Table 2.
Comparative activity of ceftolozane/tazobactam against selected European clinical Gram-negative bacilli
| MIC50 / MIC90 (mg/L) | |||||
|---|---|---|---|---|---|
| Organism | Ceftolozane/tazobactam | Ceftazidime | Cefepime | Meropenem | Piperacillin/tazobactam |
| Pseudomonas aeruginosa | 1/4 | 2/>32 | 4/>16 | 0.5/>8 | 8/>64 |
| Escherichia coli (non-ESBL) | 0.25/0.25 | 0.12/0.25 | ≤0.5/≤0.5 | ≤0.06/≤0.06 | 2/8 |
| Escherichia coli (ESBL) | 0.5/4 | 0.16/> 32 | >16/>16 | ≤0.06/≤0.06 | 8/>64 |
| Klebsiella spp. (non-ESBL) | 0.25/0.5 | 0.12/0.5 | ≤0.5/≤0.5 | ≤0.06/≤0.06 | 2/8 |
| Klebsiella spp. (ESBL) | 2/>32 | 32/>32 | ≤0.5/4 | ≤0.06/≤0.06 | 4/64 |
| Enterobacter spp. | 0.25/4 | 0.25/>32 | ≤0.5/4 | ≤0.06/≤0.06 | 4/64 |
| Proteus mirabilis | 0.5/1 | 0.06/0.25 | 0.5/≤0.5 | ≤0.06/0.12 | ≤0.5/1 |
| Citrobacter spp. | 0.25/8 | 0.25/>32 | ≤0.5/1 | ≤0.06/≤0.06 | 2/64 |
Notes: MIC breakpoint for ceftolozane/tazobactam has not been established. Data from Sader et al.39
Abbreviations: MIC, minimum inhibitory concentration; ESBL, extended-spectrum β-lactamase.