OBJECTIVES: Biologics such as etanercept are considered effective but costly treatment options. SB4, an etanercept biosimilar, is available in Spain since July 2016 and its adoption has been until now slow generating minor savings for the Spanish healthcare system. This study’s objective was to assess the additional budget savings of introducing SB4 that can be achieved with a rapid biosimilar adoption in Spain.

METHODS: The cost saving potential of introducing SB4 in Spain was estimated over a two-year horizon from the payer’s perspective. Annual sales (€) of the reference product in the year prior to biosimilar entry were used assuming these to remain constant over the 2-year horizon.

Two model scenarios with different adoption rates vs the current SB4 adoption trend were compared. For the current adoption rate, the actual market share of first 5 months was used to extrapolate for year 1 (2%) and 2 (4%). Two further adoption rates were modeled based on rates seen in Germany and UK using the actual market share in year 1 and extrapolate for year 2: Germany (moderate: 20% and 50%) and UK (rapid: 50% and 80%). Prices were obtained from published sources.

RESULTS: Introduction of SB4 resulted in potential savings of €0.17m and €0.48m based on current biosimilar adoption rate in year 1 and 2, respectively. If adoption rate was increased, additional savings of €1.52m & €5.18m for the moderate and €4.06m & €9.86m for the rapid scenario could be achieved in year 1 & 2.

CONCLUSIONS: The SB4 introduction represents substantial cost-saving potential for the healthcare system in Spain. However, the slow adoption rate will generate savings of only €0.65m over a two-year horizon. Additional savings up to €13.92m could be achieved, if mechanisms are implemented, as those in UK and some regions in Germany, to support the biosimilar uptake.