Lipopeptide Paenipeptin Analogues Potentiate Clarithromycin and Rifampin against Carbapenem-Resistant Pathogens.

Two paenipeptin analogues at 4 μg/ml potentiated clarithromycin and rifampin against carbapenem-resistant Acinetobacter baumannii and Klebsiella pneumoniae strains. The combined treatment significantly increased their antibacterial efficacy in a microbiological medium and in human serum in vitro at therapeutically relevant concentrations. Moreover, these two paenipeptin analogues showed low cytotoxicity against a human kidney cell line. Therefore, combination therapy with paenipeptins may be an option for the treatment of antibiotic-resistant bacterial infections.