Medical Dictionary


noun bio·sim·i·lar \-ˈsi-mə-lər, -ˈsim-lər\

Medical Definition of biosimilar

  1. :  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 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


adjective biosimilar drugs


\-ˌsi-mə-ˈler-ə-tē\ play 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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a brief usually trivial fact

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