Activities of Cefiderocol with Simulated Human Plasma Concentrations against Carbapenem-resistant Gram-negative Bacilli in an In Vitro Chemostat Model

Activity of cefiderocol under simulated human plasma concentrations at the recommended dosing regimen of 2 g every 8 h with a 3-h infusion were evaluated using an in vitro chemostat model. Against a total of 6 meropenem-resistant Gram-negative strains with cefiderocol MIC of 0.5 to 4 μg/ml including metallo-β-lactamase producers and carbapenem-resistant Acinetobacter baumannii, cefiderocol treatment showed bactericidal effect within 8 h, and sustained efficacy with no marked bacterial regrowth over 24 h.