In vitro activity of BMY-28142 in comparison with those of other beta-lactam antimicrobial agents

The in vitro susceptibility of 406 clinical isolates to BMY-28142, a new semisynthetic cephem, was evaluated and compared with cefpimizole, HR 810, ceftazidime, cefotaxime, moxalactam, and cefoperazone in a broth microdilution assay. On a weight basis, the activity of BMY-28142 against Escherichia coli, Proteus species, and Klebsiella-Enterobacter-Serratia was superior to the other cephems. Against gentamicin-susceptible and -resistant Pseudomonas aeruginosa, BMY-28142 was more active than the other cephems, except ceftazidime and HR 810. A total of 74% of gram-negative and 56% of gram-positive isolates resistant to third-generation cephalosporins were susceptible to less than or equal to 8 micrograms of BMY-28142 per ml. Finally, for 83% of tested isolates, the bactericidal concentration of BMY-28142 was within one dilution of the inhibitory concentration.