title: In vitro activity of ertapenem against common clinical isolates in relation to human pharmacokinetics.
abstract: The in vitro activity of ertapenem against bacterial pathogens isolated from patients with moderate to severe complicated intra-abdominal, complicated skin/skin structure, acute pelvic, or complicated urinary tract infection or community acquired pneumonia was compared to ceftriaxone and piperacillin-tazobactam and related to known plasma concentrations of the three agents. Ertapenem was more potent against methicillin-susceptible Staphylococcus aureus (MSSA) than ceftriaxone and piperacillin-tazobactam and was more potent and more active than both of these agents against Enterobacteriaceae and anaerobes. Piperacillin-tazobactam was the most active agent against enterococci and Pseudomonas aeruginosa. All isolates of Enterobacteriaceae (n=1088), Streptococcus pyogenes (n=37), Streptococcus agalactiae (n=48), MSSA (n=187), Haemophilus influenzae (n=59), and Moraxella catarrhalis (n=9) were susceptible to ertapenem; < 1% of 1284 anaerobes and only 1 of 113 Streptococcus pneumoniae (a penicillin-resistant isolate) were resistant to ertapenem. The MIC value at which 90% of all Enterobacteriaceae, streptococci, MSSA, H. influenzae, M. catarrhalis, and anaerobes were inhibited (MIC90) was < or = 1 microg/ml and below the mean plasma concentration of total ertapenem following a 1 g intravenous infusion for at least 24 hours, i.e., the entire recommended dosing interval, and below the free drug concentration for at least 8 h.
authors.affiliation: Merck Research Laboratories, West Point, PA, USA.
authors.forename: I
authors.initials: I
authors.lastname: Friedland
authors.forename: L A
authors.initials: LA
authors.lastname: Mixson
authors.forename: A
authors.initials: A
authors.lastname: Majumdar
authors.forename: M
authors.initials: M
authors.lastname: Motyl
authors.forename: G L
authors.initials: GL
authors.lastname: Woods
mesh_terms: D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics* / Q000494:pharmacology*; D001424:Bacterial Infections / Q000188:drug therapy; D002443:Ceftriaxone / Q000494:pharmacology; D017714:Community-Acquired Infections; D004352:Drug Resistance, Microbial; D004359:Drug Therapy, Combination / Q000494:pharmacology; D004755:Enterobacteriaceae / Q000187:drug effects; D000077727:Ertapenem; D006193:Haemophilus influenzae / Q000187:drug effects; D006801:Humans; D007769:Lactams; D008826:Microbial Sensitivity Tests; D001936:Moraxella catarrhalis / Q000187:drug effects; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D010878:Piperacillin / Q000494:pharmacology; D000077725:Piperacillin, Tazobactam Drug Combination; D013211:Staphylococcus aureus / Q000187:drug effects; D013292:Streptococcus agalactiae / Q000187:drug effects; D013297:Streptococcus pyogenes / Q000187:drug effects; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D007769:Lactams; D047090:beta-Lactams; D000077725:Piperacillin, Tazobactam Drug Combination; D002443:Ceftriaxone; D010397:Penicillanic Acid; D000077727:Ertapenem; D010878:Piperacillin