Tigecycline: A novel broad-spectrum antimicrobial

Objective: To review the literature on tigecycline, a novel antibiotic. Data Sources: References were identified through MEDLINE (1966-February 2007) and International Pharmaceutical Abstracts (1970-February 2007) databases, using the key words tigecycline, glycylcycline, complicated skin and skin structure infections (cSSSI), complicated intraabdominal infections (cIAI), and in vitro. Additional articles for this review were identified by reviewing the bibliographies of articles cited. The package insert was also used as a reference. Study Selection and Data Extraction: In vitro, clinical, and pharmacokinetic studies evaluating tigecycline's safety and efficacy were selected. Data Synthesis: A tigecycline 100 mg intravenous loading dose followed by an intravenous infusion of 50 mg every 12 hours was shown in clinical trials to be as effective as comparator antibiotics in treating cSSSI and cIAI. Tigecycline has a broad spectrum of activity that includes many resistant bacteria with few treatment options, such as methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase-producing bacteria such as Escherichia coli and Klebsiella pneumoniae. In cSSSI studies, tigecycline was found to be noninferior to vancomycin plus aztreonam with test-of-cure rates of 86.5% and 88.6%, respectively. Tigecycline was also found to be noninferior to imipenem/ cilastatin in clAI studies; clinical cure rates were 86.1% and 86.2%, respectively. In vitro activity has been demonstrated against other multidrug-resistant microorganisms of concern, such as Acinetobacter spp. Although it has a broad spectrum of activity, tigecycline has inadequate activity against Pseudomonas spp. Nausea and vomiting were the most frequently reported adverse effects. Conclusions: Tigecycline is approved for the treatment of cSSSI and clAI infections. To date, little resistance to tigecycline has been reported; however, with widespread use of the drug, resistance will likely occur. Since published studies have not dealt with seriously ill patients, it is recommended that, until further studies have been completed, other agents be used in the treatment of these patients unless no option other than tigecycline exists.