CHICAGO -- Results from an ongoing surveillance study suggest that telithromycin is active in vitro against strains of Streptococcus pneumoniae (S. pneumoniae) that are resistant to commonly prescribed classes of antibiotics. These findings, from a PROTEKT US (Prospective Resistant Organism Tracking and Epidemiology of the Ketolide Telithromycin - United States) sub-study, were presented at the 43rd annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
A total of 10,012 S. pneumoniae isolates were collected from patients with community-acquired respiratory tract infections in 242 centers across the United States. The study found that 21.2 percent of the isolates were resistant to penicillin, 27.9 percent were resistant to erythromycin, 17.1 percent were resistant to both penicillin and erythromycin and one percent was resistant to levofloxacin. Further, S. pneumoniae with multi-drug resistance to penicillin, erythromycin and levofloxacin was found in 0.4 percent of the samples. By comparison, telithromycin was active against S. pneumoniae regardless of resistance to penicillin, erythromycin and/or levofloxacin. Telithromycin was active in 99.3 percent of the 1,709 isolates both penicillin and erythromycin resistant, and in 97.6 percent of the multi-drug resistant isolates.
PROTEKT US is one of the largest surveillance studies in the United States, evaluating in its first year more than 17,000 pathogens in more than 206 sites across 44 states. The study was initiated in 2000 and was designed to monitor the spread of resistant phenotypes and genotypes of the major respiratory tract infection pathogens across the nation. It is an ongoing study that is a branch of a larger international study called PROTEKT, which altogether includes more than 500 centers in 35 countries worldwide.
Telithromycin is the first in a new class of antibiotics known as ketolides. Telithromycin was designed to deliver targeted coverage in community-acquired upper and lower respiratory tract infections. In clinical trials, the most commonly reported side effects (2 percent or more) were diarrhea, nausea and vomiting.
On Jan. 27, 2003, Aventis received an approvable letter from the U.S. Food and Drug Administration (FDA) for telithromycin tablets for the treatment of community-acquired pneumonia, acute exacerbations of chronic bronchitis and acute bacterial sinusitis. In the approvable letter, the FDA requested that Aventis provide additional analyses and information prior to marketing approval. The agency has not required additional clinical studies. Aventis is currently preparing a response to the FDA's approvable letter.