Background and Importance Clostridium difficile is the most common cause of infectious diarrhoea in hospitalised patients and causes great morbidity due to the high percentage of recurrence. Bezlotoxumab was the first humanised monoclonal antibody against C.difficile toxin B approved for prevention of recurrent Clostridium difficile infection (CDI) in high-risk adults in conjunction with standard of care antibiotics. Bezlotoxumab vial power is 1,000 mg, is given as a one-time infusion in recommended dose of 10 mg/kg over 60 minutes. New guidelines on the management of CDI have been published in 2021: ACG and IDSA/SHEA, which recommend using bezlotoxumab in patients with a high risk of recurrence.

In order to reduce economic impact of the administration of bezlotoxumab, our centre promoted scheduling selected patients on the same day to use the rest of the vials.

Aim and Objectives To assess the economic impact of the appointment strategy in patients treated with bezlotoxumab.

Material and Methods A retrospective analysis of pharmaceutical expenditure of bezlotoxumab prescribed for CDI was conducted from June 2019 to August 2022. Data collected were number of patients treated with bezlotoxumab, weight, date of infusion, number of vials required. Data were collected from electronic prescribing program and economic software.

Results 45 adult patients were included in the study. They all received bezlotoxumab for CDI at high risk of recurrence, in single infusion of 10 mg/kg. 24 patients (53.3%) were cited to prevent vial waste. 21 patients (46.7%) required a complete vial: due to their weight, difficulties in making an appointment, or both. Of 24 patients, median weight was 50 kg (rank 34-66 kg).

In the period of our study, 35 vials of bezlotoxumab were used. Cost of bezlotoxumab vial is €1,480. Estimated expenditure was: €51,800 if patients were cited vs €66,600 if not. The cost of treatment decreased by €14,800 due to the administration appointment strategy.

Conclusion and Relevance Bezlotoxumab is an effective treatment in preventing CDI relapse in high risk recurrence patients, following guidelines. Administration appointment strategy in selected patients has proven to be efficient since more patients can be treated with the same budget.

References and/or Acknowledgements 1. Clinical Practice Guideline by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA): https://pubmed.ncbi.nlm.nih.gov/34164674/

ACG Clinical Guidelines Prevention, Diagnosis, and Treatment of Clostridioides difficile Infections: https://pubmed.ncbi.nlm.nih.gov/34003176/

Conflict of Interest No conflict of interest