Update on the activity of delafloxacin against acute bacterial skin and skin-structure infection isolates from European hospitals (2014–2019)

Abstract

ObjectivesDelafloxacin is a broad-spectrum anionic fluoroquinolone with activity against Gram-positive and Gram-negative organisms, including methicillin-resistant Staphylococcus aureus. Both oral and intravenous formulations were approved for use in the treatment of acute bacterial skin and skin-structure infections (ABSSSIs) due to Gram-positive and Gram-negative organisms by the US Food and Drug Administration (2017) and European Medicines Agency (2019), and for community-acquired bacterial pneumonia by the FDA (2019). The SENTRY Antimicrobial Surveillance Program has monitored the susceptibility of delafloxacin in the USA and Europe since 2014. The purpose of this study is to provide an update on delafloxacin activity against ABSSSI isolates primarily collected from hospitalised patients in Europe. MethodsA total of 11,866 non-duplicate ABSSSI isolates were collected from 2014 to 2019 from 46 European medical centres in 24 countries. Susceptibilities were determined by broth microdilution. Results were interpreted using European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints (2020). ResultsThe most common isolate wasS. aureus (37.8%; n = 4484), followed by Escherichia coli (11.0%) and Streptococcus spp. (10.0%). Delafloxacin susceptibility for S. aureus was 92.4% (MIC50/90, ≤0.004/0.25 mg/L), streptococci 98.4% and E. coli 58.1%. Delafloxacin was more active against S. aureus than levofloxacin (84.0% intermediate; MIC50/90, 0.25/>4 mg/L) and moxifloxacin (84.3% susceptible; MIC50/90, ≤0.06/2 mg/L). Susceptibility of E. coli was similar for the three quinolones. ConclusionsDelafloxacin had broad-spectrum activity and improved potency against Gram-positive pathogens compared with levofloxacin and moxifloxacin. These data suggest that delafloxacin may be a useful therapeutic choice for the most common causes of ABSSSI.