Budget Impact Analysis of the Introduction of a Trastuzumab Biosimilar for HER2-Positive Breast Cancer in China

Abstract

Background and objective: Biosimilars provide the possibility to reduce the high expenditure on biologic drugs and expand access to effective but less expensive treatments. Biosimilars of trastuzumab showed significant cost savings from the payer's perspective in the USA and Europe. After 2020, with the first approval of a trastuzumab biosimilar in China, it became feasible for biosimilar switching for trastuzumab. However, the economic impact of switching to a trastuzumab biosimilar was not evaluated. A budget impact model was constructed from a payer's perspective of China to demonstrate the economic impact of the introduction of a biosimilar trastuzumab in the treatment of human epidermal growth factor receptor 2-positive breast cancer.

Methods: This budget impact model was based on disease incidence to estimate the net budget impact using epidemiological data from the literature, financial reports from manufacturers on the market shares of originator trastuzumab (Herceptin^®) or the biosimilar, and localized direct costs. The budget impact was estimated for 5 years after the introduction of the first-approved trastuzumab biosimilar in China. Furthermore, two scenarios were simulated in this study to estimate the budget impact of biosimilars within: (1) real-world practice and (2) the policy of volume-based procurement.

Results: Analyses of the base-case and scenario results implied that adoption of a trastuzumab biosimilar would lead to an expenditure decrease. The average total cost savings over 5 years was estimated to be US$46,651,348, with a range from $10,306,611 in year 1 to $60,821,822 in year 5. The cost savings could benefit an additional 654-3858 patients with breast cancer. If utilizing costs from real-world practice, the introduction of a trastuzumab biosimilar could help an additional 2237-13,203 patients get access to human epidermal growth factor receptor 2-positive targeted therapy. When volume-based procurement was carried out after year 4, $672,366,180 could be saved annually.

Conclusions: This budget impact analysis emphasized the positive effects of adopting a trastuzumab biosimilar in the healthcare system of China. However, cost savings still have a large potential to decrease by regulating pricing and by the procurement policy of biosimilars.