Genzyme Initiates Phase 2a Clinical Trial to Evaluate Oral Therapy for Fabry Disease

Genzyme, a Sanofi company, announced today that patients have begun treatment in a Phase 2a clinical trial focused on evaluating the pharmacodynamics of GZ/SAR402671, a new oral substrate reduction therapy being investigated for the treatment of Fabry disease. The safety, tolerability and pharmacokinetics of GZ/SAR402671 will also be assessed. Genzyme plans to enroll nine treatment-naïve male adult patients with Fabry disease in this international, multicenter study.

Fabry disease is a rare lysosomal storage disorder that results in abnormal tissue deposits of a particular fatty substance (called globotriaosylceramide, also referred to as GL-3 or Gb3) throughout the body. GZ/SAR402671 is a glucosylceramide synthase inhibitor that blocks the formation of glucosylceramide (GL-1), a key intermediate in the synthesis of GL-3.

The Phase 2a trial is an open label, single-arm clinical trial. Patients will receive GZ/SAR402671 orally, once daily. The primary endpoint in the Phase 2a trial will assess the ability of GZ/SAR402671 to reduce accumulated GL-3 from the skin capillary endothelium. Upon completion of the 26 week study, patients will have the option to enroll into an extension study.

“We are excited to learn more about the potential of GZ/SAR402671, which has a different mechanism of action than the current standard of treatment for Fabry disease, enzyme replacement therapy, and a potential ability to cross the blood brain barrier,” said Genzyme’s Acting Head of Rare Diseases, Richard Peters, M.D, Ph.D. “The ongoing efforts on this program underscore our long standing commitment to develop innovative therapies intended to address the unmet needs of the Fabry patient community.”

About Fabry Disease

Fabry disease is an inherited and progressive condition that is characterized by excessive accumulation of the lipid GL-3 in various organs and tissues. Early symptoms include significant pain, gastrointestinal disturbances, as well as other manifestations, and over time, patients may experience life threatening renal, cardiac and cerebrovascular events. As a result, patients with Fabry disease typically have a shortened life span. Fabry disease affects both males and females, with approximately 10,000 diagnosed patients in the world.

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.

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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 Genzyme. Sanofi is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

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