in·​ves·​ti·​ga·​tion·​al | \ in-ˌve-stə-ˈgā-shnəl How to pronounce investigational (audio) , -shə-nᵊl \

Definition of investigational

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 July 7, 2020 - Scientists presenting at the 23rd International AIDS Conference announce a new study that found an injection of the investigational drug cabotegravir every eight weeks was more effective at preventing HIV than daily oral pills. Cnn Editorial Research, CNN, 6 June 2021 RedHill Biopharma is testing two investigational oral pills to treat COVID-19. Julie Washington, cleveland, 3 June 2021 About 4,600 children are participating in trials nationwide to evaluate the investigational vaccine BNT162b2, one of the vaccine candidates in development by Pfizer and BioNTech which are also sponsors of the study, Kaiser said. Chronicle Staff, San Francisco Chronicle, 13 June 2021 The company never published results from any formal studies, and Autor claims the company did not have the time or money to conduct a formal research study, called an investigational new drug study, according to FDA standards., 12 June 2021 The decline came after the company decided to pause its early stage clinical trials for AROENaC1001, the company’s investigational treatment for cystic fibrosis. Trefis Team, Forbes, 29 Oct. 2020 The investigational drug worked where other approaches had failed, Dr. Sartor emphasized. New York Times, 24 June 2021 The agency gave stem cell businesses until May 2021 to comply with FDA regulations by either obtaining approval for their products or by submitting an investigational new drug application to start a clinical trial., 11 June 2021 Despite a variety of legal maneuvers, the investigational status of the government’s anthrax vaccine assured that no service members could be required to take it against their will. Melissa Healy, Los Angeles Times, 13 Apr. 2021

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.

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First Known Use of investigational

1905, in the meaning defined at sense 1

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The first known use of investigational was in 1905

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Statistics for investigational

Last Updated

23 Jul 2021

Cite this Entry

“Investigational.” Dictionary, Merriam-Webster, Accessed 26 Jul. 2021.

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