Everninomicin, a new oligosaccharide antibiotic: its antimicrobial activity, post-antibiotic effect and synergistic bactericidal activity.

Antimicrobial activity of everninomicin (SCH) 27899) in comparison with two glycopeptides (vancomycin, teicoplanin) and six beta-lactam agents was evaluated against recent clinical isolates of Gram-positive bacteria. Everninomicin showed the highest activity against the species tested and MICs90% of everninomicin against Streptococcus pneumoniae, Streptococcus pyogenes, Enterococcus faecalis, Enterococcus faecium and Clostridium difficile were 0.1, 0.1, 0.2, 0.39, 0.1 microgram/ml, respectively. MICs90% of everninomicin against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE) were 0.78 microgram/ml. Laboratory induced resistance to everninomicin in strains of S. aureus and E. faecalis occurred in a stepwise manner and at a very slow rate. Post-antibiotic effect against strains of S. aureus and E. faecalis were 1.8 and 2.6 h, respectively, and a little longer than that of vancomycin. Adherence to glass surface of an MRSA strain was strongly repressed by the addition of sub MIC of everninomicin in combination with fosfomycin.