The in vitro activity of tigemonam: a comparison with other antimicrobial agents

The activity of tigemonam was compared with that of aztreonam, cefuroxime, cephalexin, amoxicillin/clavulanate potassium, gentamicin, and ofloxacin, using an agar dilution method. Tigemonam was active against strains containing known beta-lactamases of Tem and Oxa types, but strains containing broad-spectrum (group IV) enzymes were less susceptible. The MIC90 of tigemonam against the common Enterobacteriaceae was less than or equal to 0.25 mg/L. The MIC90S against Haemophilus influenzae and Neisseria gonorrhoeae were 0.5 and 0.06 mg/L, respectively. Pseudomonas, staphylococci, and Bacteroides sp. were less susceptible (MIC90 greater than 128 mg/L). Protein binding in human serum was found to be 62.5%; the presence of serum had only a modest effect on the activity of tigemonam.