Activity of a new glycopeptide antibiotic (LY333328) against enterococci and other resistant Gram-positive organisms

A new semi-synthetic glycopeptide, LY333328, was tested for in-vitro activity against 197 strains of enterococci including strains resistant to other glycopeptides. Activity was also assessed against species with intrinsic resistance to glycopeptides. For strains of enterococci tested the LY333328 MIC(90)s were less than or equal to 0.5 mg/L. Enterococcus faecalis was less susceptible to LY333328 than other enterococci with a maximum MIC of 2.0 mg/L. Glycopeptide-resistant strains of enterococci were not more resistant to LY333328 than glycopeptide-susceptible strains but intrinsically resistant species had MICs between 4 and 8 mg/L.