Background and importance Cabazitaxel is an antineoplastic agent indicated for the treatment of adult patients with metastatic castration resistant prostate cancer, previously treated with a docetaxel containing regimen. The formulation available on the market consists of a vial of concentrate which, after dilution, makes 60 mg of drug available. The recommended dose of cabazitaxel is 25 mg/m² administered every 3 weeks and generally doses range from 20 to 50 mg. This results in waste with a strong economic impact considering the cost of the drug. From January to September 2019, 12 patients were treated with cabazitaxel in hospital for a total of 64 administrations (average dose of 37 mg) on 49 different days. Consumption was increased compared with the previous year (in 2018 from January to September 7 patients were treated and 42 administrations). It is appropriate to check the advantages of introducing drug day (administration of the drug on the same day of the week for all patients requiring therapy).

Aim and objectives The objective of the study was to verify the current wastage of cabazitaxel, and the potential waste with the introduction of drug day.

Material and methods Leftover drug was calculated for each day of administration (49 days). In the case of multiple administrations on the same day, leftover drug was calculated based on vial sharing. The same method was used to calculate leftover drug for every week of therapy, as if the therapies had been administered on the same day (drug day).

Results In 9 months, 2370 mg of cabazitaxel were administered and the waste calculated from leftover of single therapy days was 1350 mg (+57% compared with ideal consumption). Projecting consumption and waste at 12 months gives an annual consumption of 4960 mg of cabazitaxel (83 vials, of which 30 are considered waste).

With the introduction of drug day, waste would decrease to 810 mg (+34% compared with ideal consumption) and the projection would lead to an annual consumption of 4240 mg (71 vials, of which 18 would be considered as waste).

Conclusion and relevance The introduction of drug day for cabazitaxel is fundamental to reduce waste, optimise resources and safeguard costs.

References and/or acknowledgements No conflict of interest.