Investigational antibiotic cefepime/zidebactam as a therapeutic option for the treatment of an unyielding empyema in a paediatric patient caused by extensively drug-resistant Pseudomonas aeruginosa: a case report

Treatment option for the infections caused by MBL-producing P. aeruginosa is severely limited. Cefepime/zidebactam (WCK 5222) is a novel β-lactam/ β-lactam-enhancer combination, currently in global Phase 3 clinical development. It is reported to show a broad-spectrum in vitro activity and translational efficacy in non-clinical PK/PD models against carbapenem-resistant Gram-negative bacteria including MBL-producing P. aeruginosa. We present a case of a 13-year-old girl, suffering from tuberculosis with a refractory lung empyema caused by NDM-producing, XDR P. aeruginosa who did not respond to several rounds of colistin or aztreonam plus ceftazidime/avibactam therapies albeit effective source control, over 4 months period. The infecting organism was found to be susceptible to cefepime/zidebactam. After obtaining informed consent and necessary approvals, the patient was treated under compassionate ground. The patient was treated with adult dose regimen of cefepime/zidebactam (due to higher body weight) for 21 days that led to clinical and microbiological cure. This case highlights both severity of the antimicrobial resistance and hope offered by an under-trial novel antibiotic.