# Comparative effectiveness of antimicrobial regimens for pneumonia caused by drug-resistant Acinetobacter baumannii: a network meta-analysis including cefiderocol and inhaled therapies

## TL;DR

This study compares different antibiotic treatments for pneumonia caused by drug-resistant Acinetobacter baumannii, finding that cefiderocol-based regimens are most effective at reducing mortality and improving outcomes.

## Contribution

The study introduces a network meta-analysis comparing cefiderocol and inhaled therapies for drug-resistant Acinetobacter pneumonia, identifying cefiderocol as a top treatment.

## Key findings

- Cefiderocol-containing regimens reduced all-cause mortality by 76% compared to other therapies.
- Inhaled colistin improved clinical success and microbiological eradication more than other regimens.
- Tigecycline monotherapy had the lowest risk of nephrotoxicity.

## Abstract

The objective of this network meta-analysis was to evaluate and compare the efficacy and safety of different antimicrobial regimens used in the treatment of pneumonia caused by extensively drug-resistant (XDR) or multidrug-resistant (MDR) Acinetobacter baumannii (AB). Given the increasing prevalence of resistant strains, identifying optimal treatment strategies is crucial.

We systematically analyzed data from randomized controlled trials and retrospective cohort studies retrieved from major electronic databases. The included studies evaluated all-cause mortality, clinical success, microbiological eradication, and nephrotoxicity associated with cefiderocol, intravenous (IV) colistin, inhaled colistin, igecycline, sulbactam, and their combination-based regimens in patients with MDR/XDR-AB pneumonia.

A total of 19 eligible studies involving 1,941 participants were included in the analysis. Cefiderocol-containing regimens demonstrated the greatest reduction in all-cause mortality (odds ratio (OR): 0.24; 95% CI: 0.09–0.68) compared to other therapies. In terms of clinical success, cefiderocol-containing regimens (OR: 2.77; 95% CI: 1.07–7.19) and inhaled colistin (OR: 2.61; 95% CI: 1.14–5.99) were significantly more effective than other regimens. Microbiological eradication was most notable with inhaled colistin, and with IV colistin combined with sulbactam or tigecycline. However, nephrotoxicity was commonly observed with IV colistin, while tigecycline monotherapy showed the lowest nephrotoxicity risk (OR: 0.15; 95% CI: 0.04–0.60).

This study provides comprehensive evidence on current and emerging treatments for MDR/XDR-AB pneumonia. Cefiderocol-containing regimens appears to be the most effective regimen in reducing mortality and improving clinical outcomes, though nephrotoxicity risks must be carefully considered when using IV colistin-based therapies.

Not applicable.

The online version contains supplementary material available at 10.1186/s12879-026-12640-z.