In Vitro Activities of a Novel Cephalosporin, CB-181963 (CAB-175), against Methicillin-Susceptible or -Resistant Staphylococcus aureus and Glycopeptide-Intermediate Susceptible Staphylococci

Abstract

ABSTRACT We examined the activity of CB-181963, a novel cephalosporin, against methicillin-resistant Staphylococcus aureus (MRSA) ( n = 200), methicillin-susceptible S. aureus (MSSA) ( n = 50), glycopeptide-intermediate Staphylococcus species (GISS) ( n = 47), and VRSA ( n = 2) isolates. CB-181963 exhibited MIC profiles similar to those of linezolid against MRSA and GISS; however, activity against MSSA was similar to that of vancomycin. Time-kill study results of investigations of activity against MRSA, MSSA, and GISS at 24 h were as follows: CB-181963 activity = vancomycin activity > linezolid activity ( P < 0.001); CB-181963 = quinupristin-dalfopristin = vancomycin > linezolid ( P < 0.05); CB-181963 > linezolid ( P = 0.003); and CB-181963 = quinupristin-dalfopristin = vancomycin. CB-181963 may provide an alternative treatment for multidrug-resistant staphylococci.