# Efficacy of cefiderocol in combination with xeruborbactam versus taniborbactam against cefiderocol-resistant NDM-producing Pseudomonas aeruginosa

## TL;DR

This study compares two drugs in restoring effectiveness of an antibiotic against a drug-resistant strain of Pseudomonas aeruginosa.

## Contribution

The study reveals that taniborbactam, but not xeruborbactam, effectively reverses resistance in NDM-producing Pseudomonas aeruginosa.

## Key findings

- Taniborbactam restored cefiderocol susceptibility in 95.2% of NDM-positive Pseudomonas aeruginosa isolates.
- Xeruborbactam had no effect on reversing resistance in these isolates.
- An isolate unresponsive to taniborbactam carried multiple copies of blaNDM-1.

## Abstract

We evaluated the in vitro activity of cefiderocol in combination with either taniborbactam or xeruborbactam against cefiderocol-resistant, blaNDM-positive Pseudomonas aeruginosa clinical isolates from Vietnam and Nigeria. Taniborbactam restored cefiderocol susceptibility in most isolates (20/21, 95.2%), while xeruborbactam had no effect. Resistance was reversed by dipicolinic acid, which confirmed New-Delhi Metallo-β-Lactamase (NDM-mediated) resistance. One isolate that was unresponsive to taniborbactam carried multiple copies of blaNDM-1. These findings highlight the species-specific limitations of xeruborbactam in P. aeruginosa.