Comparative antibacterial activity of a new oral cephalosporin, BMY-28100.

BMY-28100 is a new oral cephalosporin which had in vitro activity superior to that of cephalexin and cefaclor against staphylococci, beta-hemolytic streptococcal species, and Streptococcus pneumoniae. It inhibited beta-lactamase-producing Haemophilus influenzae, Neisseria gonorrhoeae, 50% of Streptococcus faecalis isolates, Listeria monocytogenes, and 50 to 75% of Escherichia coli and Klebsiella species at less than or equal to 8 micrograms/ml, but high producers of beta-lactamase were resistant. Enterobacter, Citrobacter, Morganella, Providencia, and Pseudomonas species and Bacteroides fragilis were resistant. BMY-28100 was more stable than cefaclor against hydrolysis by beta-lactamases.