TABLE 2

Observed versus target concentration pharmacokinetic parameters achieved in the in vitro modelc

AntibioticFree peak concn (μg/ml)Free trough concn (μg/ml)Free AUC0–24 (μg · h/ml)t1/2 (h)
TargetObservedTargetObservedTargetObservedTargetObserved
Ceftolozanea55.665.9 ± 5.711.212.3 ± 1.9679779 ± 353.73.5 ± 0.4
Amikacin63.662.5 ± 4.00.90.9 ± 0.3348358 ± 11NCNC
Colistinb0.730.72 ± 0.12NCNCNCNCNCNC
  • a Concentration and pharmacokinetic data were targeted only for the ceftolozane component of ceftolozane-tazobactam.

  • b Colistin was administered as a continuous infusion during the experiments; therefore, the free peak concentration is the mean concentration over the 24-h experiment.

  • c Data are presented as the mean ± standard deviation. AUC0–24, area under the curve for the 24-h experiment; t1/2, half-life; NC, not calculated.