The advent of biologic drugs has had a significant impact on the management of patients with cancer. However, the high costs associated with these agents can hinder treatment access for many patients and place a significant burden on healthcare systems. As several biologics have come off patent over the past few years and more are expected to do so in the near future, biosimilars are poised to play an increasingly important role in reducing healthcare costs.1
At the American Society of Clinical Oncology 2021 virtual annual meeting, results of an analysis of real-world data showed that the use of biosimilars in oncology increased exponentially in the United States during the past 2 years.2
Researchers gathered data for the analysis from 2020 prescription information (Wolters Kluwer, N = 130,836), sales data (IQVIA), and dosage information for patients taking bevacizumab (Avastin), trastuzumab (Herceptin), rituximab (Rituxan), or an FDA-approved biosimilar for these drugs (FDA Purple Book), between 2019 and 2021 (ION Solutions, N = 69,884). They discovered that in 2020, 8.2% of new prescriptions for bevacizumab, rituximab, and trastuzumab were for biosimilar versions. For bevacizumab, there are currently 2 biosimilars available; rituximab, 3; and trastuzumab, 5.
Data on the use of trastuzumab biosimilars revealed a dramatic increase from the first year of availability to the next. In the first 3 months of 2019, 7.3% of initiating first-line patients were prescribed a trastuzumab biosimilar versus the reference product. In the first quarter of 2020, when all 5 trastuzumab biosimilars had become available, the new prescriptions rate was 80.5% for patients receiving first-line treatment.
Although the uptake rates varied for individual biosimilars, there was a willingness among oncologists to switch patients from reference products to biosimilars as time went on. The investigators reported that 11.1% of patients were transitioned from reference biologics to biosimilars during treatment.
“Uptake was particularly rapid for trastuzumab biosimilars. Among patients on trastuzumab at the time of its first biosimilar launch, 18.2% switched to [the Kanjinti trastuzumab biosimilar] in the first 90 days postlaunch,” they noted.
Significant savings was an important aspect of biosimilar use in the oncology practices. Costs per biosimilar prescription were lower than the reference product prescription cost by 42.0%, 29.9%, and 89.5% for trastuzumab, rituximab, and bevacizumab, respectively.
“However, biosimilar launches had little impact on reference product pricing, with 2019 to 2020 year-over-year differences in price per prescription close to the year-over-year averages in previous years (2015-2019) for all 3 reference products,” the investigators reported.
“Uptake of biosimilars among oncology providers between 2019-2020 was rapid, although the extent of biosimilar prescribing varied among products. Biosimilars offered greatly reduced costs to providers, although reference product prices remained stable despite increased biosimilar competition,” the investigators concluded.
- Konstantinidou S, Papaspiliou A, Kokkotou E. Current and future roles of biosimilars in oncology practice. Oncol Lett. 2020;19:45-51.
- McGlynn KA, McGarry J, Patel KB, Clinton, N. Real-world trends in biosimilar prescribing among oncology providers, 2019-2021. J Clin Oncol. 2021;39(15_suppl):Abstract e18701.