Background Minimization of chemotherapy costs has become a rational goal in today’s economic environment.

Purpose To assess the cost savings achieved by optimising vial residues during chemotherapy preparation.

Materials and Methods A longitudinal prospective study was conducted in the Intravenous Chemotherapy Unit of the Pharmacy Service between 15 January and 31 March of 2012. We selected the six drugs with more potential cost saving (bevacizumab, bortezomib, liposomal doxorubicin, panitumumab, rituximab and trastuzumab). Data were collected with the Oncofarm software: number of patients, number of preparations, theoretical and actual number of vials used. For economic estimates the retail price (RRP) was used.

Results During the study period, 365 preparations were administered to 190 patients; these required the potential use of 716 vials, but actually 545 vials were used, saving 219,538€ (33% of the cost without recycling excess vials).

Data analysis showed that 81% of the total savings were achieved with only 2 drugs: bevacizumab (50%, 80 vials, €110,556) and rituximab (31%, 50 vials, €67,752). Their high frequency of use (66% of preparations and 68% of patients), high cost and greater variability of prescribed doses, justifies these results.

Theoretical average costs of the preparations analysed without managing the residues of partially-used containers were 1,790 (SD:476) €/preparation and 3,568 (SD:642) €/patient. After savings were made the averages were 499 (SD:253) €/preparation and 965 (SD:389) €/patient. Rituximab (€836/preparation, €1,063/patient), bevacizumab (€700/preparation, €1,602/patient) and panitumumab (€625/preparation, €1,111/patient) were the drugs with greater savings.

We estimated the difference between potential savings if the adjustment had been perfect and the actual saving obtained (€21,135), possibly caused by the preparation process or expiry of some reconstituted vials

Conclusions Residues management is a common practise to improve the efficiency of the preparation process. Optimizing this process of updating medicines’ stabilities, recording the opening date on the vial, checking expiries and storage conditions, achieved significant savings in the cost of treatments.

No conflict of interest.