Cefepime. A review of its antibacterial activity, pharmacokinetic properties and therapeutic use.

Cefepime is a 'fourth' generation cephalosporin that has a broader spectrum of antibacterial activity than the third generation cephalosporins and is more active in vitro against Gram-positive aerobic bacteria. The fact that cefepime is stable to hydrolysis by many of the common plasmid- and chromosomally-mediated beta-lactamases, and that it is a poor inducer of type I beta-lactamases, indicates that cefepime may be useful for treatment of infections resistant to earlier cephalosporins. In comparative trials, cefepime 1 to 2 g, usually administered intravenously twice daily, was as effective as ceftazidime 1 to 2 g, usually administered 3 times daily, for treatment of bacteraemia and infections of the lower respiratory tract, urinary tract, pelvis and skin and skin structures. Furthermore, cefepime was as effective as ceftazidime and piperacillin or mezlocillin in combination with gentamicin when administered as empirical treatment for fever in patients with neutropenia. A limited number of trials have found cefepime to be as effective as cefotaxime for the treatment of gynaecological and lower respiratory tract infections. Similarly, cefepime 2 g twice daily intravenously (alone or in combination with metronidazole) was as effective as gentamicin in combination with mezlocillin or clindamycin, respectively, for the treatment of intra-abdominal infection. Cefepime has a linear pharmacokinetic profile, an elimination half-life of approximately 2 hours and is primarily excreted by renal mechanisms as unchanged drug. Cefepime has a tolerability profile similar to that of other parenteral cephalosporins; adverse events are primarily gastrointestinal in nature. A total of 1.4 and 2.9% of patients receiving cefepime < or = 2 g/day and > 2 g/day, respectively, required treatment withdrawal as a result of any adverse event. Thus, cefepime has the advantage of an improved spectrum of antibacterial activity, and is less susceptible to hydrolysis by some beta-lactamases, compared with third generation cephalosporins. Despite these advantages, cefepime has not been found to be more effective than ceftazidime and cefotaxime in clinical trials, although most trials selected patients with organisms sensitive in vitro to both comparator agents. Further trials, particularly in areas of widespread bacterial resistance, are required to confirm the positioning of cefepime for treatment of serious infection, and in particular to further explore whether its potential advantages result in clinical benefits.