Moxifloxacin QD similar to piperacillin-tazobactam and amoxicillin-clavulanate dosed multiple times a day in treatment of complicated intra-abdominal infections

Intravenous (IV) moxifloxacin followed by oral (PO) moxifloxacin, both dosed once-daily, is at least as effective in the treatment of complicated intra-abdominal infections (cIAIs) as piperacillin-tazobactam and amoxicillin-clavulanate comparator regimens dosed multiple times per day, researchers reported in the Annals of Surgery. The findings are the result of a prospective, double-blind, phase 3 comparative trial of 656 intent-to-treat (ITT) patients, 379 in which efficacy was valid to assess (183 moxifloxacin, 196 comparator).

Clinical and bacteriologic assessments, as well as laboratory testing related to cIAIs, were performed at the following intervals: pretreatment (within 24 hours prior to the initiation of therapy), during treatment (Day 3–5 or the day of the IV/PO switch if not Day 3–5), end of therapy (Day 5–14), and at the test-of-cure visit (Day 25–50 after study start). The primary efficacy variable was clinical cure rate at the test-of-cure visit, and this was stratified according to the nature of the infection (ie, hospital-acquired vs community-acquired). Hospital-acquired infections were categorized as such if the patient had been hospitalized for >2 days prior to enrollment, had an infection related to a previous surgery, and had been treated with antibiotics for ≥3 days prior to enrollment or had a medical history consistent with recent hospitalization.

In terms of bacteriologic outcomes, the eradication rate reported in moxifloxacin-treated patients was 78% compared with 77% in comparator-treated patients (95% CI, –9.9% to 8.7%). A complete breakdown of the bacteriologic eradication rates by organism for the most commonly isolated organisms can be found in Table 1. Among patients with polymicrobial infections, the mean number of different organisms isolated per patient was 3.9±1.7 in the moxifloxacin treatment arm and 4.2%±1.9 in the comparator treatment arm.

The 2 antibiotic treatment regimens also demonstrated similarities in terms of reported adverse events, with an incidence due to any cause of 84% in the moxifloxacin arm and 83% in the comparator arm. Likewise, adverse event intensity was similar between the 2 treatment groups, with the majority (88%) being mild-to-moderate in both groups.

In light of the similarities between the 2 treatment groups in terms of efficacy and adverse events, the researchers pointed out that "moxifloxacin, which can be given once-daily, can be considered a useful and convenient option for the treatment of cIAI."

SOURCE Malangoni MA, Song J, Herrington J, Choudhri S, Pertel P. Randomized controlled trial of moxifloxacin compared with piperacillin-tazobactam and amoxicillin-clavulanate for the treatment of complicated intra-abdominal infections. Ann Surg. 2006;244:204–211.