Sanofi Pasteur Acquires Exclusive, Worldwide License for Acne Vaccine and Treatment- The pre-clinical vaccine was developed by r

Sanofi Pasteur Acquires Exclusive, Worldwide License for Acne Vaccine and Treatment- The pre-clinical vaccine was developed by researchers at the University of California, San Diego -

Lyon, France - September 21, 2011 - Sanofi Pasteur, the vaccines division of Sanofi (EURONEXT: SAN and NYSE: SNY), announced today a research and development collaboration with the University of California, San Diego (UC San Diego) on an immunological approach to acne prevention and treatment targeting the specific neutralization of Propionibacterium acnes factors in inflammation.

Acne vulgaris (acne) is one of the most common skin diseases worldwide and affects more than 50 million people in the United States alone.1 The disease has multiple, complex factors and is associated in particular with the Gram-positive anaerobic bacterium P. acnes that is a normal member of the human skin microflora.2 Current treatment of mild forms of acne involves killing P. acnes with bactericidal agents such as benzoyl peroxide and oral or topical antibiotics, all of which indiscriminately kill many bacterial species and disrupt the normal balance of the skin microflora.3 Long-term use of antibiotics also leads to resistant strains of P. acnes.4

"This opportunity could provide an immunotherapeutic product with significant benefits and a novel mechanism of action to address an unmet medical need," according to Elias Zerhouni, M.D., President, Global Research & Development, Sanofi. "This investigational vaccine and treatment may lead to a better solution for the many who suffer from this skin disease."

According to Sanofi Pasteur's estimates, the annual worldwide market for acne therapeutics is in excess of US $3 billion. The financial terms of the agreement were not disclosed.  The agreement includes a two-year research collaboration with Dr. Chun-Ming Huang and his associates at UC San Diego School of Medicine for further research and development.

About Acne5,6,7
Acne is an extremely common multi-factorial skin disease with a prevalence of 80 to 90 percent in adolescents. The disease sometimes continues through the teenage years; eight percent of 25 to
34-year olds and three percent of 35 to 44-year-old people continue to suffer from the disease. Moderate to severe acne occurs in 14 percent of five to 17-year olds and this group is more likely to seek treatment and currently faces an unmet medical need.  Acne is considered a chronic disease for a limited life-time period and, although often a simple and self-limited condition, it can result in psychological, physical and social implications.

About Sanofi
Sanofi, a global and diversified healthcare leader, discovers, develops and distributes therapeutic solutions focused on patients' needs. Sanofi has core strengths in the field of healthcare with seven growth platforms: diabetes solutions, human vaccines, innovative drugs, rare diseases, consumer healthcare, emerging markets and animal health. Sanofi is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

Sanofi Pasteur, the vaccines division of Sanofi, provides more than 1 billion doses of vaccine each year, 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 EUR 1 million in research and development. For more information, please visit: www.sanofipasteur.com or www.sanofipasteur.us

Forward Looking Statements
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