Background and importance Boosting biosimilars is an indispensable approach in conducting cost savings management in healthcare systems. In fact, biosimilars can provide similar effectiveness and safety to originators but with lower costs, and can increase market competition.

Aim and objectives The purpose of this paper was to demonstrate the economic advantage of a trastuzumab biosimilar in real practice, showing and comparing costs and consumption during the period 2018–2019.

Material and methods To conduct this analysis, patients, type of prescription (originator or biosimilar), number of cycles, administered milligrams and purchase prices, during the period 2018–2019, were extrapolated from pharmacy software and matched. A simulation was also performed to estimate potential savings, based on three scenarios of different biosimilar penetration rates (50%, 75% and 100%) and using actual costs.

Results Compared with 2018, during 2019, the number of treated patients remained similar (102 vs 98) and both a reduction of administered units of trastuzumab originator (TO) (−1383) and a growing number of prescriptions of trastuzumab biosimilar (TB) (+833 units) were observed. Costs of TO decreased from 3.28€/mg to 2.58€/mg, while average TB cost was 1.07€/mg in 2019. TB accounted for 24% of trastuzumab prescriptions but with only 11% of total costs, resulting in a reduction in total expenditure of 1 045 540€ (from 2 294 366€ spent in 2018 to 1 248 826€ spent in 2019). In addition, a simulation was performed considering three hypothetical scenarios with different penetration rates of TB in the market share (50%, 75% and 100%). The achievable savings would be 236 836€, 468 382€ and 698 185€, respectively.

Conclusion and relevance Currently, cost savings and rationalisation policy are playing an essential role in healthcare systems, and biosimilars represent a great opportunity to reallocate available resources. This study demonstrated that enhancing a trastuzumab biosimilar is a good strategy for the sustainability of care. Trastuzumab costs decreased while the number of patients remained similar. This positive result was due to both the introduction of new biosimilars and the reduction of the costs of the originators. In summary, biosimilars constitute an efficient strategy for the sustainability of national health services, allowing resource reallocation and access to care to a larger number of patients.

Conflict of interest No conflict of interest