Ketek® (Telithromycin) highly active in vitro against Streptococcus pneumoniae

A novel investigational antibiotic has demonstrated excellent in vitro activity against isolates of Streptococcus pneumoniae (S. pneumoniae), including those resistant to penicillin, macrolide or fluoroquinolone antibiotics according to a study presented today. In vitro data from the international PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) study presented today at the 11th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), suggest that Ketek® (telithromycin) may be an effective option for the treatment of community acquired respiratory tract infections (CARTIs), particularly those caused by Streptococcus pneumoniae, the most common pathogen associated with CARTIs.

CARTIs are the most common infections treated by healthcare practitioners and represent a significant societal burden, causing 50 million deaths globally each year. As part of the worldwide PROTEKT study, bacterial isolates from patients with community-acquired pneumonia (CAP), acute bacterial exacerbation of chronic bronchitis (AECB), acute sinusitis, tonsillitis/pharyngitis or acute otitis media were collected from centres throughout the world. As of January 2001, the in vitro analysis of more than 5000 isolates collected in the PROTEKT study has confirmed the alarming spread of antimicrobial resistance among the pathogens most frequently implicated in CARTIs.

The study revealed that the overall worldwide prevalence of penicillin (PEN) resistance among pneumococci was 39.9%. Levels differed markedly among countries with South Korea recording the highest levels (80.5%). High levels of PEN resistance were also evident in Japan (65.6%), Hong Kong (58.6%), France (59.4%), Spain (43.7%) and the USA (43.6%).

The study also shows that erythromycin (ERY) resistance was highest in Asia (combined ERY resistance of 86.2%, 80.5% and 72.9% in South Korea, Japan and Hong Kong, respectively), and more than half of the isolates tested from France were resistant to erythromycin. An analysis showed that Ketek® was active against 99.8% of all S. pneumoniae isolates, including those resistant to penicillin (99.5%), macrolides (99.6%) and fluoroquinolones (100%). Ketek® was also highly active against M. catarrhalis, H. influenzae and H. parainfluenzae, including b-lactamase-producing isolates (100%, 98.3%and 83.7% susceptible, respectively). More than 95% of S. pyogenes isolates and 92.9% of mecA-isolates of S. aureus were susceptible to Ketek®.

PROTEKT data include isolates from countries spanning North America, Europe, Latin America and the Asia Pacific. PROTEKT involves 72 laboratories in 25 countries. It is an ongoing study, where researchers analyze the susceptibility of seven common and atypical community-acquired RTI-causing bacteria to most current treatments including penicillins such as amoxicillin, cephalosporins and commonly used macrolides such as azithromycin and clarithromycin as well as quinolones such as levofloxacin, moxifloxacin and gatifloxacin.

The study evaluates the in vitro activity of telithromycin. As of January 2001, more than 10,000 clinical isolates of Streptococcus pneumoniae, Streptococcus pyogenes, Moraxella catarrhalis, Haemophilus influenzae, Haemophilus parainfluenzae, Staphylococcus aureus and Legionella pneumophila have been collected from patients with RTIs such as CAP, AECB, acute otitis media and tonsillitis/pharyngitis. Unlike many previous surveillance programs, PROTEKT isolates are sent to a central laboratory and analyzed using standardized tests specifically focusing on determining microbiological activity of Ketek® and other antibiotics.

Ketolides are a novel addition to the macrolide-lincosamide-streptogramin (MLSb) group of antibiotics. Ketek® is specifically designed to offer optimal broad-spectrum coverage in both upper and lower RTIs-including those caused by resistant strains-with a short and reliable treatment regimen. Ketek® combats resistant bacteria by inhibiting the protein synthesis necessary for bacterial reproduction, binding 10 times more tightly than the macrolide erythromycin at two different sites on the bacterial ribosomes. In vitro data also suggest that Ketek® has a low propensity to induce bacterial resistance. Please note that in vitro activity does not necessarily correlate to clinical response. Ketek® is currently under review by health authorities in Europe and the U.S. for the treatment of CAP, AECB, acute sinusitis, and tonsillitis/pharyngitis.

Aventis (NYSE: AVE), a world leader in pharmaceuticals and agriculture, is dedicated to improving life through the discovery and development of innovative products. In 2000, Aventis generated group sales of € 22.3 billion and employed around 92,500 people in its Pharma and Agriculture businesses. Aventis announced in November 2000 that it intends to focus on pharmaceuticals and plans to divest its activities in agriculture. Aventis was launched in December 1999 through the merger of Hoechst AG of Germany and Rhône-Poulenc SA of France. Corporate headquarters are in Strasbourg, France. For more information, please visit: www.aventis.com.

Aventis Pharma AG is the pharmaceutical company of Aventis. Aventis Pharma is dedicated to treating and preventing human disease through the discovery, development, manufacture and sale of innovative pharmaceutical products aimed at satisfying unmet medical needs. Aventis Pharma focuses on important therapeutic areas such as cardiology, oncology, infectious diseases, arthritis, allergies and respiratory disorders, diabetes and the central nervous system disorders. Aventis Pharma has its corporate headquarters in Frankfurt, Germany. Aventis Pharma encompasses Aventis Pasteur, a world leader in vaccines based in Lyon, France, and Aventis Behring, a world leader in therapeutic proteins headquartered in King of Prussia, Pennsylvania, USA.

Statements in this news release other than historical information are forward-looking statement subject to risks and uncertainties. Actual results could differ materially depending on factors such as the availability of resources, the timing and effects of regulatory actions, the strength of competition, the outcome of litigation and the effectiveness of patent protection. Additional information regarding risks and uncertainties is set forth in the current Annual Report on Form 20-F of Aventis on file with the Securities and Exchange Commission.