Sanofi-aventis Initiates 10,000 Patient Study With Multaq(R) in Permanent Atrial Fibrillation

New Outcomes Trial to Expand Evidence for Dronedarone in a Different AF Population.

Paris - Sanofi-aventis (EURONEXT: SAN and NYSE: SNY) announced today the initiation of a multinational, randomized, double-blind Phase IIIb trial, PALLAS, to assess the potential clinical benefit of Multaq(R) (dronedarone) in over 10,000 patients with permanent atrial fibrillation (AF) to reduce major adverse cardiovascular events. The announcement was made during Heart Rhythm 2010, the Heart Rhythm Society's 31st Annual Scientific Sessions.

To view the Multimedia News Release, please click: [http://multivu.prnewswire.com/mnr/prne/sanofiaventis/42428] Permanent AF afflicts 50% of patients suffering from AF and these patients are at high risk of major adverse cardiovascular events. The trial rationale was based on post-hoc findings from the landmark ATHENA trial, in which a trend towards reduction of CV hospitalization and death was seen in patients classified as "permanent" (i.e. with AF/AFL at each ECG recording).

"This is a trial of major significance since no anti-arrhythmic drug has ever been shown to reduce major morbidity and mortality in permanent AF patients in a large-scale clinical trial," said Stuart Connolly, MD, Division of Cardiology, McMaster University, Hamilton, Canada, one of the trial's principal investigators. "We designed the PALLAS trial to further assess the role of Multaq(R) to reduce cardiovascular outcomes in patients with AF."

The primary objective of the PALLAS trial is to demonstrate a reduction in either or both of two composite outcomes which are 1. major cardiovascular events (stroke, systemic arterial embolism, myocardial infarction or cardiovascular death) or 2. cardiovascular hospitalization or death from any cause among patients with permanent atrial fibrillation and additional risk factors. The secondary objectives are to evaluate the efficacy of Multaq(R) in preventing cardiovascular death and whether the drug is well-tolerated in this patient population.

"The initiation of the PALLAS trial confirms our strong belief in Multaq(R) and our commitment to improve AF patient well-being and overall cardiovascular health," said Marc Cluzel, MD, Executive vice-president, Research and Development, sanofi-aventis. "We are looking forward to first patient enrolment of PALLAS in the third-quarter 2010."

About PALLAS - PALLAS* is a multinational, randomized, double-blind, parallel-group, placebo-controlled, multicenter Phase IIIb trial comparing the efficacy of Multaq(R) 400mg twice-daily with placebo in permanent AF patients. All patients will receive standard treatment to control heart rate and prevent blood clots (antithrombotic therapy); patients will be randomized to receive additional treatment with either Multaq(R) 400mg BID or placebo.

Required risk factors include age above 65 years with at least one of the following major risk factors: systemic arterial embolism, myocardial infarction, documented coronary artery disease, prior stroke, symptomatic heart failure, or the combination of age above 75 years, hypertension and diabetes mellitus. Exclusion criteria include patients with New York Heart Association (NYHA) Class IV heart failure or unstable NYHA Class III heart failure.

The trial has two composite co-primary endpoints: 1. Major cardiovascular events (stroke, systemic arterial embolism, myocardial infarction or cardiovascular death). 2. Cardiovascular hospitalization or death from any cause.

There will be 10,800 patients enrolled in 43 countries at 700 sites. The trial is event-driven with a fixed Common Study End Date, meaning that the study duration will depend upon the occurrence of a statistically required number of outcome events.