β-Lactamase inhibitors, cefiderocol and delafloxacin: evaluating promising antibiotics options for Pseudomonas aeruginosa in adults with cystic fibrosis.

Pseudomonas aeruginosa infections in cystic fibrosis (CF) often present therapeutic challenges due to acquired resistance. This study analyzed 178 strains from adult CF patients at a single French university hospital. High in vitro activity was observed for newer antibiotics such as ceftolozane-tazobactam (83% susceptibility), ceftazidime-avibactam (85% susceptibility), and cefiderocol (89% susceptibility). Delafloxacin also showed promising activity, with 93% of the isolates exhibiting MICs below the EUCAST epidemiological cut-off value. Results emphasize the potential utility of these agents.