MULTIPLE-DOSE PHARMACOKINETICS OF CEFTIBUTEN IN HEALTHY-VOLUNTEERS

The pharmacokinetics of cetibuten, a new cephalosporin antibiotic, and its conversion product, ceftibuten-trans, were studied in healthy mal e volunteers following daily oral administration of a 400-mg capsule f or 7 days. Mean concentrations of ceftibuten in plasma obtained on day 5 were similar to those obtained on day 7. Analysis of variance indic ated that the concentrations in plasma on days 5 and 7 were at steady state. The mean accumulation factor was 1.14 for day 5 and 1.13 for da y 7. The half life (2.4 h) was independent of the duration of drug adm inistration, and the mean maximum concentration of drug in plasma was 18 to 19 mu g/ml. Urinary excretion was the major elimination route fo r ceftibuten, by which 57 to 59% of the drug was excreted unchanged ov er a 24-h The amounts of ceftibuten-trans in plasma and urine were low .