Genzyme’s Once-daily, Oral AUBAGIO® (teriflunomide) Approved in Argentina for the Treatment of Relapsing Multiple Sclerosis

Genzyme, a Sanofi company (EURONEXT: SAN and NYSE: SNY), announced today Argentina’s National Administration of Drugs, Food and Medical Technology (ANMAT) has approved once-daily, oral AUBAGIO^® 14 mg as a new treatment indicated for patients with relapsing forms of multiple sclerosis (MS).

"Studied in one of the largest clinical trial programs of any MS treatment, AUBAGIO has had consistent effects across all the important measures of MS disease activity including slowing the progression of disability, reducing the number of brain lesions as detected by MRI and reducing relapses. The clinical data supporting AUBAGIO confirm its importance as a new treatment option for MS patients,” said Dr. Jorge Correale, Head of Neuroimmunology and Demyelinating Diseases, Raul Carrea Institute for Neurological Research FLENI, Argentina.

The decision by ANMAT represents the first approval for once-daily, oral AUBAGIO in Latin America. AUBAGIO is also approved in both the United States and Australia, with additional marketing applications under review by regulatory authorities around the world.

"The approval in Argentina of once-daily, oral AUBAGIO represents another important advancement for the Genzyme MS Franchise,” said Bill Sibold, SVP, Head of MS Business, Genzyme. "Genzyme is committed to becoming leaders in MS and developing differentiated treatments that can address the diverse needs of the MS community. Now approved on three continents, AUBAGIO’s established efficacy and convenient dosing can provide many patients with an attractive alternative to frequent and potentially burdensome injections.”

The ANMAT approval of AUBAGIO was based on safety and efficacy data from the TEMSO (TEriflunomide Multiple Sclerosis Oral) trial. The ongoing AUBAGIO clinical development program, involving more than 5,000 patients in 36 countries, is amongst the largest of any MS therapy. Some patients in extension trials have been treated for up to 10 years.

"AUBAGIO, in its clinical studies, has shown favorable efficacy and a well-characterized safety profile. With its once-daily oral administration and tolerability, AUBAGIO should contribute positively to the care of patients with Multiple Sclerosis,” said Dr. Edgardo Cristiano, Head of the Neurology Department of the Hospital Italiano de Buenos Aires, Argentina.

About AUBAGIO^®

AUBAGIO is an immunomodulator with anti-inflammatory properties. Although the exact mechanism of action for AUBAGIO is not fully understood, it may involve a reduction in the number of activated lymphocytes in the central nervous system (CNS).

Indications and Usage

AUBAGIO (teriflunomide) is a once-daily, oral treatment indicated for patients with relapsing forms of multiple sclerosis (MS). AUBAGIO 14 mg has shown significant efficacy across key measures of MS disease activity, including reducing relapses, slowing the progression of physical disability, and reducing the number of brain lesions as detected by MRI.

Important Safety Information About AUBAGIO

The AUBAGIO U.S. label includes a boxed warning citing the risk of hepatotoxicity and, teratogenicity (based on animal data).

In MS clinical studies with AUBAGIO, the incidence of serious adverse events were similar among AUBAGIO and placebo-treated patients. The most common adverse events associated with AUBAGIO in MS patients included increased ALT levels, alopecia, diarrhea, influenza, nausea and paresthesia.

Teriflunomide is the principal active metabolite of leflunomide, which is indicated in the U.S. for the treatment of rheumatoid arthritis. Severe liver injury including fatal liver failure has been reported in patients treated with leflunomide.

Leflunomide has greater than 2.1 million patient years of exposure in rheumatoid arthritis globally since its launch.

AUBAGIO is contraindicated in pregnant women and women of childbearing potential who are not using reliable contraception.

For full prescribing information and more information about AUBAGIO, please visit www.genzyme.com.

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.

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, consumer healthcare, emerging markets, animal health and the new Genzyme. Sanofi is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

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