Ceftibuten--in-vitro activity against respiratory pathogens, beta-lactamase stability and mechanism of action.

The in-vitro activity of ceftibuten against respiratory pathogenic bacteria was studied and compared with that of other oral beta-lactam agents. Ceftibuten displayed high activity against Haemophilus influenzae and Branhamella catarrhalis. There was reduced activity against Streptococcus pneumoniae (MIC90 16 mg/l). The protein binding of ceftibuten was 77% and the primary target site PBP 3. A high degree of stability to beta-lactamase hydrolysis was observed.