open-label

adjective

open-la·​bel ˌō-pən-ˈlā-bəl How to pronounce open-label (audio)
: being or relating to a clinical trial in which the treatment given to each subject is not concealed from either the researchers or the subject
an open-label multicenter study
compare double-blind, single-blind

Examples of open-label in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Why a Learned Response May Explain the Relief Mills and his team suggest the open-label placebo effect may be rooted in years of conditioning. Samantha Agate, Miami Herald, 12 June 2026 The scientific evidence behind the drug so far consists mostly of small observational studies and open-label trials. Kerry Breen, CBS News, 18 Apr. 2026 Two weeks later, everybody involved in the study got an open-label dose. ArsTechnica, 18 Feb. 2026 Earlier this year, the company launched an open-label clinical trial at Sydney’s Mater Hospital and announced the successful dosing of its first patient. Heather Farmbrough, Forbes.com, 1 Jan. 2026 Psilocybin with psychological support for treatment-resistant depression: An open-label feasibility study. Josh Hammer, MSNBC Newsweek, 21 Apr. 2025 The company is conducting an open-label extension trial to assess the long-term safety and efficacy of brilaroxazine in patients with stable schizophrenia. Quartz Intelligence Newsroom, Quartz, 3 Apr. 2025 So far, the growing body of study into open-label placebos has revealed positive effects in patients with back pain, nausea, IBS and migraine. New Atlas, 22 Feb. 2025 Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Matt Rozo, The Mercury News, 6 Jan. 2025

Word History

First Known Use

1979, in the meaning defined above

Time Traveler
The first known use of open-label was in 1979

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Cite this Entry

“Open-label.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/open-label. Accessed 18 Jun. 2026.

Medical Definition

open-label

adjective
: being or relating to a clinical trial in which the treatment given to each subject is not concealed from either the researchers or the subject
long-term open-label studies
compare double-blind, single-blind
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