Antipneumococcal and antistaphylococcal activities of ranbezolid (RBX 7644), a new oxazolidinone, compared to those of other agents

For 260 pneumococcal and 266 staphylococcal strains, ranbezolid MICs ranged from less than or equal to0.06 to 4 mug/ml. The MICs for pneumococci were similar irrespective of the strains' beta-lactam, macrolide, or quinolone susceptibilities, and ranbezolid MICs for coagulase-negative staphylococci were lower than those for Staphylococcus aureus. Ranbezolid was bacteriostatic against pneumococci. Ranbezolid MICs were similar to or lower than those of linezolid. Vancomycin and quinupristin-dalfopristin were also very active.