ASCO Studies Assess Biosimilar Substitution, Adoption in Oncology Practices

Abstracts from the American Society of Clinical Oncology (ASCO) annual meeting took a look at the impact biosimilar substitution and increased biosimilar adoption had on spending within practices participating in value-based payment (VBP) models and the Oncology Care Model (OCM).

Biosimilar Substitution in VBP Models

Biosimilar substitution led to significant reductions in aggregate provider risk in the OCM, suggesting that a continuation of this potential intervention for providers to mitigate risk in VBP models for cancer care.¹

Oncology biosimilars could play a key role in managing provider risk participating in VBP models. The impact that biosimilar substitution has on risk to providers is unclear, as past research has mostly focused on the budget impact of generic adoption.

To estimate the impact of substitution on financial risk to providers in VBP models, researchers modeled the quantitative methodology of Medicare’s OCM. Biosimilars for bevacizumab, rituximab, trastuzumab, epoetin alfa, filgrastim, and pegfilgrastim were assessed. The study population contained 1620 episodes framed with the OCM methodology using Medicare Limited Data Set from 2019 to 2020 that included use of biosimilar agents.

Biosimilar substitution led to a mean cost reduction of about $1200 per eligible episode, and the proportion of practices that were above benchmark for eligible episodes was reduced by 33%. Substitution also increased the number of practices below target for eligible episodes by 42%.

The researchers said that their results suggested that adoption strategy was a key determinant of potential impact. “If assumptions of antineoplastic substitution requiring treatment naïve status were relaxed, costs savings relative to target would go from $1200 per eligible episode to $2700,” they wrote.

Financial Impact of Biosimilars in the OCM

Increased use of biosimilars within the US Oncology Network was found have generated millions of dollars in savings in the OCM, suggesting that continued adoption could increase savings to Medicare in the OCM.²

Under the OCM, practices are rewarded for lowering the total cost of care (TCOC) by utilizing lower-cost medications, including biosimilars. Biosimilar options for Avastin (bevacizumab), Herceptin (trastuzumab), and Rituxan (rituximab) were introduced in the United States in 2019 and 2020, leading to a concerted approach or biosimilar adoption within the US Oncology Network.

Researchers looked at claims data for biosimilar utilization among the 14 US Oncology Network practices participating in the OCM during the OCM performance period 8 (PP8), which enrolled patients from January 2, 2020, to July 1, 2020, to compare the cost of each dose of a biosimilar with the estimated cost if the originator had been used.

The results showed that during PP8, utilization of biosimilars of bevacizumab, trastuzumab, and rituximab increased 43%, 33%, and 41%, respectively. The difference in the TCOC with increased biosimilar utilization vs the estimated cost of prioritizing originators led to a savings of $6.61 million.

The researchers estimated that if the health network increased its adoption of bevacizumab, trastuzumab, and rituximab biosimilars to 100%, it could save nearly 1.5% of the TCOC in the US Oncology Network compared with if it continued use of the reference products at their current percentages.

The results of the analysis come after CMS announced that the OCM will officially end at the end of June 2022 without a replacement, which is expected to create a mountain of issues for oncology practices as they figure out how to get by and make changes without the same payments.

Reference

1. Yang J, Chaudhry BI, Yue A, et al. Projected impact of oncology biosimilar substitution from the perspective of provider risk in value-based oncology payment models. Presented at: ASCO 2022; June 3-7, 2022; Chicago, Illinois. Abstract e18836.

2. Wilfong LS, Indurlal P, Dominguez K, et al. Financial impact of biosimilar adoption in the oncology care model for the U.S. Oncology Network. Presented at: ASCO 2022; June 3-7, 2022; Chicago, Illinois. Abstract e18749.