Clinical Research Directory

Real-world Effectiveness of Cefiderocol Versus Aztreonam/Avibactam

CEFAVI is an observational study that compares the real-world effectiveness of two antibiotics, cefiderocol and aztreonam/avibactam, in patients with infections caused by Gram-negative bacteria that produce metallo-β-lactamases (MBLs). The study will collect and analyze clinical and microbiological information from patients treated with either antibiotic as part of routine clinical care. The aim is to better understand the effectiveness, microbiological response, and safety of these treatments in real-world clinical practice.

Different Administration Regimens of CAZ-AVI in Combination With ATM for the Treatment of CR-GNB

Metallo-β-lactamase-producing carbapenem-resistant Gram-negative bacteria (MBL-CR-GNB), due to their capacity to hydrolyze almost all β-lactam antibiotics, have become a critical global threat in antimicrobial resistance. Current novel β-lactamase inhibitors (e.g., avibactam, relebactam, vaborbactam) only inhibit serine enzymes and are ineffective against metallo-β-lactamases (MBL), severely limiting clinical treatment options. Aztreonam (ATM) is inherently stable against MBL, while avibactam (AVI) inhibits co-produced serine β-lactamases (e.g., KPC, OXA-48). Their combination achieves complementary synergistic antibacterial effects. The ceftazidime-avibactam plus aztreonam (CZA+ATM) regimen, operating via the mechanism of "avibactam protecting aztreonam", has demonstrated synergistic bactericidal activity against NDM, VIM, IMP and other MBL-producers in multiple real-world and clinical studies, significantly reducing infection-related mortality.However, although current domestic and international guidelines recommend the CZA+ATM combination for MBL infections, there is no consensus on optimal infusion strategies. Based on the above, this study hypothesizes that in patients with complicated infections caused by MBL-producing CR-GNB, different infusion modalities of ceftazidime-avibactam combined with aztreonam-concomitant infusion versus sequential infusion-will show no significant differences in PK/PD target attainment rates, clinical cure rates, microbiological eradication rates, or all-cause mortality, without increasing the risk of adverse events.