Activity of Omadacycline Alone and in Combination against Carbapenem-Nonsusceptible Acinetobacter baumannii with Varying Minocycline Susceptibility

Abstract

Treatment of infections due to Acinetobacter baumannii often involves the use of multiple antibiotics simultaneously as combination therapy, but it is unknown which antibiotics are best used together. Tetracycline agents such as minocycline and tigecycline maintain good activity against A. baumannii and are often used with one or more other agents to achieve better killing of the bacteria. Omadacycline is a new tetracycline that may have a role in the treatment of A. baumannii, but no data are available evaluating its interaction with other commonly used drugs such as polymyxin B and sulbactam. Therefore, the purpose of this study was to investigate the antibacterial activity of omadacycline when combined with one or more other agents against carbapenem-resistant strains of A. baumannii. These findings may then be used to design confirmatory studies that could help decide what drugs work best together and what combination of agents should be used for patients.