Comparative effects of ceftazidime two or three times daily in patients with skin and skin structure infections

Background: Skin and skin structure, infections are among the most common infectious diagnoses in both the hospital and community settings. If untreated, these infections can produce serious complications. Successful antimicrobial therapy for these infections requires coverage against the causative pathogens, particularly Staphylococcus aureus. Objective: This randomized, single-blind, multicenter study was designed to compare the efficacy and safety of intravenous ceftazidime 2 g given two times daily (BID) with that of intravenous ceftazidime 1 g given three times daily (TID) for the treatment of skin and skin structure infections caused by ceftazidime-sensitive pathogens. Methods: Adults (≥ 18 years) were eligible for enrollment if they were hospitalized or in home health care settings and they had a skin or skin structure infection caused by a ceftazidime-sensitive pathogen. Patients were randomly assigned to receive ceftazidime 2 g every 12 h or ceftazidime 1 g every 8 h as an intermittent infusion over 15-30 min. Treatment was continued for 2-3 days beyond the time the patient became asymptomatic or evidence of bacterial eradication was obtained; however, total treatment duration had to be at least 5 days. Patients were assessed for their clinical and bacteriological response at the end of treatment and for their clinical response at follow-up. Results: A total of 80% patients were enrolled in the study, 406 of whom received ceftazidime 2 g BID and 400 of whom received ceftazidime 1 g TID. Both treatments were administered for a mean duration of 9 days. At the end of therapy, 248 of 264 (94%) clinically evaluable patients receiving ceftazidime BID and 258 of 275 (94%) clinically evaluable patients receiving ceftazidime TID achieved clinical cure or improvement (p = 0.953). Pathogens were eradicated or presumed to be eradicated from 217 of 256 (85%) bacteriologically evaluable patients receiving ceftazidime BID and from 228 of 266 (86%) bacteriologically evaluable patients receiving ceftazidime TID (p = 0.760). Of 1131 isolates, the most common pathogens were S. aureus (30%) and Pseudomonas aeruginosa (10%). Both regimens were well tolerated with only 13 patients (3%) in the BID group and 16 patients (4%) in the TID group withdrawing because of an adverse event. Conclusions: These data indicate that ceftazidime 2 g given twice daily is as effective as ceftazidime 1 g given three times daily for the treatment of skin and skin structure infections. In addition, the twice- daily regimen has the advantage of convenience.