Comparative in vitro activity of telithromycin (HMR 3647), three macrolides, amoxycillin, cefdinir and levofloxacin against gram-positive clinical isolates in Japan.

The in vitro activities (MIC and MBC) of telithromycin (HMR 3647) against clinical isolates in Japan were investigated in comparison with those of erythromycin A, clarithromycin, azithromycin, amoxycillin, cefdinir and levofloxacin. Telithromycin was more potent than the reference compounds against erythromycin A-susceptible or resistant Streptococcus pneumoniae isolates possessing either mef (mefA or mefE) genes or the ermB gene. Against erythromycin A-susceptible or inducibly resistant Staphylococcus aureus and erythromycin A-susceptible and intermediate Enterococcus faecalis, telithromycin was highly active.