Cefiderocol: How Are Benefits and Mortality Risks

Why does cefiderocol matter for antibiotic-resistant infections?

CDC's February 2025 assessment documents how the pandemic disrupted progress against antimicrobial resistance. Hospital-onset resistant infections and associated deaths increased by at least 15% between 2019 and 2020 across seven pathogens. These historical findings help explain the continuing need for effective hospital antibiotics; they do not establish the effectiveness of any particular drug. [CDC assessment](https://www.cdc.gov/antimicrobial-resistance/data-research/threats/covid-19.html)

Cefiderocol is a siderophore cephalosporin: its iron-binding component helps it enter Gram-negative bacteria through their iron-acquisition machinery. Once inside, it disrupts construction of the bacterial cell wall. This mechanism can overcome some barriers that impede other antibiotics, although bacteria can develop resistance to cefiderocol itself. [IDSA treatment guidance](https://www.idsociety.org/practice-guideline/amr-guidance/)

Marketed as Fetroja, cefiderocol first received U.S. approval in 2019. Its labeled uses cover adults with complicated urinary tract infections, including kidney infections, and hospital-acquired or ventilator-associated bacterial pneumonia caused by specified susceptible organisms. It is administered intravenously over three hours. [Fetroja prescribing information](https://www.dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=75c0c785-38e0-4049-a6fb-b77581f5b35c)

What did clinical trials reveal about cefiderocol's mortality risk?

The CREDIBLE-CR trial randomized 152 adults with serious carbapenem-resistant Gram-negative infections; 150 received treatment. In the published analysis, 34 of 101 cefiderocol recipients and nine of 49 patients receiving best available therapy died by the end-of-study visit. These correspond to approximately 34% and 18%. The open-label study included different infection sites and organisms, with the numerical mortality excess concentrated primarily among patients with Acinetobacter infections. [CREDIBLE-CR trial](https://pubmed.ncbi.nlm.nih.gov/33058795/)

The prescribing information carries a warning about increased all-cause mortality in that trial and states that the cause remains unestablished. The finding requires attention, but it does not establish the same risk for every organism or approved use. [Fetroja mortality warning](https://www.dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=75c0c785-38e0-4049-a6fb-b77581f5b35c)

In the separate APEKS-NP pneumonia trial, mortality at day 14 was 12.4% with cefiderocol and 11.6% with high-dose, extended-infusion meropenem. Cefiderocol met the trial's noninferiority criterion, meaning the results stayed within a predefined acceptable difference. This was not proof of superiority. Because the trials studied different populations and comparisons, APEKS-NP does not resolve the CREDIBLE-CR warning. APEKS-NP was funded by manufacturer Shionogi. [APEKS-NP trial](https://pubmed.ncbi.nlm.nih.gov/33058798/)

How do specialists decide when cefiderocol is appropriate?

IDSA's 2026 guidance illustrates why the bacterial diagnosis matters. Cefiderocol is among preferred options for invasive infections caused by NDM-producing Enterobacterales, bacteria carrying an enzyme that disables many antibiotics. For invasive carbapenem-resistant Acinetobacter baumannii infections, however, IDSA treats cefiderocol as an alternative combined with another agent, generally when resistance prevents preferred therapy or while that therapy becomes available. These recommendations address specific clinical circumstances and should not be interpreted as interchangeable treatment choices. [IDSA treatment guidance](https://www.idsociety.org/practice-guideline/amr-guidance/)

Monitoring also matters after treatment begins. Kidney function affects cefiderocol dosing, and clinicians must assess whether the infection is responding. Its labeling also describes serious allergic reactions, C. difficile-associated diarrhea, and neurological adverse effects including seizures. Patients and families should promptly report suspected adverse effects to the treating team. [Fetroja prescribing information](https://www.dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=75c0c785-38e0-4049-a6fb-b77581f5b35c)