INTANZA® / IDflu®, first intradermal influenza vaccine recommended in the European Union

INTANZA® / IDflu®, first intradermal influenza vaccine recommended in the European Union

Lyon, France - December 18, 2008 -

Sanofi Pasteur, the vaccines division of sanofi-aventis Group, announced today that its seasonal influenza Intanza® / IDflu® vaccine*, the first intradermal (ID) microinjection flu vaccine, has received a positive opinion from Europe's Committee for Medicinal Products for Human Use (CHMP), the scientific committee of the European Medicines Agency (EMEA).

This CHMP positive opinion recommends approval of a marketing authorization in the EU territory for the use of Intanza® / IDflu®. This represents a first key step towards recognition of the ID route as a promising option for vaccine administration.

The vaccine was developed with the objective of improving the standard of care for the prevention of seasonal influenza infection. The submission to the EMEA in February 2008 was supported by the results of clinical trials involving more than 7,000 adult or elderly participants.

Vaccination via the ID route involves the administration of the antigen into the dermal layer of the skin. Due to the high concentration of specialized immune cells in this skin layer and their ability to effectively stimulate an immune response, ID vaccination provides direct and efficient access to the immune system.

This new, easy-to-use pre-filled microinjection system, developed in collaboration with Sanofi Pasteur's partner BD (Becton, Dickinson and Company) provides consistent and reliable1,2 intradermal influenza immunization. As the world leader in research, development and manufacturing of influenza vaccines, Sanofi Pasteur is working to develop new and improved influenza vaccines to save lives. With the production of 180 million doses of seasonal influenza vaccine in 2007, Sanofi Pasteur confirmed its leadership by supplying an estimated 40 percent of the world influenza vaccine market.

* Intanza® and IDflu® are registered trademarks of Sanofi Pasteur's novel microinjection system influenza vaccine in EU and

other countries.

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Seasonal Influenza Overview

Influenza is a disease caused by a highly infectious virus that spreads easily from person to person, primarily when an infected individual coughs or sneezes. According to the World Health Organization (WHO), 5-15% of the population is affected with upper respiratory tract infections in annual influenza epidemics. Hospitalization and deaths mainly occur in high-risk groups (elderly, people with chronic conditions/illness). Although difficult to assess, these annual epidemics are thought to result in between three and five million cases of severe illness and between 250,000 and 500,000 deaths every year around the world. Most deaths currently associated with influenza in industrialized countries occur among those over 65 years of age. The efficacy of vaccination in reducing the burden of the disease, as well as the economic burden of treating influenza, is well established.

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 1.6 billion doses of vaccine in 2007, 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:

www.sanofipasteur.com or www.sanofipasteur.us

References:

1. Laurent PE, et al Vaccine 2007; 25:8833-42. Evaluation of the clinical performance of a new intradermal vaccine

administration technique and associated delivery system

2. Laurent A, et al Vaccine 2007;25:6423-6430. Echographic measurement of skin thickness in adults by high frequency

ultrasound to assess the appropriate microneedle length for intradermal delivery of vaccines

3. http://www.who.int/vaccine_research/diseases/ari/en/print.html

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 product development, product potential 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 among other things, the uncertainties inherent in research and development, future clinical data and analysis, including post marketing, decisions by regulatory authorities, such as the FDA or the EMEA, regarding whether and when to approve any drug, device or biological application that may be filed for any such product candidates as well as their decisions regarding labelling and other matters that could affect the availability or commercial potential of such products candidates, the absence of guarantee that the products candidates if approved will be commercially successful, the future approval and commercial success of therapeutic alternatives as well as 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, 2007. Other than as required by applicable law, sanofi-aventis does not undertake any obligation to update or revise any forward-looking information or statements.

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Pascal Barollier Len Lavenda T.
+33-(0)4-37-37-50-38 T. +1-570-957-4446
pascal.barollier@sanofipasteur.com [1]
len.lavenda@sanofipasteur.com [2]
www.sanofipasteur.com www.sanofipasteur.us