In vitro susceptibility of characterized β-lactamase-producing strains tested with avibactam combinations

Henry Li; Mark Estabrook; George A Jacoby; Wright W Nichols; Raymond T Testa; Karen Bush

doi:10.1128/AAC.04191-14

In vitro susceptibility of characterized β-lactamase-producing strains tested with avibactam combinations

Antimicrob Agents Chemother. 2015 Mar;59(3):1789-93. doi: 10.1128/AAC.04191-14. Epub 2014 Dec 22.

Authors

Henry Li¹, Mark Estabrook¹, George A Jacoby², Wright W Nichols³, Raymond T Testa³, Karen Bush⁴

Affiliations

¹ Indiana University, Bloomington, Indiana, USA.
² Lahey Hospital and Medical Center, Burlington, Massachusetts, USA.
³ AstraZeneca, Waltham, Massachusetts, USA.
⁴ Indiana University, Bloomington, Indiana, USA [email protected].

Abstract

Avibactam, a broad-spectrum β-lactamase inhibitor, was tested with ceftazidime, ceftaroline, or aztreonam against 57 well-characterized Gram-negative strains producing β-lactamases from all molecular classes. Most strains were nonsusceptible to the β-lactams alone. Against AmpC-, extended-spectrum β-lactamase (ESBL)-, and KPC-producing Enterobacteriaceae or Pseudomonas aeruginosa, avibactam lowered ceftazidime, ceftaroline, or aztreonam MICs up to 2,048-fold, to ≤4 μg/ml. Aztreonam-avibactam MICs against a VIM-1 metallo-β-lactamase-producing Enterobacter cloacae and a VIM-1/KPC-3-producing Escherichia coli isolate were 0.12 and 8 μg/ml, respectively.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology*
Azabicyclo Compounds / pharmacology*
Drug Therapy, Combination / methods
Gram-Negative Bacteria / drug effects*
beta-Lactamase Inhibitors / pharmacology
beta-Lactams / antagonists & inhibitors*

Substances

Anti-Bacterial Agents
Azabicyclo Compounds
beta-Lactamase Inhibitors
beta-Lactams
avibactam