investigational

adjective

in·​ves·​ti·​ga·​tion·​al in-ˌve-stə-ˈgā-sh(ə-)nəl How to pronounce investigational (audio)
1
: of or relating to investigation
investigational activities
2
: relating to or being a drug or medical procedure that is not approved for general use but is under investigation in clinical trials regarding its safety and efficacy
an investigational new drug

Examples of investigational in a Sentence

Recent Examples on the Web
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An investigational therapy from Alnylam Pharmaceuticals did not meet its primary goal of significantly lowering blood pressure in a new phase 2 study, raising questions about its benefit. Amy Feldman, Forbes.com, 3 Sep. 2025 While still taking their regular medication, study patients receive monthly injections of an investigational drug that slows production of the surface antigen, the hallmark of the infection. Jia H. Jung, Mercury News, 1 Sep. 2025 Recently, an investigational brain-computer interface system developed by the University of California, Davis, has allowed a patient with ALS to communicate in real time. Mrigakshi Dixit, Interesting Engineering, 1 Sep. 2025 Schmid worries their absence could impact the implementation of a new investigational PrEP medication that, if approved, would only need to be administered twice a year. Joseph Choi, The Hill, 15 Apr. 2025 See All Example Sentences for investigational

Word History

First Known Use

1905, in the meaning defined at sense 1

Time Traveler
The first known use of investigational was in 1905

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Cite this Entry

“Investigational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/investigational. Accessed 11 Sep. 2025.

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