Study of CeftazidimeAvibactam or Cefiderocol, With or Without Fosfomycin, for Treating Difficult Gram-negative Infections

What this Trial Is About

This research investigates the pharmacokinetics and pharmacodynamics PKPD of antibiotics ceftazidimeavibactam CAZAVI, cefiderocol CEF, and fosfomycin FOS in patients with difficult-to-treat Gram-negative bacterial infections. The study aims to optimize antibiotic dosing using Therapeutic Drug Monitoring TDM to improve outcomes, especially in high-risk patients such as those with pneumonia or renal disease. It also focuses on pediatric use, where CAZAVI is approved for children older than 3 months but cefiderocol is not. Patients of any age with infections caused by difficult-to-treat Gram-negative bacteria are observed while receiving treatment with CAZAVI alone, CEF alone, or in combination with FOS. The study does not assign treatments but monitors patients treated with these regimens in clinical practice. The primary goal is to evaluate how well these treatments achieve predefined PKPD efficacy targets. During the study, researchers assess clinical biomarkers, microbiological eradication, and protein biomarkers from the start of treatment up to 7 days, with follow-up monitoring for relapse, reinfection, and mortality over three months. The study uses data collected during routine care, including biomarker trends and microbiological tests, to understand treatment effects and optimize dosing strategies.

PK/PD Analysis of Ceftazidime/Avibactam or Cefiderocol With or Without Fosfomycin for the Treatment of Difficult To-treat Gram-negative Infections