Comparative in vitro activity of A-56268 (TE-031), a new macrolide antibiotic.

The in vitro activity of A-56268 (TE-031) was determined by either standard agar dilution or macrobroth tube dilution and compared with erythromycin and other antimicrobial agents against 329 clinical aerobic and anaerobic bacterial isolates. A-56268 showed good to excellent in vitro activity against methicillin-sensitive Staphylococcus aureus, Neisseria meningitidis, and most anaerobes tested with the exception of Bacteroides fragilis isolates. A-56268 had relatively poor activity against coagulase-negative staphylococci and methicillin-resistant Staphylococcus aureus. Except for Haemophilus spp., the activity of A-56268 was similar to or more potent than erythromycin against all other isolates tested. A-56268 did not have significant bactericidal activity against any of the isolates examined.