Ketek® effective against respiratory tract infections with reduced susceptibility to other antibiotics

A novel investigational antibiotic is effective against respiratory tract infections caused by Streptococcus pneumoniae, including those strains that are resistant to penicillin and/or currently available macrolide antibiotics, according to a study reported today at a major scientific meeting.

The study, presented today at the 11th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) in Istanbul, Turkey, involved an analysis of data from Phase III studies of Ketek® (telithromycin) - the first in a new family of antibiotics called ketolides to be developed for clinical use. The study was designed to evaluate the effectiveness of Ketek® in patients with strains of Streptococcus pneumoniae that had reduced susceptibility to penicillin and/or erythromycin. Ketek® is currently under review by health authorities in Europe and the U.S. for the treatment of community-acquired pneumonia (CAP), acute bacterial exacerbation of chronic bronchitis (AECB), acute sinusitis and tonsillitis/pharyngitis.

Streptococcus pneumoniae infections were present in 371 patients treated with Ketek®, and in 86 patients who were treated in control arms with a comparator antibiotic. In Ketek®-treated patients, 23.9 percent (89 of 371) had strains of Streptococcus pneumoniae which showed reduced susceptibility to penicillin and/or erythromycin, while in comparator-treated patients, 15.1 percent (13 of 86) of strains were resistant according to evaluations from a central laboratory.

Patients with penicillin and/or erythromycin resistant strains of Streptococcus pneumoniae showed higher clinical cure rates than those treated with a comparator antimicrobial (85.7 percent vs. 60.0 percent respectively; PPb population). Overall clinical cure rates in patients with these resistant strains of Streptococcus pneumoniae were considerably higher in patients treated with Ketek® than in those treated with a comparator antimicrobial (91.8% vs. 70%; per-protocol population). The clinical cure rates for patients treated with Ketek® who had strains of Streptococcus pneumoniae with reduced susceptibility to penicillin and/or erythromycin, are similar to the overall clinical cure rates observed in the phase III program for patients treated with Ketek® for CAP, AECB or acute sinusitis.

In addition, post-therapy test-of-cure bacterial eradication rates were higher in the Ketek®-treated patients than in comparator treated patients (91.8% vs. 80.0% PPb population) and were consistent with the clinical cure rate. Community-acquired respiratory tract infections are among the most prevalent infectious diseases in the developed world and represent a significant socioeconomic burden. The incidence of penicillin- and/or erythromycin-resistant and multiresistant Streptococcus pneumoniae (the major respiratory pathogen) is increasing worldwide and is now a public health concern.

Ketek® is the first of a new family of antimicrobial agents called ketolides to be developed for the treatment of community-acquired respiratory tract infections. Ketolides were specifically designed to overcome antimicrobial resistance in Streptococcus pneumoniae. Ketek® has been shown in clinical trials to have significant clinical and bacteriological efficacy against a wide range of common and atypical pathogens involved in respiratory tract infections, including some drug resistant strains, and has a low potential to select for, or to induce, resistance.

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.

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