Intensive care unit (ICU)-acquired infections as a result of multidrug-resistant Gram-negative pathogens remain a serious problem in critically ill patients. Adult ICU patients who received intravenous fosfomycin were prospectively examined to assess its safety and effectiveness as an adjunct to the antimicrobial therapy of life-threatening infections caused by carbapenem-resistant Klebsiella pneumoniae. Fosfomycin was administered intravenously in 11 patients for treatment of hospital-acquired infections caused by carbapenem-resistant K. pneumoniae. Fosfomycin (2-4 g every 6 h) was administered in combination with other antibiotics. The mean +/- SD duration of treatment was 14 +/- 5.6 days. All patients had good bacteriological and clinical outcome of infection. All-cause hospital mortality was two out of 11 (18.2%) patients. No patient experienced adverse events related to the administration of fosfomycin. Intravenous fosfomycin may be a beneficial and safe adjunctive treatment in the management of life-threatening ICU-acquired infections caused by carbapenem-resistant K. pneumoniae.