Results from a phase 2 randomised trial suggest that a new investigational antibiotic is as effective as the current standard-of-care antibiotic for the treatment of complicated urinary tract infections (UTIs) caused by several multidrug-resistant Gram-negative bacteria.
The findings, published in The Lancet Infectious Diseases , indicated that patients treated with cefiderocol, a new siderophore cephalosporin, had a higher and more sustained level of pathogen eradication, good tolerability, and similar clinical outcomes to those treated with imipenem-cilastatin.
Cefiderocol is effective in overcoming the main mechanisms of antibiotic resistance used by Gram-negative bacteria—two outer membranes that make it difficult for antibiotics to penetrate, porin channels which can adapt to block antibiotic entry, and efflux pumps that expel antibiotics back out of the cell and make them ineffective – through its novel mechanism of cell entry that utilises the bacteria’s need for iron to survive.
The findings highlight the potential of cefiderocol as an important potential new option for treating highly resistant Gram-negative bacteria.
The authors noted, however, that the study’s exclusion of patients with carbapenem-resistant infections, because the comparator was a carbapenem, was an important limitation. Ongoing clinical trials of cefiderocol’s effectiveness in pneumonia and in patients with carbapenem-resistant infections will provide additional information.