investigational
adjective
in·ves·ti·ga·tion·al in-ˌve-stə-ˈgā-sh(ə-)nəl 
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
Example Sentences
Recent Examples on the Web 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 The investigational compound is the first such medicine to deliver more than 20% weight loss on average, compared to placebo, in a Phase 3 study. Joshua Cohen, Forbes, 1 May 2022 The vaccine uses the immune modulator Protollin, an investigational intranasal agent that stimulates the immune system. Julia Musto, Fox News, 16 Nov. 2021 In a new study released today from COTA, an oncology data firm, two-thirds (66%) of cancer patients and close family members surveyed reported feeling disappointed or frustrated with the pace of investigational cancer treatment. Deb Gordon, Forbes, 31 Aug. 2021 See More
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 The investigational compound is the first such medicine to deliver more than 20% weight loss on average, compared to placebo, in a Phase 3 study. Joshua Cohen, Forbes, 1 May 2022 The vaccine uses the immune modulator Protollin, an investigational intranasal agent that stimulates the immune system. Julia Musto, Fox News, 16 Nov. 2021 In a new study released today from COTA, an oncology data firm, two-thirds (66%) of cancer patients and close family members surveyed reported feeling disappointed or frustrated with the pace of investigational cancer treatment. Deb Gordon, Forbes, 31 Aug. 2021 See More Word History
First Known Use
1905, in the meaning defined at sense 1