Comparative Activities of TR-700 (Torezolid) against Staphylococcal Blood Isolates Collected in Spain

The in vitro activity of TR-700 (torezolid) was evaluated against a collection of 660 staphylococcal blood isolates. TR-700 showed excellent activity against all the staphylococci tested. The MIC(50) and MIC(90) values of TR-700, linezolid, daptomycin, and vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) isolates were 0.25 and 0.5, 2 and 4, 0.5 and 0.5, and 1 and 2 mu g/ml, respectively. TR-700 demonstrated greater in vitro potency than linezolid against staphylococci, including linezolid-resistant and vancomycin-nonsusceptible strains, and was 32-fold more active than linezolid against the seven cfr-positive MRSA strains tested.