Table 1.
PD50s of ceftobiprole and other antibiotics against E. faecalis strains Βla− OG1 and Βla+ OG1 in a mouse UTI model
| Strain | Inoculum (CFU) | Antibiotic | MIC (μg/ml) | No. of doses (time [h] postinoculation) | PD50 (mg/kg body wt) |
|
|---|---|---|---|---|---|---|
| Kidney | Bladder | |||||
| Βla− OG1 | 105 | Ceftobiprolea | 1 | 1 (1) | 10 | 18 |
| Ampicillin | 1 | 2 (1, 2) | 7 | 19 | ||
| Vancomycin | 1 | 1 (1) | 31 | 36 | ||
| Βla+ OG1 | 105 | Ceftobiprole | 0.5 | 1 (1) | 7 | 15 |
| Ampicillin | 4 | 2 (1, 2) | 44 | 66 | ||
| Vancomycin | 1 | 1 (1) | 27 | 38 | ||
| Βla+ OG1 | 107 | Ceftobiprole | 1 | 1 (1) | 33 | 31 |
| Ampicillin | >128 | 2 (1, 2) | >200 | >200 | ||
| Vancomycinb | ||||||
a
Ceftobiprole (BAL 9141) was used for in vitro MIC determinations, and ceftobiprole medocaril (prodrug; BAL5788) was used for in vivo experiments.
b
Vancomycin was not tested at the higher inoculum, since it is not known to be affected by E. faecalis Bla and the purpose was to evaluate an in vivo effect of Bla on ampicillin and test the stability of ceftobiprole.