TABLE 3.

Amoxicillin concentrations, pharmacokinetic parameters, and T>MICs in β-lactamase-positive versus β-lactamase-negative simulations^a

Pharmacokinetic parameter	Amoxicillin				Clavulanic acid
	Total		Free		Total		Free
	β pos	β neg	β pos	β neg	β pos	β neg	β pos	β neg
Mean Concn (μg/ml) ± SD at time (h)
1	11.6 ± 0.6	11.6 ± 0.5	9.9 ± 2.2	10.4 ± 0.5	1.2 ± 0.0	1.3 ± 0.1	0.9 ± 0.1	0.9 ± 0.1
1.5	17.4 ± 0.8	17.2 ± 0.6	13.3 ± 0.9	13.6 ± 0.7	2.1 ± 0.1	2.1 ± 0.2	1.4 ± 0.2	1.5 ± 0.1
2	14.1 ± 0.5	15.5 ± 0.2	7.8 ± 0.9*	11.8 ± 0.6	1.5 ± 0.2	1.4 ± 0.2	1.0 ± 0.1	1.0 ± 0.1
3	10.5 ± 0.1	12.5 ± 0.9	2.9 ± 0.0*	10.1 ± 0.8	0.7 ± 0.1	0.7 ± 0.1	0.4 ± 0.0	0.5 ± 0.1
4	5.5 ± 0.7*	9.3 ± 0.6	0.8 ± 0.2*	8.2 ± 0.9	0.4 ± 0.0	0.4 ± 0.0	0.1 ± 0.0	0.2 ± 0.1
6	2.1 ± 0.2*	5.9 ± 0.5	<0.03	5.0 ± 0.5	0.1 ± 0.0	0.1 ± 0.0	0.1 ± 0.0	0.1 ± 0.0
8	<0.03	2.0 ± 0.3	<0.03	1.7 ± 0.3	0.1 ± 0.0	0.1 ± 0.0	<0.03	<0.03
10	<0.03	0.8 ± 0.0	<0.03	0.6 ± 0.2	<0.03	<0.03	<0.03	<0.03
12	<0.03	0.3 ± 0.1	<0.03	0.3 ± 0.1	<0.03	<0.03	<0.03	<0.03
Mean Cmax (μg/ml) ± SD	17.4 ± 0.6	17.2 ± 0.6	13.3 ± 0.9	13.6 ± 0.7	2.1 ± 0.0	2.1 ± 0.2	1.4 ± 0.1	1.5 ± 0.1
Mean AUC0-24 (μg/ml·h) ± SD	48.7 ± 0.2*	73.1 ± 1.2	22.5 ± 2.4*	60.7 ± 3.3	4.5 ± 0.0	4.7 ± 0.0	2.8 ± 0.2	2.9 ± 0.1
Mean T>MIC (% dosing interval)b	23.3	34.6	10.4	28.3

^aβ pos, β-lactamase-positive simulations; β neg, β-lactamase-negative simulations. *, P ≤ 0.012 versus β-negative simulations.

^bFor the BLPACR strain.