new parts of the globe
each year. For example, outbreaks recently have been
observed in Paraguay and the Middle East. In addition,
dengue affects countries such as Australia (Queensland) and
the United States (Puerto Rico, Texas-Mexico border, Hawaii
and the US-affiliated Pacific Islands). A substantial
number of people traveling to endemic regions are also
infected each year.

    Sanofi Pasteur's tetravalent dengue candidate vaccine
is based on a new technology incorporating the protein
envelopes that provide immunity against the four virus
types responsible for dengue fever and the most severe
forms of the disease-dengue hemorrhagic fever and dengue
shock syndrome.

    About Sanofi-aventis

    Sanofi-aventis, a leading global pharmaceutical
company, discovers, develops and distributes therapeutic
solutions to improve the lives of everyone. Sanofi-aventis
is listed in Paris (EURONEXT: SAN) and in New York (NYSE:
SNY).

    Sanofi Pasteur, the vaccines division of sanofi-aventis
Group, provided more than a billion doses of vaccine in
2006, making it possible to immunize more than 500 million
people across the globe. A world leader in the vaccine
industry, Sanofi Pasteur offers the broadest range of
vaccines protecting against 20 infectious diseases. The
company's heritage, to create vaccines that protect life,
dates back more than a century. Sanofi Pasteur is the
largest company entirely dedicated to vaccines. Every day,
the company invests more than EUR1 million in research and
development. For more information, please visit:
http://www.sanofipasteur.com or
http://www.sanofipasteur.us.

    Forward Looking Statements

    This press release contains forward-looking statements
as defined in the Private Securities Litigation Reform Act
of 1995, as amended. Forward-looking statements are
statements that are not historical facts. These statements
include financial projections and estimates and their
underlying assumptions, statements regarding plans,
objectives, intentions and expectations with respect to
future events, operations, products and services, and
statements regarding future performance. Forward-looking
statements are generally identified by the words
"expects," "anticipates,"
"believes," "intends,"
"estimates," "plans" and similar
expressions. Although sanofi-aventis' management believes
that the expectations reflected in such forward-looking
statements are reasonable, investors are cautioned that
forward-looking information and statements are subject to
various risks and uncertainties, many of which are
difficult to predict and generally beyond the control of
sanofi-aventis, that could cause actual results and
developments to differ materially from those expressed in,
or implied or projected by, the forward-looking information
and statements. These risks and uncertainties include those
discussed or identified in the public filings with the SEC
and the AMF made by sanofi-aventis, including those listed
under "Risk Factors" and "Cautionary
Statement Regarding Forward-Looking Statements" in
sanofi-aventis' annual report on Form 20-F for the year
ended December 31, 2006. Other than as required by
applicable law, sanofi-aventis does not undertake any
obligation to update or revise any forward-looking
information or statements.

    (1) Data analyzed by the WHO Flavivirus Laboratory
Reference Center, 
        Mahidol University, Bangkok, Thailand
    (2) State of the art of vaccine research and
development. WHO/IVB/06.01
    (3) World Health Organization, What is dengue? What is
dengue 
        haemorrhagic fever? Available at: 
       
http://whqlibdoc.who.int/hq/2001/WHO_CDS_CPE_SMT_2001.9.pdf


    For more information, please contact:

    Sanofi Pasteur
    Pascal Barollier
    Media Relations
    Tel: [phone]
    [e-mail]

    Sanofi Pasteur
    Len Lavenda
    Media Relations US
    Tel: [phone]
    [e-mail]