Background and Importance Antimicrobial resistance is a serious health threat. In Italy there are 56,600 total cases of resistant infections. Cefiderocol is an antibacterial for systemic use belonging to the class of siderophore cephalosporins. It is indicated for the treatment of serious infections caused by aerobic gram – (g-) organisms in adults with limited therapeutic options.

Aim and Objectives Describe the use of cefiderocol in real clinical practice and compare its effectiveness data with those present in the literature.

Material and Methods A single-centre retrospective observational study was conducted taking into account cefiderocol prescriptions in the period from April-22 to September-23. The data were extrapolated from a computerised personalised prescription system and from a computerised laboratory test data collection system. Personal data (age and sex), etiological agent, antibiogram, average daily dose, duration of therapy, cause of hospitalisation and hospitalisation department were analysed. The effectiveness of the therapy was obtained from the outcome of the microbiological examination at the end of administration.

Results 48 patients were enrolled with an average age of 72.5 years (26–95) of which 62% were male. 96% of patients had a g- infection, of which 35% also showed positivity for gram+ (g+). The most isolated bacterial strains were respectively: Acinetobacter baumanii (87%), Stenotrophomonas maltophilia (17%) and Klebsiella pneumoniae (17%). 69% of patients showed susceptibility to colistin antibiogram testing. On average patients received a daily dose of 4.5g (1–8). The average duration of therapy was 6 days (1–39) with 71% of patients receiving therapy in a period of 5> days <21. 17% of patients received therapy for <5 days and 12% >21 days. The causes of hospitalisation were 71% infections, 13% surgical, 12% organ failure. The greatest number of prescriptions comes from the departments of: infectious diseases (25%), resuscitation (21%) and geriatrics (17%). After cefiderocol administration, 52% of patients tested negative for g- culture.

Conclusion and Relevance Cefiderocol showed effectiveness comparable to that reported in the CREDIBLE-CR and APEKS-NP phase III clinical trials (58.3%).¹ No treatments were suspended due to toxicity. It is useful to evaluate the follow-up of patients particularly those who showed sensitivity to colistin.

References and/or Acknowledgements 1. Timsit J-F, et al. Clinical Infectious Diseases. 2022;75(6):1081–4.

Conflict of Interest No conflict of interest.