Institute Report
Long-term Market Sustainability for Infused Biosimilars in the U.S.
Foundational Analytics on Emerging Risks to Sustainability
Jan 24, 2024

Report Summary

Biosimilars in the U.S. have begun to fulfill their promise of generating savings for the healthcare system by reducing the cost of biologics. However, many studies and reports have highlighted issues within the current system that can lead to sub-optimal uptake of biosimilars and put the long-term sustainability of biosimilars at risk. Understanding these issues with case studies and examples is critical if biosimilars are to continue playing a crucial role in the overall health system.

This report intends to create a base of foundational analytics to better understand the dynamics of biosimilars. The focus of this report is on infused biosimilars that fall under the buy and bill program in Medicare Part B. In particular, the aim is to understand the key issues that can lead to the sub-optimal functioning of the biosimilars market in the U.S. by analyzing various case studies.

Key findings:


Infliximab commercial comparative formulary status, 2018-2023

Infliximab market share over time

  • The example of infliximab has been noted to potentially highlight a dynamic where rebate walls were one of the reasons that drove the slow uptake.
  • In the initial period, the uptake of biosimilars was extremely limited, with most commercial plans preferring the originator on their formulary. This dynamic has been noted as being driven by rebating, however a lack of transparency around rebating makes it hard to ascertain the exact dynamics that took place.
  • After four years, some of the biosimilars began to achieve improved formulary status on commercial plans and the overall uptake began to increase.
  • Overall, across all biosimilar markets, ASPs generally decline by an average of 50% within the first 12 quarters on market.
  • In the current set-up, biosimilars enter a cycle where they are consistently increasing stakeholder rebate/discounts to remain competitive, which results in regular ASP reductions each quarter.
  • While in the case of several oncology biosimilars the biosimilar manufacturers have managed to gain share, uptake has been slow in the case of infliximab and pegfilgrastim.
  • In the case of infliximab, meaningful uptake took four to five years, and in this period, biosimilar ASPs declined substantially. Biosimilars had to wait several years before achieving meaningful revenue, which then subsequently plateaued due to declining ASPs.
  • Not all biosimilar manufacturers have the financial capacity to wait for this extended period and few may be willing to invest in such a risky environment if this becomes the norm. Additionally, provider incentives to switch to the biosimilar, such as lower biosimilar ASP, reduced in the case of infliximab as the originator ASP converged with the biosimilar ASP.
  • This results in a system where the continued capture of biosimilar share remains relatively slow.

Related solutions

Contact Us