Genzyme Announces European Approval of Framingham Manufacturing Plant Paris, France

Genzyme Announces European Approval of

Framingham Manufacturing Plant

Paris, France - January 18, 2012 - Sanofi (EURONEXT: SAN and NYSE: SNY) and its subsidiary Genzyme announced today that the European Medicines Agency (EMA) has approved its manufacturing plant in

Framingham, Mass., for the production of Fabrazyme (agalsidase beta).

This approval by the EMA represents an important milestone in our manufacturing recovery and path toward unconstrained

supply for all patients, said Genzyme s President and CEO David Meeker. Providing the Fabry community with consistent access to treatment, increasing our inventory of Fabrazyme and working toward all regulatory approvals of our Framingham plant are our highest priorities, and we remain on

track to achieve all of these crucial goals.

The complete return to normal supply levels of Fabrazyme globally will not be immediate, as it will take time to obtain all global regulatory approvals throughout the year

and due to production lead times.

About Genzyme, a Sanofi Company

Genzyme has pioneered the development and delivery of transformative therapies for patients affected by rare and debilitating diseases for over 30 years. We accomplish our goals through world-class

research and with the compassion and commitment of our employees. With a focus on rare diseases and multiple sclerosis, we are dedicated to making a positive impact on the lives of the patients and families we serve. That goal guides and inspires us

every day. Genzyme s portfolio of transformative therapies, which are marketed in countries around the world, represents groundbreaking and life-saving advances in medicine. As a Sanofi company, Genzyme benefits from the reach and resources of

one of the world s largest pharmaceutical companies, with a shared commitment to improving the lives of patients. Learn more at www.genzyme.com.

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).

Forward Looking Statements

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plans and similar expressions. Although Sanofi s 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, 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 EMA, 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 labeling 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,

the Group s ability to benefit from external growth opportunities as well as those discussed or identified in the public filings with the SEC and the AMF made by Sanofi, including those listed under Risk Factors and Cautionary

Statement Regarding Forward-Looking Statements in Sanofi s annual report on Form 20-F for the year ended December 31, 2010. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any

forward-looking information or statements.