TABLE 5.

In vitro activities of NB2001 and reference antimicrobial agents against gram-negative bacteria

Organism (no. of strains)a and antimicrobial agent	MIC (μg/ml)b
	Range	50%	90%
BP M. catarrhalis (20)
NB2001	≤0.004-0.015	≤0.004	≤0.004
Ceftriaxone	≤0.015-0.5	≤0.015	0.25
Imipenem	≤0.03-0.12	≤0.03	0.06
Ciprofloxacin	0.008-0.03	0.015	0.015
Amoxicillin-clavulanate	≤1-≤1	≤1	≤1
Sulfamethoxazole	0.06-0.5	0.12	0.25
Ampicillin	≤0.12-2	0.5	2
BN M. catarrhalis (20)
NB2001	0.015-0.06	0.03	0.03
Ceftriaxone	≤0.015-≤0.015	≤0.015	≤0.015
Imipenem	≤0.03-≤0.03	≤0.03	≤0.03
Ciprofloxacin	0.008-0.03	0.015	0.015
Amoxicillin-clavulanate	≤1-≤1	≤1	≤1
Sulfamethoxazole	0.03-0.12	0.06	0.12
Ampicillin	≤0.12	≤0.12	≤0.12
BP H. influenzae (20)
NB2001	0.12-2	0.5	1
Ceftazidime	≤0.03-0.12	0.06	0.06
Ceftriaxone	≤0.015-0.03	≤0.015	≤0.015
Imipenem	0.25-0.5	0.5	0.5
Ciprofloxacin	0.004-0.015	0.008	0.015
Amoxicillin-clavulanate	≤1-4	≤1	4
Sulfamethoxazole	0.06-16	0.25	16
Ampicillin	8->32	>32	>32
BN H. influenzae (10)
NB2001	2-4	2	4
Ceftazidime	≤0.03-0.12	0.06	0.06
Ceftriaxone	≤0.015-≤0.015	≤0.015	≤0.015
Imipenem	0.06-0.5	0.25	0.5
Ciprofloxacin	0.008-0.015	0.008	0.008
Amoxicillin-clavulanate	≤1-≤1	≤1	≤1
Sulfamethoxazole	0.12-1	0.5	1
Ampicillin	≤0.12-0.25	≤0.12	0.25
E. aerogenes (30)
NB2001	0.5-16	4	8
Ceftazidime	0.12->32	32	>32
Ceftriaxone	0.03-64	16	32
Imipenem	0.25-2	1	2
Ciprofloxacin	0.008->4	0.015	1
Amoxicillin-clavulanate	32->32	32	>32
Sulfamethoxazole	0.03-32	0.12	0.5
Ampicillin	32->32	>32	>32
Gentamicin	0.25-2	0.5	1
E. cloacae (30)
NB2001	0.5->32	2	8
Ceftazidime	0.12->32	>32	>32
Ceftriaxone	0.03->64	32	>64
Imipenem	0.25-2	0.5	2
Ciprofloxacin	≤0.002->4	0.03	2
Amoxicillin-clavulanate	4->32	>32	>32
Sulfamethoxazole	0.03-32	0.06	0.5
Ampicillin	2->32	>32	>32
Gentamicin	0.25->16	0.5	4
E. coli (30)
NB2001	1-16	4	8
Ceftazidime	0.06->32	0.25	32
Ceftriaxone	≤0.015->64	0.06	8
Imipenem	0.06-0.5	0.12	0.25
Ciprofloxacin	0.004->4	0.008	>4
Amoxicillin-clavulanate	2-32	4	32
Sulfamethoxazole	≤0.015->32	0.06	>32
Ampicillin	1->32	32	>32
Gentamicin	0.25->16	0.5	2
K. pneumoniae (30)
NB2001	1->32	8	16
Ceftazidime	≤0.03->32	32	>32
Ceftriaxone	≤0.015->64	4	>64
Imipenem	0.06-1	0.12	1
Ciprofloxacin	0.008->4	0.12	>4
Amoxicillin-clavulanate	≤1->32	8	32
Sulfamethoxazole	0.06->32	0.5	>32
Ampicillin	16->32	>32	>32
Gentamicin	0.25->16	4	>16
P. aeruginosa (10)
NB2001	>32->32	>32	>32
Ceftazidime	1->32	4	>32
Ceftriaxone	2->64	64	>64
Imipenem	0.25->16	2	16
Ciprofloxacin	0.12-4	1	2
Amoxicillin-clavulanate	4->32	>32	>32
Sulfamethoxazole	>32	8	16
Ampicillin	4->32	>32	>32
Gentamicin	1->16	2	16

^aBP, β-lactamase positive; BN, β-lactamase negative; E. cloacae, Enterobacter cloacae, E. aerogenes, Enterobacter aerogenes.

^bMIC assays were performed at MRL.