In vitro activity of LY 333328 against anaerobic gram-positive bacteria

LY 333328 is a new semisynthetic glycopeptide with reported activity against aerobic Gram-positive cocci such as enterococci, pneumococci, streptococci and staphylococci. The present investigation was undertaken to determine the in vitro activity of LY 333328 against 178 Gram-positive anaerobic bacteria recently isolated from human infections. The activity was compared with that of vancomycin, teicoplanin, cefoxitin, imipenem, clindamycin and metronidazole. Peptostreptococci (48 strains): LY 333328, range 0.016-1.0 mg/l; vancomycin, 0.125-2.0 mg/l; teicoplanin, 0.032-2.0 mg/l; cefoxitin, 0.064-8.0 mg/l; imipenem, 0.016-0.064 mg/l; clindamycin, 0.016-1.0 mg/l; metronidazole, 0.125-8.0 mg/l. Propionibacterium acnes (31 strains): LY 333328, range 0.032-0.125 mg/l; vancomycin, 0.25-0.5 mg/l; teicoplanin, 0.25-0.5 mg/l; cefoxitin, 0.125-1.0 mg/l; imipenem, 0.032-0.064 mg/l; clindamycin, 0.016-0.064 mg/l; metronidazole, 32-> or =64 mg/l. Clostridium difficile (50 strains): LY 333328, range 0.016-2.0 mg/l; vancomycin, 0.5-4.0 mg/l; teicoplanin, 0.064-0.5 mg/l; cefoxitin, 64-128 mg/l; imipenem, 8.0 mg/l; clindamycin, 0.25-128 mg/l; metronidazole, 0.125-0.25 mg/l. Clostridium perfringens (49 strains): LY 333328, range 0.016-2.0 mg/l; vancomycin, 0.025-4.0 mg/l; teicoplanin, 0.064-4.0 mg/l; cefoxitin, 0.5-1.0 mg/l; imipenem, 0.016-0.5 mg/l; clindamycin, 0.008-1.0 mg/l; metronidazole, 1.0-4.0 mg/l. LY 333328 had an excellent in vitro activity against anaerobic Gram-positive bacteria.