In Vitro Activity of Cefepime/AAI101 and Comparators against Cefepime Non-susceptible Enterobacteriaceae
1
Center for Anti-Infective Research and Development, Hartford Hospital, 80 Seymour Street, Hartford, CT 06102, USA
2
Division of Infectious Diseases, Hartford Hospital, Hartford, CT 06102, USA
*
Author to whom correspondence should be addressed.
Academic Editor: Lawrence S. Young
Pathogens 2015, 4(3), 620-625; https://doi.org/10.3390/pathogens4030620
Received: 7 July 2015 / Revised: 30 July 2015 / Accepted: 12 August 2015 / Published: 18 August 2015
We evaluated the in vitro potency of cefepime combined with AAI101, a novel extended-spectrum β-lactamase inhibitor, against a population of clinical Escherichia coli and Klebsiella pneumoniae collected from USA hospitals. Of the 223 cefepime non-susceptible isolates, 95% were ceftazidime non-susceptible, 49% ertapenem non-susceptible, 57% piperacillin/tazobactam non-susceptible, 90% were multidrug-resistant (resistant to ≥3 drug classes), 22% produced carbapenemases, and 67% produced ESBLs. Addition of AAI101 restored the activity of cefepime such that the MIC50 was reduced from >64 mg/L for cefepime to 0.13 mg/L for cefepime/AAI101, supporting its continued development treatment for infections caused by these organisms.