In vitro antibacterial activities of cefiderocol against Gram-negative clinical strains isolated from China in 2020

Abstract

Objectives: Cefiderocol (CFDC) is a parenteral siderophore cephalosporin that is active against Gram-negative bacteria, including carbapenem-resistant isolates. We report the in vitro activity of CFDC and other antibiotics against 1738 clinical isolates of Gram-negative bacilli (GNB) provided by five medical centres in five provinces of China in 2020 METHODS: Antibiotic susceptibility testing was performed using the Clinical and Laboratory Standards Institute broth microdilution method.

Results: Against Pseudomonas aeruginosa and Acinetobacter Spp., the CFDC concentration inhibiting the growth of 90% of the isolates (MIC₉₀) (0.5 μg/mL) was identical and did not change by the carbapenem resistance phenotype. The susceptibility rate of P. aeruginosa and Acinetobacter Spp. to CFDC was high (> 98%) and was similar against isolates with and without meropenem resistance. The MIC of CFDC for all Stenotrophomonas maltophilia isolates (20 isolates) was ≤1 μg/mL and the MIC₉₀ was 0.12 μg/mL. Considerable differences were noted in the susceptibility to CFDC between all tested Enterobacterales isolates and meropenem-non-susceptible Enterobacterales isolates. The MIC₉₀ of CFDC was 1 μg/mL for all tested Enterobacterales isolates and 8 μg/mL for meropenem-non-susceptible Enterobacterales isolates.

Conclusions: CFDC demonstrated potent in vitro activity against a recent collection of clinical isolates, including meropenem-non-susceptible isolates, obtained from medical centres in mainland China.

Keywords: Carbapenem-non-susceptible; Cefiderocol; Gram-negative bacilli.