Clinafloxacin versus piperacillin/tazobactam in the 'treatment of severe skin and soft-tissue infections in adults at a veterans affairs medical center

Background: Severe skin and soft-tissue infections (SSTIs), particularly diabetic foot infections, are a source of considerable morbidity and mortality. Inappropriate antimicrobial therapy may contribute to the increasing emergence of bacterial resistance, as well as to increased health care costs. Thus, there is a continuing search for reasonably safe, well-tolerated, and effective antimicrobial agents that are less susceptible to the development of resistance than older agents. Objective: The Department of Veterans Affairs (VA) Medical Center in Nashville, Tennessee, was I site in a multicenter, Phase III, randomized, investigator-blinded clinical trial comparing the safety and efficacy of clinafloxacin with those of piperacillin/tazobactam in the treatment of adult patients with SSTI. Methods: Over an 18-month period, patients aged greater than or equal to18 years with physical findings of acute bacterial SSTI requiring hospitalization and intravenous antimicrobial therapy were randomized in a 1:1 ratio to receive either clinafloxacin 200 mg IV every 12 hours or piperacillin/tazobactam 3.375 g IV every 6 hours. After a minimum of 3 days of intravenous therapy, a switch to oral therapy with clinafloxacin 200 mg PO every 12 hours or amoxicillin/clavulanate 500 mg PO every 8 hours could be made in the respective treatment groups. Results: The center enrolled 84 patients (42 in each group), all but I of whom were male, reflecting the typical VA medical center population. The mean age was 60 years (range, 36-80 years) in the clinafloxacin group and 65 years (range, 35-87) in the piperacillin/tazobactam group; the latter group was significantly older (P = 0.0482), which could have affected recovery rates. Sixty-six patients were white and 18 were black. The mean (+/-SD) duration of treatment was 10.69 +/- 5.34 days in the clinafloxacin group and 12.07 +/- 5.06 days in the piperacillin/tazobactam group; the mean length of stay was 10.83 +/- 10.28 days and 14.95 +/- 19.20 days, respectively. Fifty-three (63%) patients were switched to oral therapy (2 1 in the clinafloxacin group, 32 in the piperacillin/tazobactam group). The most commonly isolated pathogens were Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Enterobacter cloacae. Clinical cure rates and microbiologic eradication rates were similar between the 2 treatments. The piperacillin/ tazobactam arm experienced more all-cause adverse events than the clinafloxacin arm, although the difference was not statistically significant. The clinafloxacin arm experienced significantly more adverse events (eg, photosensitivity) that were judged by the investigator to be drug related (P = 0.034). Conclusions: In this study population of hospitalized adults, clinafloxacin was as effective as piperacillin/tazobactam in the treatment of complicated SSTIs. Appropriate precautions must be taken against exposure to sunlight and ultraviolet light in patients receiving clinafloxacin, and adequate monitoring is necessary. Further investigation is necessary into how the phototoxic effects of the fluoroquinolones can be limited.