In Vitro Activity of Ceftolozane-Tazobactam against Anaerobic Organisms Identified during the ASPECT-cIAI Study

Antimicrob Agents Chemother. 2015 Nov 9;60(1):666-8. doi: 10.1128/AAC.01964-15. Print 2016 Jan.

Abstract

The in vitro activities of ceftolozane-tazobactam, meropenem, and metronidazole were determined against anaerobic organisms isolated from patients with complicated intraabdominal infections (cIAI) in global phase III studies. Ceftolozane-tazobactam activity was highly variable among different species of the Bacteroides fragilis group, with MIC90 values ranging from 2 to 64 μg/ml. More-potent in vitro activity was observed against selected Gram-positive anaerobic organisms; however, small numbers of isolates were available, and, therefore, the clinical significance of these results is unknown. Variable activity of ceftolozane-tazobactam against anaerobic organisms necessitates use in combination with metronidazole for the treatment of cIAI.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Anti-Bacterial Agents / therapeutic use*
  • Bacteroides / drug effects
  • Bacteroides / isolation & purification
  • Bacteroides Infections / drug therapy*
  • Bacteroides Infections / microbiology
  • Bacteroides fragilis / drug effects
  • Bacteroides fragilis / isolation & purification
  • Cephalosporins / therapeutic use*
  • Drug Therapy, Combination / methods
  • Gram-Positive Bacteria / drug effects
  • Gram-Positive Bacteria / isolation & purification
  • Gram-Positive Bacterial Infections / drug therapy*
  • Gram-Positive Bacterial Infections / microbiology
  • Humans
  • Intraabdominal Infections / drug therapy*
  • Intraabdominal Infections / microbiology
  • Metronidazole / therapeutic use*
  • Microbial Sensitivity Tests
  • Penicillanic Acid / analogs & derivatives*
  • Penicillanic Acid / therapeutic use
  • Tazobactam

Substances

  • Anti-Bacterial Agents
  • Cephalosporins
  • ceftolozane, tazobactam drug combination
  • Metronidazole
  • Penicillanic Acid
  • Tazobactam

Grants and funding

This study was funded by Merck & Co., Inc., Kenilworth, NJ, USA.