Abstract
Background: TR-700 is the active moiety of TR-701 (DA-7157), a new oral/intravenous oxazolidinone prodrug. We examined its activity against linezolid-susceptible and -resistant staphylococci and enterococci.
Methods: MICs were determined by the CLSI agar dilution method.
Results: MICs of TR-700 were tightly clustered around 0.5 mg/L for linezolid-susceptible staphylococci and enterococci compared with 2 mg/L for linezolid. MICs for 52 linezolid-resistant isolates were raised, but only exceeded 4 mg/L for two Enterococcus faecium isolates homozygous for the G2576T 23S rRNA mutation and for one with an unknown mechanism of linezolid resistance.
Conclusions: TR-700 is 4- to 16-fold more active than linezolid and overcame most linezolid resistance in vitro.
Methods: MICs were determined by the CLSI agar dilution method.
Results: MICs of TR-700 were tightly clustered around 0.5 mg/L for linezolid-susceptible staphylococci and enterococci compared with 2 mg/L for linezolid. MICs for 52 linezolid-resistant isolates were raised, but only exceeded 4 mg/L for two Enterococcus faecium isolates homozygous for the G2576T 23S rRNA mutation and for one with an unknown mechanism of linezolid resistance.
Conclusions: TR-700 is 4- to 16-fold more active than linezolid and overcame most linezolid resistance in vitro.
| Original language | English |
|---|---|
| Pages (from-to) | 713-715 |
| Number of pages | 3 |
| Journal | Journal of Antimicrobial Chemotherapy |
| Volume | 63 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Apr 2009 |