ACTIVITIES OF THE SEMISYNTHETIC GLYCOPEPTIDE LY191145 AGAINST VANCOMYCIN-RESISTANT ENTEROCOCCI AND OTHER GRAM-POSITIVE BACTERIA

LY191145 is the prototype of a series of compounds with activities against vancomycin-resistant enterococci derived by modification of the glycopeptide antibiotic LY264826. LY191145 had MICs for vancomycin- and teicoplanin-resistant enterococci of less than or equal to 4 mu g/ml for 50% of isolates and less than or equal to 16 mu g/ml for 90% of isolates. Its MICs for vancomycin-resistant, teicoplanin-susceptible enterococci were 1 to 8 mu g/ml. LY191145 retains the potent activities of its parent compound against staphylococci and streptococci. In vivo studies in a mouse infection model confirmed these activities. This compound indicates the potential of semisynthetic glycopeptides as agents against antibiotic-resistant gram-positive bacteria.