PHARMACOECONOMIC ANALYSIS OF AMPICILLIN-SULBACTAM VERSUS CEFOXITIN INTHE TREATMENT OF INTRAABDOMINAL INFECTIONS

We conducted a retrospective pharmacoeconomic analysis of a prospectiv e, multicenter, double-blind, randomized, controlled trial comparing t he beta-lactamase inhibitor combination ampicillin-sulbactam (96 patie nts) and the cephalosporin cefoxitin (101) in the treatment of intraab dominal infections. An institutional perspective was adopted for the a nalysis. The primary outcomes of interest were cure and failure rates, development of new infection, and antibiotic-related adverse events. Epidemiologic data pertaining to outcomes was retrieved primarily from the trial, although results of other published studies were taken int o consideration through extensive sensitivity analyses. Data pertainin g to potential resource use and economic impact were retrieved mainly from the University Health Consortium and hospital-specific sources. W hen considering only costs associated with drug acquisition through co st-minimization analysis, a potential savings of $37.24/patient may be realized with ampicillin-sulbactam relative to cefoxitin based on an average 7-day regimen. Outcome data collected for the entire hospitali zation during the trial revealed an approximately 9% greater frequency of failure with cefoxitin relative to ampicillin-sulbactam. When cons idering all outcomes of interest in the initial base-case analysis, a potential cost savings of approximately $890/patient may be realized w ith ampicillin-sulbactam relative to cefoxitin. In assessing the impac t of the significant variability in probability and cost estimates, Mo nte Carlo analysis revealed a savings of $425/patient for ampicillin-s ulbactam over cefoxitin (95% CI $618-1516). Given the model assumption s, our analysis suggests a 78% certainty level that savings will be ex perienced when ampicillin-sulbactam is chosen over cefoxitin.