UCLA study finds biosimilars lower costs of cancer treatment for patients and insurers
Research led by UCLA Fielding’s Dr. Tina Shih found patients paid less out of pocket, and their insurers paid far less, than for brand-name biologics.
New research led by Dr. Tina Shih, professor in UCLA Fielding’s Department of Health Policy and Management, has found that the use of low-cost alternatives (i.e. biosimilars) to biological cancer treatments can yield real savings for patients dealing with various types of cancers, including lymphoma, colorectal, and breast cancer.
The findings – “Cancer Biologics Utilization After Biosimilar Entry and Financial Implications for Payers and Patients” - were published Aug. 27 in the peer-reviewed journal JAMA Oncology. They show that patients with cancer who exclusively used biosimilars had average monthly costs that were $3,820 lower for insurers and $39.50 lower out of pocket compared with patients who exclusively used the original branded biologic drugs within the 12-month period since treatment initiation. The results provide evidence that market competition enabled by entry of biosimilars may help reduce the cost of cancer biologic drugs.
“Although the savings were substantially greater for insurers than for patients, any reduction in out-of-pocket costs may be meaningful for people facing the financial challenges of cancer care, and these savings can be used toward other treatment-related expenses or cover living expenses,” said Shih, the study’s senior author and director of the Cancer Health Economics Research Program at the UCLA Health Jonsson Comprehensive Cancer Center, as well as professor of health economics in the Department of Radiation Oncology. “Notably, the market competition introduced by biosimilars is clearly associated with lower costs for the payer and a reduction in the financial burden for patients.”
Because most patients in the study who received biosimilars started treatment with them, rather than switching from an original biologic, decisions about which drug to use when treatment begins may play an important role in increasing access to lower-cost and equally efficacious alternatives.
“The FDA has continued to take regulatory actions aimed at further unlocking biosimilar competition recently," said Dr. Xiaoyu Liu (UCLA Fielding PhD ’26), the study’s first author. "Our study findings offer further evidence to support patients, providers, and insurers in their consideration of biosimilars."
Background and Methodology
Biosimilars are highly similar to originator biologics, with no clinically meaningful differences in safety, purity, or potency, and were introduced to increase market competition, lower the price of biologics, and expand patient access by improving affordability. By the end of 2024, three anticancer biologics have experienced biosimilar entry in the US (bevacizumab, rituximab, and trastuzumab), reinforcing the need to evaluate their financial implications for payers and patients.
This retrospective cohort examined price and market share trends and payer and patient costs after biosimilar entry. It used data from the MarketScan commercial and Medicare databases from July, 2019 to December, 2024. Based on use patterns within 12 months of treatment initiation, patients were categorized into 4 groups: those who exclusively used biosimilars, exclusively used the reference product (i.e., originator biologics), switched from the reference product to biosimilars, and switched from biosimilars to the reference product. Data were analyzed between September 2025 and March 2026.
The primary study outcomes were average sales price (ASP), market share of reference products, and mean monthly payer and out-of-pocket costs within the study period.
Among 14,655 patients in this study, the mean age was 57 years, 9985 (68.1%) were female, and the most common cancers were breast cancer (5182 [35.4%]), lymphoma (4320 [29.5%]), and colorectal cancer (1998 [13.6%]). A total of 8710 patients (59.4%) exclusively used biosimilars, 4760 (32.5%) exclusively used the reference product, 1015 (6.9%) switched from the reference product to biosimilars, and 170 (1.2%) switched from biosimilars to the reference product. After biosimilar entry, the ASP of the 3 reference products declined by an average of 3.8% annually. Their market share decreased 30% annually in commercial insurance and 31.5% in the Medicare Part B market. Compared with patients who only used the reference product, those who only used biosimilars rendered a $3,820 lower mean monthly payer cost and $39.50 lower mean monthly out-of-pocket cost.
Funding
This work was partially supported by the (U.S.) National Cancer Institute under award numbers R01CA225647 and P30CA016042. The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
