to·​ci·​liz·​u·​mab | \ ˌtō-sə-ˈli-zü-ˌmab How to pronounce tocilizumab (audio) \

Definition of tocilizumab

: an immunosuppressive drug that is a monoclonal antibody which binds to cell receptors and blocks the action of interleukin-6 and that is administered by injection to treat various inflammatory conditions (such as rheumatoid arthritis) Tocilizumab specifically blocks the action of the inflammatory protein interleukin-6, which shows up in excessive amounts in joints of rheumatoid arthritis patients.— Nathan Seppa

First Known Use of tocilizumab

2004, in the meaning defined above

History and Etymology for tocilizumab

tocili- (of undetermined origin) + -zu-, prefix denoting humanized antibodies (antibodies from non-human species with protein sequences modified to increase similarity to human antibodies) (probably from letters in humanize) + -mab, combining element denoting a monoclonal antibody

Note: According to the prescriptions of the U.S. Adopted Names Council, the initial element in generic drug names is to be meaningless.

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The first known use of tocilizumab was in 2004

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Last Updated

27 Apr 2020

Cite this Entry

“Tocilizumab.” Dictionary, Merriam-Webster, Accessed 27 May. 2020.

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