in·​ves·​ti·​ga·​tion·​al in-ˌve-stə-ˈgā-sh(ə-)nəl How to pronounce investigational (audio)
: of or relating to investigation
investigational activities
: 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

Example Sentences

Recent Examples on the Web Before beginning studies, the company applied for an investigational device exemption, which the FDA requires for companies testing potentially dangerous medical devices. Mario Aguilar, STAT, 28 July 2022 As alluded to above, the scope of medical devices to which the premarket guidance will be applied expanded greatly—including investigational devices. Mike Kijewski, Forbes, 16 Aug. 2022 Other versions test the investigational drug in patients who had never taken insulin before, those who have Type 1 diabetes and in other situations designed to probe varying scenarios found in the real world. Paul Sisson, San Diego Union-Tribune, 22 Sep. 2022 The financial and emotional burdens of isolating for weeks are one reason that some physicians have argued to expand access to Tpoxx, an investigational drug that has shown promise in sending lesions into retreat. Emily Alpert Reyes, Los Angeles Times, 12 Sep. 2022 The investigational vaccine was also well-tolerated, with no safety concerns, according to the press release. Morgan Winsor, ABC News, 25 Aug. 2022 Strategic National Stockpile, and the Centers for Disease Control and Prevention requires that health care providers submit an investigational new drug, or IND, application in order to access it for their patients. Tanya Lewis, Scientific American, 29 July 2022 Patients do not pay to participate in trials or for investigational drugs, but may incur costs for transportation, child care, or lose income from not working. Angus Chen, STAT, 8 June 2022 At that time, the drug was still in the investigational phase and not yet approved by the F.D.A. for administration to adult women, let alone minor teenagers. New York Times, 8 June 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'investigational.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1905, in the meaning defined at sense 1

Time Traveler
The first known use of investigational was in 1905

Dictionary Entries Near investigational

Cite this Entry

“Investigational.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2022.

Last Updated: - Updated example sentences
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