Press Releases (2005)

Study Demonstrates that Benzaclin® Topical Gel (clindamycin 1%-benzoyl peroxide 5% gel) Provided a Numerically Greater Reduction in Acne Lesions than Tretinoin 0.025% Gel Plus Clindamycin 1% Gel

Results of study presented at the 24th Annual Fall Clinical Dermatology Conference in Las Vegas

Berwyn, PA — October 27, 2005 — Dermik Laboratories, the North American dermatology arm of the sanofi-aventis Group (NYSE: SNY), announced at the 24th Annual Fall Clinical Dermatology Conference the results of a study examining efficacy and safety of three anti-acne treatment regimens. The study showed that patients using BenzaClin® alone had a numerically greater reduction in acne lesions when compared to patients using a combination of tretinoin 0.025% gel plus clindamycin 1% gel.

The 10-week evaluator-blind, multi-center trial randomized 132 patients to three treatment groups to examine the change from baseline in the number of inflammatory and non-inflammatory lesions at each visit. The treatment groups were Group 1 (BenzaClin®), Group 2 (tretinoin 0.025% gel plus clindamycin 1% gel) and Group 3 (BenzaClin® plus tretinoin 0.025% gel plus clindamycin 1% gel).

By the second week of the study, patients who received BenzaClin® alone (Group 1) had statistically significant improvement in the reduction of inflammatory lesions compared with patients in both Group 2 and Group 3, demonstrating its rapid onset of action.

"Researchers have long hypothesized that using more than one medication in treating acne may provide a clinical benefit over one medication alone," said study investigator, Steven Bowman, Medical Director, Tampa Bay Medical Research, Inc. in Clearwater, Florida. "This study shows that it is not necessary to add multiple treatments to a combination therapy, and that BenzaClin® is an effective treatment option when used alone."

At study conclusion, patients who had BenzaClin® in their treatment, Group 1 and Group 3, had a significantly greater reduction in inflammatory lesions than patients using a combination of tretinoin 0.025% gel plus clindamycin 1% gel, Group 2. In addition, the difference in total lesion reduction between Group 1 and Group 3 was not statistically significant.

Adverse events reported in this study were consistent with those typically seen with the use of topical anti-acne combination therapies; however, more adverse events were reported in the patients who received all three medications (Group 3). Additionally, patients who used BenzaClin® alone (Group 1) experienced numerically less application site dryness, a common side effect of topical acne medications.

About Acne
Although the exact cause of acne is unknown, it is one of the most common skin diseases affecting nearly 85 percent of people between the ages of 12 and 24. While acne commonly begins in puberty, the disease is not restricted to any age group. Adults in their 20s, 30s, 40s – even into their 50s – can get acne. Acne usually begins with hormonal changes as teenagers start to mature. It occurs when the sebaceous follicles, which are generally found on the face and trunk of the body, are clogged with excessive amounts of sebum (oil) and dead skin cells. The mixture of oil and cells allows bacteria that normally live on the skin to grow in the plugged follicles. These bacteria produce chemicals and enzymes and attract white blood cells that cause inflammation. The follicle blockage may cause the formation of non-inflammatory lesions (whiteheads and blackheads) or inflammatory lesions (pimples).

About BenzaClin®
BenzaClin® is proven to be effective in treating many kinds of acne, including whiteheads, blackheads, and pimples. In clinical trials, BenzaClin® worked better than either clindamycin or benzoyl peroxide alone for the topical treatment of acne. With BenzaClin®, improvements have been shown to occur in as early as two weeks. BenzaClin® is an acne product you can get with a doctor's prescription. Side effects are usually limited to the skin and include dry skin, itching, peeling, redness and sunburn. Also, clindamycin, an ingredient in BenzaClin®, may cause diarrhea. If you experience severe diarrhea, stop using BenzaClin® and call your doctor immediately. You should not use BenzaClin® if you are allergic to clindamycin, benzoyl peroxide, or the antibiotic lincomycin, or if you have a history of colitis.

For more information on this treatment, please call 1-877-338-ACNE or log on to www.BenzaClin.com.

About Dermik Laboratories
Dermik Laboratories conducts the North American dermatology business of sanofi-aventis. Dermik Laboratories has nearly 60 years of experience in the development, marketing and distribution of innovative prescription pharmaceutical products. In 2004, Dermik created a new division, Dermik Aesthetics, that focuses on marketing innovative, enduring, and reliable treatments to improve appearance and well-being. Dermik's mission is to foster healthy-looking skin and in turn, a healthy outlook for life.

About sanofi-aventis
The sanofi-aventis Group is the world's third largest pharmaceutical company, ranking number one in Europe. Backed by a world-class R&D organization, sanofi-aventis is developing leading positions in seven major therapeutic areas: cardiovascular, thrombosis, oncology, metabolic diseases, central nervous system, internal medicine, and vaccines. The sanofi-aventis Group is listed in Paris (EURONEXT: SAN) and in New York (NYSE: SNY)

Forward Looking Statements
This press release contains forward-looking statements as defined in the Private Securities Litigation Reform Act of 1995. Forward-looking statements are statements that are not historical facts. These statements include financial projections and estimates and their underlying assumptions, statements regarding plans, objectives and expectations with respect to future operations, products and services, and statements regarding future performance. Forward-looking statements are generally identified by the words "expect," "anticipates," "believes," "intends," "estimates," "plans" and similar expressions. Although sanofi-aventis' management believes that the expectations reflected in such forward-looking statements are reasonable, investors are cautioned that forward-looking information and statements are subject to various risks and uncertainties, many of which are difficult to predict and generally beyond the control of sanofi-aventis, that could cause actual results and developments to differ materially from those expressed in, or implied or projected by, the forward-looking information and statements. These risks and uncertainties include those discussed or identified in the public filings with the SEC and the AMF made by sanofi-aventis, including those listed under "Risk Factors" and "Cautionary Statement Regarding Forward-Looking Statements" in sanofi-aventis' annual report on Form 20-F for the year ended December 31, 2004. Other than as required by applicable law, sanofi-aventis does not undertake any obligation to update or revise any forward-looking information or statements.

Sanofi-aventis Group subsidiaries in the United States include Sanofi-Synthelabo Inc., Aventis Pharmaceuticals Inc. and Sanofi Pasteur Inc.