BioRationality: a Dr Sarfaraz Niazi Column—The EMA Declares Biosimilars Interchangeable

Sarfaraz K. Niazi, PhD, explains the significance of the European Medicines Agency (EMA) declaring that biosimilars are interchangeable with their reference products and calls for the United States to do the same in the first installment of his new monthly column.

While the US maintains a special interchangeable status for biosimilars, the European Medicines Agency (EMA) had left the decisions to the member states until this week, as it released its new guidance[1] that makes biosimilars interchangeable with their reference products. I had the privilege of submitting a detailed analysis of why biosimilars should be interchangeable without requiring additional studies, switching, and alternating, as needed in the United States. This report was also published recently.[2] The focus of this publication was to convince the US Congress and the US FDA to remove the interchangeable status, as it adds to uncertainty about biosimilars. The concurrence by EMA is a game-changer as it will bring high confidence among the stakeholders who may be unsure about the safety and efficacy of biosimilars. Another publication recently concluded that interchanging from one biosimilar to another biosimilar is safe and effective.[3] This should not have been unexpected based on Plato's principle of equality that if A=B and C=A, then B=C.[4]

While interchangeability is a legislative issue in the United States as described in the Biologics Price Competition and Innovation Act (BPCIA),[5] where an approved biosimilar product is further tested using switching and interchanging to qualify the interchangeable status. The FDA can do little to remove the interchangeability, but they can award an interchangeable status without requiring the 3 cycles of switching and alternating, as they have recently done in granting such status to Cimerli, a ranibizumab biosimilar developed by Coherus Biosciences.

While this status provides a distinction to the product, it has little value since ranibizumab is not self-administered and is thus not subject to substitution. In many ways, awarding an interchangeable status based on the same data that would have resulted in the licensing as a biosimilar has done more harm—the race to get the interchangeable status for marketing purposes if there are other biosimilars available that cannot be interchangeable. In the United States, the bar will move only after amendments are made to the BPCIA, and Senators like Ben Ray Luján (D-New Mexico) are pushing for this.[6]

The giant leap that the EMA has taken comes from the simple understanding, as written by the FDA, that a biosimilar is approved with a label of having "no clinically meaningful difference with the reference product."[7] Why would switching with the reference product will make any difference? The testing studies go farther requiring multiple switching and alternating that makes little sense. None of these studies have ever failed because they cannot be based on statistical and experimental design.

Biosimilars are used interchangeably across the globe, except in the United States. It is time that Senators wake up to it and amend the BPCIA.


[1] Biosimilar medicines can be interchanges. EMA website. September 19, 2022. Accessed October 3, 2022.

[2]Niazi SK. No two classes of biosimilars: urgent advice to the US Congress and the FDA. J Clin Pharm Ther. Published July 22, 2022. Accessed October 3, 2022. doi: 10.1111/jcpt.13743

[3] Cohen HP, Hachaichi S, Bodenmueller W, et al. Switching from one biosimilar to another biosimilar of the same reference biologic: a systematic review of studies. BioDrugs. 2022;36(5):625-637. doi: 10.1007/s40259-022-00546-6

[4] Equality. Stanford Encyclopedia of Philosophy. March 27, 2001. Updated April 26, 2021. Accessed October 3, 2022.

[5] H.R.3590 Patient Protection and Affordable Care Act. FDA. Accessed October 3, 2922.

[6] Luján Introduces Legislation to Reduce Animal Testing. Senator Ben Ray Luján’s website. May 20, 2022. Accessed October 3, 2022.

[7] Biosimilar and interchangeable products. FDA website. Updated October 23, 2017. Accessed October 3, 2022.