Genzyme, a Sanofi company (EURONEXT:SAN and NYSE:SNY), announced today that following constructive discussions with the U.S. Food and Drug Administration (FDA) the company plans to resubmit in the second quarter its supplemental Biologics License Application (sBLA) seeking approval of Lemtrada (alemtuzumab) for the treatment of relapsing forms of multiple sclerosis. The resubmission will provide information to specifically address issues previously noted by the FDA in its December 27, 2013 Complete Response Letter. Genzyme had previously announced its intention to appeal the FDA’s Complete Response Letter. In light of the planned resubmission, the company does not expect to pursue an appeal at this time. 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 Lemtrada TM is a trademark of Genzyme Corporation. About Sanofi Sanofi, an integrated 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 (EURONEXT:SAN) and in New York (NYSE:SNY).