How Large Is the Patent Cliff for Adalimumab in Slovenia

OBJECTIVES: Expenditures on biological medicines consume a growing fraction of Slovenia’s health budget. Although biosimilars may contribute to reduce stress on health budgets, this only holds if the increase in administered doses is accompanied by price decreases of the respective medicine. The aim of this study is to evaluate the effect of market entries of biosimilars on Slovenian healthcare expenditures. The focus will be on medicines containing adalimumab, which constitute in 2022 37.4 % of expenditures in accessible off-patent market for biological medicines.

METHODS: Data on minimum wholesale unit prices of biological medicines was collected through the European integrated price information database (EURIPID) between January 2018 and November 2023 for all EU countries (as of 2023). Price data has been collected for the original biological medicine of Adalimumab, and nine biosimilars. At each timepoint different metrics (lowest, highest and average minimum prices) were calculated. To analyze the impact of market entries of biosimilar on prices, price decreases have been calculated to periods before and the first three market entries.

RESULTS: In Slovenia, the highest minimum wholesale unit price of the originator, as well as biosimilar medicines, was below a European average price throughout the observed period. A decreasing trend in the highest, lowest, and average minimum wholesale unit prices was observed in Slovenia and other European countries. The price of the originator drops before and after market entries of biosimilars and are in the medium to high range compared to other surveyed countries.

CONCLUSIONS: Slovenian policy framework has been successful in decreasing the wholesale unit prices of both the originator as well as biosimilar, while keeping an above average number products available on the market. Price decreases related to market entries of biosimilars were most profound for first, but a clear effect of second and third biosimilars’ entries was also observed.