TABLE 3.
Results of time-kill assays of 12 pneumococcal strains
| Drug and concn | No. of strains killed by time point, with Δlog10 CFU/ml (from time zero value) of:
|
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 h
|
6 h
|
12 h
|
24 h
|
|||||||||
| −1 | −2 | −3 | −1 | −2 | −3 | −1 | −2 | −3 | −1 | −2 | −3 | |
| GAR-936 | ||||||||||||
| 8× MIC | 7 | 3 | 1 | 12 | 6 | 4 | 12 | 11 | 7 | 12 | 12 | 12 |
| 4× MIC | 6 | 2 | 1 | 12 | 6 | 4 | 12 | 10 | 6 | 12 | 12 | 11 |
| 2× MIC | 5 | 2 | 1 | 11 | 5 | 3 | 12 | 9 | 6 | 12 | 11 | 11 |
| MIC | 4 | 1 | 1 | 7 | 5 | 2 | 10 | 8 | 4 | 12 | 11 | 11 |
| 0.5× MIC | 0 | 0 | 0 | 3 | 0 | 0 | 3 | 2 | 1 | 5 | 3 | 2 |
| Tetracyclinea | ||||||||||||
| 8× MIC | 3 | 1 | 0 | 5 | 3 | 3 | 5 | 4 | 3 | 6 | 6 | 5 |
| 4× MIC | 2 | 0 | 0 | 4 | 3 | 0 | 5 | 4 | 2 | 6 | 6 | 5 |
| 2× MIC | 2 | 0 | 0 | 3 | 2 | 0 | 5 | 2 | 2 | 6 | 5 | 5 |
| MIC | 1 | 0 | 0 | 2 | 0 | 0 | 3 | 2 | 0 | 3 | 3 | 1 |
| 0.5× MIC | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
| Minocyclinea | ||||||||||||
| 8× MIC | 4 | 2 | 1 | 4 | 4 | 2 | 5 | 4 | 4 | 6 | 5 | 5 |
| 4× MIC | 3 | 1 | 1 | 4 | 3 | 2 | 5 | 4 | 3 | 6 | 5 | 5 |
| 2× MIC | 2 | 1 | 0 | 4 | 2 | 2 | 5 | 4 | 3 | 6 | 5 | 4 |
| MIC | 2 | 0 | 0 | 3 | 2 | 0 | 5 | 3 | 2 | 6 | 4 | 3 |
| 0.5× MIC | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Doxycyclinea | ||||||||||||
| 8× MIC | 4 | 2 | 0 | 5 | 3 | 3 | 5 | 5 | 3 | 6 | 5 | 5 |
| 4× MIC | 3 | 1 | 0 | 5 | 3 | 0 | 5 | 5 | 3 | 6 | 5 | 5 |
| 2× MIC | 1 | 0 | 0 | 4 | 1 | 0 | 5 | 4 | 1 | 6 | 5 | 4 |
| MIC | 1 | 0 | 0 | 2 | 1 | 0 | 2 | 1 | 1 | 2 | 2 | 2 |
| 0.5× MIC | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
| Amoxicillin | ||||||||||||
| 8× MIC | 10 | 4 | 0 | 12 | 10 | 6 | 12 | 12 | 10 | 12 | 12 | 12 |
| 4× MIC | 9 | 2 | 0 | 11 | 9 | 3 | 12 | 12 | 8 | 12 | 12 | 12 |
| 2× MIC | 8 | 3 | 0 | 11 | 8 | 2 | 12 | 12 | 7 | 12 | 12 | 12 |
| MIC | 5 | 2 | 0 | 11 | 4 | 2 | 10 | 5 | 3 | 10 | 8 | 8 |
| 0.5× MIC | 1 | 0 | 0 | 2 | 1 | 0 | 1 | 1 | 0 | 2 | 1 | 1 |
| Ceftriaxone | ||||||||||||
| 8× MIC | 8 | 0 | 0 | 12 | 10 | 0 | 12 | 12 | 10 | 12 | 12 | 12 |
| 4× MIC | 8 | 1 | 0 | 12 | 9 | 1 | 12 | 11 | 8 | 12 | 12 | 12 |
| 2× MIC | 8 | 0 | 0 | 10 | 7 | 0 | 12 | 10 | 8 | 12 | 12 | 12 |
| MIC | 5 | 1 | 0 | 9 | 6 | 0 | 10 | 7 | 1 | 10 | 10 | 8 |
| 0.5× MIC | 2 | 0 | 0 | 2 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 |
| Clarithromycinb | ||||||||||||
| 8× MIC | 4 | 2 | 0 | 7 | 4 | 0 | 7 | 4 | 4 | 7 | 7 | 6 |
| 4× MIC | 3 | 1 | 0 | 6 | 3 | 0 | 7 | 4 | 4 | 7 | 6 | 6 |
| 2× MIC | 3 | 1 | 0 | 4 | 3 | 1 | 7 | 4 | 4 | 7 | 6 | 6 |
| MIC | 2 | 1 | 0 | 4 | 2 | 0 | 6 | 4 | 3 | 7 | 6 | 4 |
| 0.5× MIC | 1 | 0 | 0 | 2 | 0 | 0 | 2 | 1 | 0 | 2 | 1 | 1 |
| Imipenem | ||||||||||||
| 8× MIC | 12 | 4 | 0 | 12 | 10 | 2 | 12 | 11 | 10 | 12 | 12 | 12 |
| 4× MIC | 11 | 5 | 0 | 12 | 9 | 2 | 12 | 11 | 10 | 12 | 12 | 12 |
| 2× MIC | 11 | 3 | 0 | 12 | 9 | 4 | 12 | 11 | 10 | 12 | 12 | 12 |
| MIC | 10 | 2 | 0 | 12 | 8 | 2 | 12 | 10 | 8 | 11 | 11 | 9 |
| 0.5× MIC | 8 | 0 | 0 | 6 | 3 | 0 | 4 | 2 | 0 | 3 | 3 | 2 |
| Meropenem | ||||||||||||
| 8× MIC | 11 | 3 | 1 | 12 | 5 | 2 | 12 | 12 | 9 | 12 | 12 | 12 |
| 4× MIC | 9 | 2 | 0 | 12 | 4 | 2 | 12 | 12 | 7 | 12 | 12 | 11 |
| 2× MIC | 6 | 4 | 0 | 12 | 7 | 3 | 12 | 11 | 8 | 12 | 12 | 11 |
| MIC | 6 | 2 | 1 | 11 | 5 | 2 | 11 | 9 | 5 | 10 | 9 | 8 |
| 0.5× MIC | 1 | 0 | 0 | 2 | 0 | 0 | 1 | 0 | 0 | 2 | 1 | 1 |
| Vancomycin | ||||||||||||
| 8× MIC | 7 | 1 | 0 | 12 | 6 | 1 | 12 | 11 | 9 | 12 | 12 | 12 |
| 4× MIC | 7 | 1 | 0 | 12 | 6 | 2 | 12 | 10 | 9 | 12 | 12 | 11 |
| 2× MIC | 7 | 1 | 0 | 12 | 6 | 2 | 12 | 10 | 8 | 12 | 12 | 11 |
| MIC | 6 | 1 | 0 | 12 | 4 | 0 | 11 | 9 | 5 | 10 | 9 | 7 |
| 0.5× MIC | 0 | 0 | 0 | 2 | 0 | 0 | 2 | 0 | 0 | 2 | 2 | 0 |
a
Only strains with tetracycline MICs of <8.0 μg/ml were tested.
b
Only strains with clarithromycin MICs of <4.0 μg/ml were tested.