– Development of next generation of High-Throughput Screening to accelerate the drug discovery process –

Paris, September 26, 2008 – Sanofi-aventis announced today the launch of the dScreen Consortium, a research initiative conducted with RainDance Technologies , Inc., Lexington, Massachusetts, and Louis Pasteur University, Strasbourg, France, to develop the next generation of High-Throughput Screening (HTS) for drug discovery applications.

The consortium was founded with the assistance of the Alsace BioValleyTM Cluster , France, which helped secure financing and support for the program.

The dScreen Consortium assembles:

– the renowned drug screening expertise of sanofi-aventis

– the unique expertise in droplet-based microreactors of the Chemical Biology Laboratory at the Institute for Science and Supramolecular Engineering ( ISIS) of Louis Pasteur University

– and RainDance Technologies’ unique capabilities to apply droplet-based microfluidic technologies to human health and disease research.

‘We are delighted to enter this partnership with two highly innovative research groups in this rapidly advancing field,’ said Martin Galvan Ph.D., Scientific Director at the sanofi-aventis research site in Strasbourg. ‘The expected gains

in terms of productivity and knowledge should significantly accelerate our drug discovery programs’.

Based in the Alsace BioValley in Strasbourg, the consortium will utilize the pico-liter volumes and ultra-high speed capabilities of RainDance’s technology and systems to achieve breakthrough performance in high-throughput drug screening methodologies.

‘This exciting project represents the first research collaboration undertaken by our new RainDance Technologies France SARL subsidiary,’ said Chris McNary, President and Chief Executive Officer of RainDance Technologies. ‘The speed, simplicity, and minute volume of our droplets eliminate the need for unnecessarily complex automation solutions in high-throughput screening. Our technology will process 10 million droplets per hour on a single benchtop instrument, dramatically accelerating the drug discovery process while conserving precious screening compounds,’ added McNary.

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‘This project is an excellent opportunity to develop the compartmentalisation of reactions in emulsion droplets for an entirely new field of application: HTS for drug discovery’ said Andrew Griffiths, head of the Chemical Biology Laboratory at ISIS. ‘University Louis Pasteur is proud to be part of this consortium which will open new scientific routes while generating top scientific lectures to our students’ said Jean-Marc Jeltsch, Vice-President, Louis Pasteur University.

‘The dScreen Consortium is a great illustration of the ‘Pôle de Compétitivité’ policy in France: the development of breakthrough innovations in drug screening through collaborative R&D programs results in strengthening local actors such as the sanofi-aventis research site and in the creation of a subsidiary of an US company in Alsace. Furthermore, the establishment of a drug screening services platform based on the results of the program will reinforce the capabilities of our cluster’ underlined Pascal Neuville, President of Alsace BioValley.

About dScreen

The aim is to develop a digital microfluidic system for quantitative HTS of bio- active compounds using purified targets and cell-based assays. The very high- throughput will enable the measurement of dose- response curves for every

compound in a chemical library. The second objective is to develop a new system for compound storage in which each compound will be stored into droplets using a microfluidic device.

About the ALSACE BIOVALLEY™ cluster

The Alsace BioValleyTM cluster’s mission is to bring together and support the development and growth of all public and private players involved in the sector of life sciences and healthcare in Alsace. The Alsace BioValleyTM cluster brings together the main organizations supporting the field of life science in Alsace, thus granting all its players a simplified, more efficient and rationalized access to the entire pool of regional resources and skills.

The Alsace BioValleyTM cluster claims to be a genuine project catalyst and to hold the position of one of the main European clusters, offering entry into the unique network of excellence provided by the trinational Biovalley cluster ( Alsace, Basel and Freiburg region).

About RainDance Technologies, Inc.

RainDance Technologies Inc. is a provider of innovative droplet-based solutions for human health and disease research. The speed and simplicity of the company’s exciting new technology enable researchers to design experiments in ways that were previously unaffordable or unimaginable.

The company’s technology produces picoliter-volume droplets at a rate of 10 million per hour. Each droplet is the functional equivalent of an individual test tube and can contain a single molecule, reaction, or cell. This versatile technology can adapt highly referenced assays for high-speed workflows with minimized process-induced bias or error.

RainDance’s initial application will focus on the targeted resequencing of the human genome – one of the fastest-growing segments of the $1 billion DNA

sequencing market. This application will enable the high-resolution analysis of genetic variation between individuals and populations at a level unmatched by current methodology.

RainDance was founded in 2004 by scientists from Harvard University; the Medical Research Centre in Cambridge, England and the ESPCI in Paris. For more information, please visit : www.raindancetechnologies.com.

About Louis Pasteur University

Louis Pasteur University (ULP, Strasbourg, France – https://www-ulp.strasbg.fr), founding partner of EUCOR (European Federation of Universities of the Upper Rhine), is a member of the League of European Research Universities (LERU, http ://www.leru.org). A strong partnership also exists with the main French research institutions (CNRS, INSERM and INRA). In the field of contract-based research with private companies, ULP has (since 1987) already set up a department for industrial relations and technology transfer (ULP-Industrie), which provides efficient support for the scientists.

About sanofi-aventis

Sanofi-aventis, a leading global pharmaceutical company, discovers, develops and distributes therapeutic solutions to improve the lives of everyone. Sanofi- aventis is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY). For more information, please visit: www.sanofi-aventis.com.

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