TABLE 1.

Clinically representative ELF concentrations, exposures, and pharmacokinetic/pharmacodynamic indices for meropenem and/or tobramycin in the CBR^a

Treatment	fCmax/fCmin or fCss (mg/liter)	fAUC24 (mg·h/liter)	fCmax/MIC	fT>MIC (%)	fAUC24/MIC
MER at 2 g every 8 h	25.4/0.06	115	3.18	22
MER at 6 g/day as a CI	4.79	115	0	0
MER at 6 g/day as a CI (60% ELF penetration)	9.58	230	1.20	100
TOB at 10 mg/kg every 24 h	12.3/0.11	64.4	1.54		8.05

^aMER, meropenem; TOB, tobramycin; CI, continuous infusion; fC_max, unbound maximum concentration; fC_min, unbound minimum concentration before the next dose; fC_ss, unbound average steady-state concentration; fAUC₂₄, the area under the unbound concentration-time curve over 24 h; fC_max/MIC, the ratio of the fC_max to the MIC; fT_>MIC, the cumulative percentage of a 24-h period that the unbound concentrations exceeded 1× MIC; fAUC₂₄/MIC, the ratio of the fAUC₂₄ to the MIC. The simulated half-lives were 0.8 h for meropenem and 3.5 h for tobramycin. No loading dose was administered for intermittent dosing, whereas the modified meropenem dosage regimen (6-g/day CI) was started at the fC_ss of either 4.79 mg/liter (30% ELF penetration) or 9.58 mg/liter (60% ELF penetration). The simulated ELF penetration was 30% for meropenem, unless it is specified to be 60%, and was 50% for tobramycin.