title: In Vitro Activity of Ceftolozane-Tazobactam against Anaerobic Organisms Identified during the ASPECT-cIAI Study.
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.
authors.affiliation: Merck & Co., Inc., Kenilworth, New Jersey, USA eliana.armstrong@merck.com.
authors.forename: Eliana S
authors.initials: ES
authors.lastname: Armstrong
authors.affiliation: JMI Laboratories, North Liberty, Iowa, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Farrell
authors.affiliation: Merck & Co., Inc., Kenilworth, New Jersey, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Palchak
authors.affiliation: Merck & Co., Inc., Kenilworth, New Jersey, USA.
authors.forename: Judith N
authors.initials: JN
authors.lastname: Steenbergen
mesh_terms: D000693:Anaerobiosis; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001439:Bacteroides / Q000187:drug effects / Q000302:isolation & purification; D001442:Bacteroides Infections / Q000188:drug therapy* / Q000382:microbiology; D001441:Bacteroides fragilis / Q000187:drug effects / Q000302:isolation & purification; D002511:Cephalosporins / Q000627:therapeutic use*; D004359:Drug Therapy, Combination / Q000379:methods; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D059413:Intraabdominal Infections / Q000188:drug therapy* / Q000382:microbiology; D008795:Metronidazole / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000078142:Tazobactam
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; C000594038:ceftolozane, tazobactam drug combination; D008795:Metronidazole; D010397:Penicillanic Acid; D000078142:Tazobactam