bio·​sim·​i·​lar -ˈsi-mə-lər, -ˈsim-lər How to pronounce biosimilar (audio)
: a substance of biological origin (such as a globulin, vaccine, or hormone) that is used in the prevention or treatment of disease and is highly similar to a previously-approved proprietary biologic

Note: Biosimilars must be found to have no clinically significant difference to the previously-approved biologic and only vary in their clinically inactive components.

Under the BPCI Act, biosimilars will also have the opportunity to meet a higher standard of similarity to a reference product—"interchangeability," reflecting an FDA assessment that pharmacists can make substitutions between biologics without the prescriber's intervention.Steven Kozlowski et al., The New England Journal of Medicine
biosimilar adjective
biosimilar drugs
biosimilarity noun
A demonstration of biosimilarity will have to include analytical data, animal testing and one or more clinical studies, unless such a requirement is determined by the FDA to be unnecessary. Robert Cohen, The Star-Ledger (Newark, New Jersey)

Dictionary Entries Near biosimilar

Cite this Entry

“Biosimilar.” Medical Dictionary, Merriam-Webster, Accessed 31 Mar. 2023.

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