European Medicines Agency (EMA) confirms positive benefit-risk balance for Multaq - European Prescribing Information Updated to Ensure Multaq Use in Appropriate Paroxysmal and Persistent AF Patients - Paris

European Medicines Agency (EMA) confirms positive

benefit-risk balance for Multaq

Prescribing Information Updated to Ensure Multaq Use

in Appropriate Paroxysmal and Persistent AF Patients -

Paris, France - September 22, 2011 - Sanofi (EURONEXT: SAN and NYSE: SNY) announced today that the Committee for Medicinal

Products for Human Use (CHMP) of the European Medicines Agency (EMA) confirmed a positive benefit-risk balance for

Multaq (dronedarone) for the treatment of a newly defined population of paroxysmal and persistent Atrial

Fibrillation (AF) patients, following its review under the Article 20 procedure.

The EMA has defined Multaq s role in the treatment of paroxysmal and persistent AF stating that the Agency s Committee for Medicinal

Products for Human Use (CHMP) has concluded that the benefits of Multaq continue to outweigh the risks for a

limited population of patients with Atrial Fibrillation.

The new indication for Multaq is: Multaq is indicated for the maintenance of sinus rhythm after successful cardioversion in adult clinically stable patients

with paroxysmal or persistent atrial fibrillation (AF). Due to its safety profile (see sections 4.3 and

4.4) Multaq should only be prescribed after alternative treatment options have been considered. Multaq should not be given to patients with left ventricular systolic dysfunction or to patients with current or previous

episodes of heart failure.

A Direct Healthcare Professional Communication (DHPC) letter informing healthcare

providers of the updates to the Multaq SPC (Summary of Product Characteristics) will be issued in the European

Union member states where Multaq (dronedarone) is currently available.

The CHMP opinion is significant as it ensures availability of an important treatment option for paroxysmal and persistent atrial fibrillation, a

growing public health concern associated with life threatening consequences, said Dr. Jean-Pierre Lehner, Chief Medical Officer, Sanofi.

Multaq is launched in 37 countries worldwide and has been

prescribed to over 440,000 patients to date.

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

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