TABLE 2.
In vitro MIC results for telavancin when tested against Gram-positive isolates using previously established broth microdilution method and revised reference method
| Organism (na) | Methodb | MIC (μg/ml) |
MIC50/MIC90 ratioc | |||
|---|---|---|---|---|---|---|
| Range | Mode | 50% | 90% | |||
| All (462) | Previous | ≤0.004–>8 | 0.25 | 0.25 | 2 | 4/8 |
| Revised | ≤0.004–8 | 0.03 | 0.06 | 0.25 | ||
| S. aureus (100) | Previous | 0.06–0.5 | 0.25 | 0.25 | 0.5 | 8/8 |
| Revised | 0.015–0.25 | 0.03 | 0.03 | 0.06 | ||
| CoNS (101)d | Previous | 0.06–0.5 | 0.25 | 0.25 | 0.5 | 4/8 |
| Revised | 0.015–0.12 | 0.06 | 0.06 | 0.06 | ||
| E. faecalis (61)e | Previous | 0.12–>8 | 0.5 | 0.5 | 8 | 4/2 |
| Revised | 0.03–8 | 0.12 | 0.12 | 4 | ||
| E. faecalis VanSf (41) | Previous | 0.12–1 | 0.5 | 0.5 | 1 | 4/8 |
| Revised | 0.03–0.25 | 0.12 | 0.12 | 0.12 | ||
| E. faecium (44)g | Previous | 0.06–4 | 0.12, 4h | 0.25 | 4 | 8/2 |
| Revised | 0.015–4 | 0.03 | 0.03 | 2 | ||
| E. faecium VanSf (21) | Previous | 0.06–0.5 | 0.12 | 0.12 | 0.25 | 4/8 |
| Revised | 0.015–0.06 | 0.03 | 0.03 | 0.03 | ||
| S. pneumoniae (50) | Previous | ≤0.004–0.12 | 0.03 | 0.03 | 0.06 | 4/2 |
| Revised | ≤0.004–0.06 | 0.008 | 0.008 | 0.03 | ||
| BHS (25)i | Previous | 0.03–0.12 | 0.06 | 0.06 | 0.12 | 2/4 |
| Revised | 0.015–0.06 | 0.03 | 0.03 | 0.03 | ||
| VGS (25)j | Previous | 0.03–0.12 | 0.06 | 0.06 | 0.12 | 2/4 |
| Revised | 0.015–0.06 | 0.03 | 0.03 | 0.03 | ||
| Challenge (56)k | Previous | 0.06–8 | 0.25, 0.5h | 0.5 | 4 | 8/1 |
| Revised | 0.015–8 | 0.06 | 0.06 | 4 | ||
n, no. of isolates tested.
Previously established BMD panels prepared with DMSO and water as the solvent and diluent, respectively, and no P-80 supplementation versus a revised BMD panel (DMSO as solvent and diluent and P-80 supplementation [0.002%]).
MIC50 obtained by the previous method/MIC50 obtained by the revised method; and MIC90 obtained by the previous method/MIC90 obtained by the revised method.
CoNS, coagulase-negative staphylococci.
Includes 20 VRE (15 VanA and 5 VanB phenotypes).
VanS, vancomycin susceptible.
Includes 23 VRE (17 VanA and 6 VanB phenotypes).
Bimodal MIC distribution (two modal values).
BHS, beta-hemolytic streptococci.
VGS, viridans group streptococci.
Represent strains with key resistance phenotypes (11 hVISA, 5 VISA, 6 VRSA, 10 VRE, 13 daptomycin-nonsusceptible staphylococci, and 11 linezolid-resistant staphylococci).