bio·​sim·​i·​lar | \ -ˈsi-mə-lər, -ˈsim-lər How to pronounce biosimilar (audio) \

Medical Definition of biosimilar

: 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, 4 Aug. 2011

Other Words from biosimilar

biosimilar adjective
biosimilar drugs
biosimilarity \ -​ˌsi-​mə-​ˈler-​ə-​tē How to pronounce biosimilar (audio) \ 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), 28 June 2007

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Cite this Entry

“Biosimilar.” Medical Dictionary, Merriam-Webster, Accessed 6 Dec. 2021.

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