Sanofi (EURONEXT: SAN and NYSE: SNY) and its subsidiary Genzyme announced on Tuesday that the company has submitted a supplemental Biologics License Application (sBLA) to the U.S. Food and Drug Administration (FDA) and a marketing authorization application (MAA) to the European Medicines Agency (EMA) seeking approval of LEMTRADA™ (alemtuzumab) for treatment of relapsing multiple sclerosis (RMS). Genzyme is developing LEMTRADA in MS in collaboration with Bayer HealthCare.

Genzyme's clinical development program for LEMTRADA included two Phase III studies in which results for LEMTRADA were superior to Rebif® (high dose subcutaneous interferon beta-1a) on clinical and imaging endpoints, including a reduction in relapse rate. In addition, as presented last month at the American Academy of Neurology meeting, some patients with pre-existing disability treated with LEMTRADA in the CARE-MS II trial were more than twice as likely to experience a sustained reduction in disability over two years than patients treated with Rebif.

"There remains a large unmet treatment need for patients living with active disease and we believe that LEMTRADA, given its efficacy and unique dosing schedule, has the potential to transform the lives of patients with MS," said Genzyme President and CEO, David Meeker.

The regulatory submissions for LEMTRADA include two-year controlled efficacy and safety data from both treatment-naïve patients and those who relapsed while on therapy, with greater than five years of safety follow-up. Common adverse events associated with alemtuzumab were consistent across the Phase III program and included infusion-associated reactions and infections, which were generally mild to moderate in severity. Autoimmune adverse events were observed in some patients with cases being detected early through a monitoring program and managed using conventional therapies.

In addition to LEMTRADA, Genzyme's clinical development program for relapsing multiple sclerosis includes the once-daily oral treatment, AUBAGIOTM (teriflunomide), which is currently under review by the FDA and EMA.

About Alemtuzumab/LEMTRADA™

Alemtuzumab is a monoclonal antibody that selectively targets CD52, a protein abundant on T and B cells. Treatment with alemtuzumab results in the depletion of circulating T and B cells thought to be responsible for the damaging inflammatory process in MS. Alemtuzumab has minimal impact on other immune cells. The acute anti-inflammatory effect of alemtuzumab is immediately followed by the onset of a distinctive pattern of T and B cell repopulation that continues over time, rebalancing the immune system in a way that potentially reduces MS disease activity.

In both CARE-MS I and CARE-MS II trials, alemtuzumab 12 mg was given as an IV administration for a total of eight times over the course of the two-year study. The first treatment course of alemtuzumab was administered on five consecutive days, and the second course was administered on three consecutive days 12 months later. Rebif 44 mcg was administered by subcutaneous injection three times per week, each week, throughout the two years of study. In CARE-MS II, a third group of patients received alemtuzumab 24 mg (n=170), given on the same dosing schedule as the patients receiving alemtuzumab 12 mg (n=426).

Genzyme has the worldwide rights to alemtuzumab and has primary responsibility for its development and commercialization in MS. Bayer HealthCare has been co-developing alemtuzumab in MS with Genzyme. Bayer HealthCare retains an option to co-promote alemtuzumab in MS and, upon regulatory approval and commercialization, would receive contingent payments based on sales revenue.

*LemtradaTM and AubagioTM are the proprietary names submitted to health authorities for the company's investigational multiple sclerosis agent alemtuzumab and teriflunomide respectively.