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 The team then considered using another investigational drug. oregonlive, "A simple cough, a diagnosis of COVID-19 for a Tigard woman and the fight to keep her alive," 8 July 2020 The press release states that the investigational vaccines have been given a nod by the FDA for Phase 2 and Phase 3 trials. Sonia Ramirez, Houston Chronicle, "Houston company seeks volunteers for new COVID-19 vaccine trial," 7 July 2020 Remdesivir is approved to treat Covid-19 in Japan, but is considered an investigational treatment for Covid-19 elsewhere in the world, Gilead noted. John Bonifield, CNN, "More evidence remdesivir helps some coronavirus patients," 1 June 2020 When the press release was issued, results were available for eight volunteers on the question of whether the investigational vaccine had produced neutralizing antibodies to the virus. Robert Kuznia, CNN, "Moderna's coronavirus vaccine announcement set off a frenzy on Wall Street. Now some are calling for an investigation," 1 June 2020 Mandapakala is the principle investigator on COVID-19 convalescent plasma trials for the Northern Kentucky hospital system, which is collaborating with the Mayo Clinic on its investigational program. Terry Demio,, "'It was a gift': St. Elizabeth gives COVID-19 convalescent plasma to 40-plus patients," 1 June 2020 Beth-Ann Coller, the team leader on the Ebola vaccine, said all existing stock of the vaccine is investigational — it was made before the vaccine was licensed. Helen Branswell, Scientific American, "Ebola Vaccine Approved in Europe in Landmark Moment," 12 Nov. 2019 The windfall of pleas began on March 24, when the FDA gave the greenlight to expand convalescent plasma treatments for investigational purposes. Tom Hanson, CBS News, "Desperate families turn to social media in search of convalescent plasma," 18 Apr. 2020 For the past five years, Halo’s formula has been going through the Food and Drug Administration’s investigational new drug application process, where it is identified as ARMS-1. John Futty, USA TODAY, "Antiviral oral spray Halo to undergo testing for prevention of coronavirus infection," 2 Apr. 2020

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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Last Updated

22 Jul 2020

Cite this Entry

“Investigational.” Dictionary, Merriam-Webster, Accessed 10 Aug. 2020.

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