Results of the Phase II SEPIA-ACS1/ TIMI-42 study presented at the plenary session of the Annual European Society of Cardiology

Sanofi-aventis (EURONEXT: SAN and NYSE: SNY) announced today that the investigational anti-Xa intravenous anticoagulant otamixaban reduced by 27 to 42 percent the odds of the composite primary endpoint of death, myocardial infarction, urgent revascularization or rescue GPIIb/IIIa use in 4 out of the 5 otamixaban tested doses, versus standard UFH/eptifibatide combination in [non-ST] ACS patients suitable for invasive strategy. The results of the SEPIA-ACS1/ TIMI-42 were presented today at the plenary session of the Annual European Society of Cardiology congress in Barcelona and simultaneously published online in The Lancet.

Otamixaban is a first in class, rapid onset antithrombotic compound, acting as a direct selective inhibitor of factor Xa. Otamixaban is originating from sanofi-aventis world-class thrombosis research portfolio and is currently in phase IIb clinical development phase.

"The data show that intermediate dosages of otamixaban may offer substantial reduction in major coronary complications in patients presenting with acute coronary syndrome, with bleeding rate comparable to current therapy," said Dr Marc Sabatine, MD, MPH, an Investigator in the TIMI Study Group and a cardiologist at Brigham and Women's Hospital, Harvard Medical School. "This research is addressing an important medical need, by potentially significantly improving outcomes of ACS patients undergoing PCI while simplifying the treatment pattern of the acute management phase of the disease," he added.

The double-blind phase II SEPIA-ACS1/ TIMI-42 study randomized 3241 patients from 36 countries in 6 treatment arms. The study assessed the efficacy and safety of five different doses of otamixaban versus the standard unfractionated heparin plus Glycoprotein IIb/IIIa inhibitor (eptifibatide), on background of standard dual antiplatelet therapy, in patients with high-risk non-ST-elevation acute coronary syndromes. SEPIA-ACS1 study showed that otamixaban displayed clinically meaningful activity on the primary endpoint from the threshold dose of 0.070 mg/kg/h, the second tested dose, with a consistent antithrombotic effect up to the 5th highest tested dosage. The lowest studied dosage was prematurely stopped due to insufficient activity, based on recommendation by an independent data monitoring board. Moreover a combined analysis of the intermediate doses (0.105 and 0.140 mg/kg/h) of otamixaban arms showed that otamixaban reduced by approximately 46 percent.

The potent antithrombotic effect of otamixaban was also accompanied with a dose-dependent bleeding profile. Combined intermediate otamixaban dosages showed a safety profile not statistically different with regard to TIMI major or minor bleeding through 7 days, in comparison to UFH and GPIIb/IIIa inhibitor comparator (RR 1.20, 95% CI 0.64-2.27,>

'The SEPIA-ACS1 trial is providing very encouraging results for a new and more effective treatment approach', said Marc Cluzel, MD Senior Vice President Research and Development sanofi-aventis. 'We aim, on the basis of these findings to address through our development program remaining patients', practionners' and payers' needs for management of ACS.'

Acute Coronary Syndromes is a general term used to regroup clinical symptoms related to acute myocardial ischemia. ACS represents an area of important medical need, as despite use of several antithrombotic therapies, death and myocardial infarction still occur in 5 to 8% of patients in the following week after an initial event.