Background Bortezomib is an expensive drug with a very short stability. For subcutaneous administration each vial should be reconstituted with 1.4 mL of NaCl 0.9% (2.5 mg/mL). According to the manufacturer, reconstituted it is stable at 25°C for only 8 h. Considering the recommended dose of 1.3 mg/m² and the amount of drug per vial (3.5 mg/1.4 mL), the loss of product during preparation may be significant. However, a study published by Walker et co-authors has shown that bortezomib is stable for up to 21 days, permitting an optimisation of costs.

Purpose To evaluate the impact of the extended stability limits of bortezomib on handling practices and the optimisation of costs.

Material and methods Two periods were evaluated: before (January–September 2013) and after (January–September 2014) modification of the stability limits. From the individual preparation files, different parameters were recorded: number of patients and prescription lines, mean dose, theoretical residues, % of residues re-used, value of the residues re-used.

Results Seventy patients were included, 34 in the first period and 36 in the second one. The number of prescription lines was 584 and 452 in the first and second period, respectively. The mean dose in both periods was 2.10 mg. In the first period the theoretical residues were 311.59 mL, the % of residue re-used 56.00 mL (17.9%) and the value of the re-used residues €24,137.57. For the second period, the theoretical residues were 248.39 mL, the % of residue re-used 232.4 mL (93.7%) and the value of the re-used residues €100,170.90. The cost per dose was €983 and €677 in the first and second period, respectively.

Conclusion An extended stability limit for bortezomib as compared to that recommended by the manufacturer should lead to an improvement of manufacturing processes and significant costs savings. The re-use of residues is a real strategy to contain costs.

References and/or acknowledgements No conflict of interest