Ceftazidime/Avibactam Monotherapy Versus Other Antibiotics: Where Do We Stand?

The global rise of multi-drug resistant (MDR) pathogens, including the widespread resistance to beta-lactams through the production of β-lactamases, like extended spectrum β-lactamases (ESBLs), has led to the increasing use of last-line antibiotics such as carbapenems. Subsequently, the worldwide emergence of carbapenemase-producing pathogens poses a formidable challenge. The combination ceftazidime/avibactam (CAZ/AVI) has emerged as a pivotal agent in the management of multidrug-resistant Gram-negative infections. Avibactam, a novel β-lactamase inhibitor, demonstrates a wider spectrum of activity against Ambler Class A, C, and partially D β-lactamases in comparison to older inhibitors, thus enhancing the antimicrobial activity of ceftazidime against organisms producing ESBL and carbapenemases, such as oxacillinase (OXA)-type and Klebsiella pneumoniae Carbapenemase (KPC). This review synthesizes findings from randomized controlled trials and cohort studies, evaluating the efficacy of CAZ/AVI across diverse clinical settings, including complicated intra-abdominal infections, urinary tract infections, nosocomial pneumonia, skin and soft tissue infections, and bloodstream infections. The non-inferiority of CAZ-AVI with respect to carbapenems and superiority over polymyxins in terms of both clinical outcomes and safety are outlined, along with evidence supporting the use of CAZ/AVI in high-risk populations such as immunocompromised and critically ill patients. Overall, CAZ/AVI represents a compelling therapeutic option with favorable efficacy and safety, thus appearing as a reasonable frontline treatment for resistant Gram-negative infections.