Background Intravenous mixtures with low physicochemical stability vials could generate economic loss by wasted medication in the case of expensive drugs with individualised dosing if we treated only a few patients on different days. This is the case of infliximab.

Purpose The aim of this study was to retrospectively examine the pattern of utilisation in clinical practise (clustering patients at the same day of the week or not) and the saving costs associated with the optimization of infliximab use in the treatment of rheumatoid arthritis or Crohn’s disease.

Materials and Methods We collected data of patients treated whit infliximab during the first two months of 2012. We clustered patients by weeks, so we calculated the total weekly dose by adding the dose of each patient and total number of vials required of infliximab (clustering patients or not). Infliximab was given at dose of 3–5 mg/kg every 6–8 weeks. We calculated treatment costs between two alternatives.

Results Eighteen patients received at least one infliximab infusion during a selected observation period were studied. The mean infliximab dose administered to all the patients was 342 ± 80 mg per patient. The number of vials used was 67, if we cluster patients, and 71 without cluster patients Infliximab vial optimization allows us, for the whole year, to reduce the amount of vials from 486 to 458, with a significant saving of 13612€ by year.

Conclusions Clustering patients in a agreed day of week allows significant cost savings in the context of a regional hospital. The cost of treatment could be reduced by using infliximab vial optimization. These results could be applied for the vial optimization of some monoclonal antibodies and cytostatic agents.

No conflict of interest.