TABLE 6.
Summary of pharmacokinetics and primary and key secondary efficacy endpoints by baseline MIC cutoff values for ceftolozane/tazobactama
| Variable | Statistic | MIC ≤1 μg/mL (n = 142) |
MIC >1 μg/mL (n = 89) |
Overall (N = 231) |
|---|---|---|---|---|
| %ƒT>CT >1 μg/mL for tazobactam | Mean (SD) | 72.6 (24.8) | 83.9 (22.1) | 77.0 (24.4) |
| Median (min–max) | 74.7 (22.8–99.0) | 99.0 (36.3–99.0) | 89.2 (22.8–99.0) | |
| %ƒT>MIC for ceftolozane | Mean (SD) | 98.9 (1.1) | 67.3 (41.7) | 86.7 (30.1) |
| Median (min–max) | 99.0 (86.1–99.0) | 99.0 (0.0–99.0) | 99.0 (0.0–99.0) | |
| Ceftolozane/tazobactam MIC, μg/mL | Mean (SD) | 0.5 (0.3) | 54.1 (83.9) | 21.1 (58.1) |
| Median (min–max) | 0.5 (0.1–1.0) | 8.0 (2.0–256.0) | 1.0 (0.1–256.0) | |
| 28-day all-cause mortality,b n (%) | Death | 19 (13.4) | 17 (19.1) | 36 (15.6) |
| Clinical cure at TOC visit,c n (%) | Cure | 102 (71.8) | 49 (55.1) | 151 (65.4) |
%fT>CT >1 μg/mL, percentage of time the concentration of free tazobactam in plasma exceeded the threshold concentration of 1 μg/mL; %fT>MIC, percentage of time the concentration of free ceftolozane in plasma exceeded the MIC; EOT, end of treatment; max, maximum; min, minimum; TOC, test of cure.
Mortality was assessed on days 14 and 28; the 28-day all-cause mortality endpoint accounted for deaths on or before day 28.
Clinical response assessments were performed at the EOT, TOC, and late follow-up visits. Determination of clinical response was based on an overall assessment of clinical status based on signs, symptoms, and available laboratory data. Clinical responses at EOT and TOC visits were classified as cure, failure, or indeterminate. “Clinical cure” was a favorable clinical response.