Agency Action Expected in Q4 2014

CAMBRIDGE, MA, USA I May 30, 2014 I Genzyme, a Sanofi company (EURONEXT: SAN and NYSE: SNY), announced today that the U.S. Food and Drug Administration (FDA) has accepted for review the company’s resubmission of its supplemental Biologics License Application (sBLA) seeking approval of LemtradaTM (alemtuzumab) for the treatment of relapsing forms of multiple sclerosis. A six-month review period has been assigned for the Lemtrada sBLA. Genzyme expects FDA action on the sBLA in the fourth quarter.

This resubmission is based on data from the same clinical studies included in the original sBLA, and provides supplemental analyses and additional information to specifically address issues previously noted by the FDA in its December 27, 2013 Complete Response Letter. The company resubmitted the sBLA earlier this month following constructive discussions with the agency.

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.

Genzyme holds the worldwide rights to alemtuzumab and has primary responsibility for its development and commercialization in multiple sclerosis. Bayer HealthCare holds the right to co-promote alemtuzumab in MS in the United States. Upon commercialization, Bayer will receive contingent payments based on global sales revenue.

Genzyme® is a registered trademark and LemtradaTM is a trademark of Genzyme Corporation.

About Sanofi

Sanofi, a global 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 (SAN.PA) and in New York (SNY).

SOURCE: Genzyme