Antibacterial activity of moxalactam (LY-127935) compared with cefotaxime and other beta-lactam antibiotics against clinical isolates of enterobacteriacea and non-fermenters.
The in vitro activity of moxalactam, a new semisynthetic 1-oxa-beta-lactam, was compared to those cefotaxime, cefuroxime, cephalothin, piperacillin and tobramycin against more than 500 clinical isolates of Enterobacteriaceae and non-fermenters. The geometric mean MIC against 450 Enterobacteriaceae in microgram/ml was 0.09 for moxalactam, 0.08 for cefotaxime, 5.3 for cefuroxime, 22.9 for cephalothin, 3.5 for piperacillin and 0.72 for tobramycin. The geometric mean MIC in microgram/ml against 60 P. aeruginosa strains was 12.7 for moxalactam, 22.9 for cefotaxime, 6.8 for piperacillin, 1.5 for tobramycin and 2.9 for cefsoludin. The minimum inhibitory and the bactericidal concentrations of moxalactam were almost the same in most species. The effect of the inoculum on the bactericidal concentration was slight, between 10(3) and 10(7) CFU/ml for the E. coli and the Klebsiella strains. In isolates of S. marcescens and P. aeruginosa the bactericidal concentrations increased by 4 to 5 log2 and in isolates of P. mirabilis the increased by 9 log2 with the largest inoculum.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002439:Cefotaxime; D002511:Cephalosporins / Q000494:pharmacology*; D002513:Cephamycins / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects*; D004756:Enterobacteriaceae Infections / Q000382:microbiology; D005285:Fermentation; D006801:Humans; D008826:Microbial Sensitivity Tests; D009070:Moxalactam; D047090:beta-Lactams / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D002513:Cephamycins; D047090:beta-Lactams; D002439:Cefotaxime; D009070:Moxalactam