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

Examples of tocilizumab in a Sentence

Recent Examples on the Web The drug tocilizumab is sold as Actemra and RoActemra for rheumatoid arthritis and other diseases. Chronicle Staff,, 22 Sep. 2020 In fact, as of Monday, the FDA has launched Phase III trials of tocilizumab for treating COVID-19 pneumonia. IEEE Spectrum, 25 Mar. 2020 Roche, which makes tocilizumab, did its own tests in COVID patients and reported that its drug was not helpful. Gina Kolata, Star Tribune, 14 Nov. 2020 Those treated with tocilizumab were less likely to need mechanical ventilation by day 28 (12% vs. 19% when compared to standard care). Verywell Health, 27 Jan. 2023 At the start of the Covid pandemic, researchers offered all sorts of theories about medicines — hydroxychloroquine, ivermectin, and tocilizumab among them — that might help to treat Covid. Matthew Herper, STAT, 3 Nov. 2022 In the same way, pregnant patients’ biological ages were restored during postpartum recovery, and patients recovering from COVID-19 had their biological age enhanced after using the immunosuppressive drug tocilizumab. L'oreal Thompson Payton, Fortune Well, 21 Apr. 2023 Dexamethasone, a cheap and common steroid, surprised doctors by slicing mortality in the sickest patients in a randomized trial; another anti-inflammatory, tocilizumab, also helped patients survive. Kelly Servick, Science | AAAS, 16 Mar. 2021 The drug in question, tocilizumab, was being investigated as a potential treatment for coronavirus patients who experienced high levels of inflammation. Rachael Zisk, Popular Science, 26 Oct. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'tocilizumab.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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.

First Known Use

2004, in the meaning defined above

Time Traveler
The first known use of tocilizumab was in 2004

Dictionary Entries Near tocilizumab

Cite this Entry

“Tocilizumab.” Dictionary, Merriam-Webster, Accessed 12 Apr. 2024.

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