Real-life experience with IV fosfomycin in Canada: Results from the Canadian LEadership on Antimicrobial Real-life usage (CLEAR) registry

Objectives: Data on the use of intravenous (IV) fosfomycin in Canada are limited. Using data captured by the C anadian LE adership on A ntimicrobial R eal-life usage (CLEAR) registry, we report the use of IV fosfomycin in Canadian patients.Methods: The CLEAR registry uses the web-based data management program, REDCapTM ( https://rcsurvey. radyfhs.umanitoba.ca/surveys/?s=F7JXNDFXEF ) to facilitate clinicians' entering of details associated with their clinical experiences using IV fosfomycin.Results: Data were available for 59 patients treated with IV fosfomycin. The most common infections treated were: bacteraemia or sepsis (25.4% of patients), complicated urinary tract infection (20.3%), ventilator-associated bacterial pneumonia (18.6%), and hospital-acquired pneumonia (13.6%). IV fos-fomycin was used to treat Gram-negative (88.1%) and Gram-positive (10.2%) infections. The most com-mon pathogens treated were carbapenem-resistant Enterobacterales (44.1%), multidrug-resistant Pseu-domonas aeruginosa (18.6%), vancomycin-resistant Enterococcus faecium (5.1%), and methicillin-resistant Staphylococcus aureus (3.4%). IV fosfomycin was primarily used due to resistance to initially prescribed therapies (69.5%), frequently in combination with other agents (86.4%). Microbiological success (eradica-tion/presumed eradication) occurred in 77.4% of patients, and clinical success (clinical cure/improvement) occurred in 62.5%. Overall, 15.3% of patients died because of their infection. Adverse effects were not documented in 73.1% of patients, and no patient discontinued therapy because of an adverse effect.Conclusions: In Canada, IV fosfomycin is used primarily as directed therapy to treat a variety of severe infections caused by Gram-negative and Gram-positive bacteria. It is primarily used in patients infected with bacteria resistant to other agents and as part of combination therapy. Its use is associated with relatively high microbiological and clinical cure rates, and it has an excellent safety profile.(c) 2023 The Author(s). Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Automated summary

Based on data from the CLEAR registry, this study reports the use of intravenous fosfomycin in the treatment of severe infections in Canadian patients. The results indicate that fosfomycin is primarily used for Gram-negative and Gram-positive bacteria resistant to other agents, and it shows high microbiological and clinical cure rates when used in combination therapy.