Flortaucipir (18F)

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Flortaucipir (18F)
Flortaucipir.png
Clinical data
Pronunciationflor tau' si pir 18 F
Trade names Tauvid
Other names18F-AV-1451, 18F-AV-1451, 18F-T807, Flortaucipir F-18, flortaucipir F 18 (USAN US)
License data
Routes of
administration
Intravenous
ATC code
Legal status
Legal status
Identifiers
  • 7-(6-(18F)fluoropyridin-3-yl)-5H-pyrido[4,3-b]indole
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEMBL
Chemical and physical data
Formula C16H1018FN3
Molar mass 262.27g·mol−1
3D model (JSmol)
  • C1=CC2=C(C=C1C3=CN=C(C=C3)[18F])NC4=C2C=NC=C4
  • InChI=1S/C16H10FN3/c17-16-4-2-11(8-19-16)10-1-3-12-13-9-18-6-5-14(13)20-15(12)7-10/h1-9,20H/i17-1
  • Key:GETAAWDSFUCLBS-SJPDSGJFSA-N

Flortaucipir (18F), sold under the brand name Tauvid, is a radioactive diagnostic agent indicated for use with positron emission tomography (PET) imaging to image the brain. [2] [1] [3]

Contents

The most common adverse reactions include headache, injection site pain and increased blood pressure. [2] [1]

Two proteins – tau and amyloid – are recognized as hallmarks of Alzheimer's disease. [2] In people with Alzheimer's disease, pathological forms of tau proteins develop inside neurons in the brain, creating neurofibrillary tangles. [2] After flortaucipir (18F) is administered intravenously, it binds to sites in the brain associated with this tau protein misfolding. [2] The brain can then be imaged with a PET scan to help identify the presence of tau pathology. [2]

It is the first drug used to help image a distinctive characteristic of Alzheimer's disease in the brain called tau pathology. [2] The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. [4]

Medical uses

Flortaucipir (18F) is a radioactive diagnostic agent for adults with cognitive impairment who are being evaluated for Alzheimer's disease. [1] It is indicated for positron emission tomography (PET) imaging of the brain to estimate the density and distribution of aggregated tau neurofibrillary tangles (NFTs), a primary marker of Alzheimer's disease. [2] [1] [3]

Flortaucipir (18F) is not indicated for use in the evaluation of people for chronic traumatic encephalopathy (CTE). [2] [1]

Chemistry

Chemically, flortaucipir F 18 is 7-(6-[F-18]fluoropyridin-3-yl)-5H-pyrido[4,3 b]indole. [1]

History

Flortaucipir (aka 18F-T807) was discovered by the Siemens biomarker research group, headed by Hartmuth Kolb and Katrin Szardenings, [5] who also conducted first in human trials. [6] Flortaucipir (18F) was approved for medical use in the United States in May 2020. [2] [7] [8]

The safety and effectiveness of flortaucipir (18F) imaging was evaluated in two clinical studies. [2] In each study, five evaluators read and interpreted the flortaucipir (18F) imaging. [2] The evaluators were blinded to clinical information and interpreted the imaging as positive or negative. [2]

The first study enrolled 156 participants who were terminally ill and agreed to undergo flortaucipir (18F) imaging and participate in a post-mortem brain donation program. [2] In 64 of the participants who died within nine months of the flortaucipir (18F) brain scan, evaluators' reading of the flortaucipir (18F) scan was compared to post-mortem readings from independent pathologists who evaluated the density and distribution of neurofibrillary tangles (NFTs) in the same brain. [2] The study showed evaluators reading the flortaucipir (18F) images had a high probability of correctly evaluating participants with tau pathology and had an average-to-high probability of correctly evaluating participants without tau pathology. [2]

The second study included the same participants with terminal illness as the first study, plus 18 additional participants with terminal illness, and 159 participants with cognitive impairment being evaluated for Alzheimer's disease (the indicated patient population). [2] The study gauged how well flortaucipir (18F) evaluators' readings agreed with each other's assessments of the readings. [2] Perfect reader agreement would be 1, while no reader agreement would be 0. [2] In this study, reader agreement was 0.87 across all 241 participants. [2] In a separate subgroup analysis that included the 82 terminally ill participants diagnosed after death and the 159 participants with cognitive impairment, reader agreement was 0.90 for the participants in the indicated population and 0.82 in the terminally ill participants. [2]

The FDA approved flortaucipir (18F) based on evidence of 1921 participants from 19 trials conducted at 322 sites in the United States, Australia, Belgium, Canada, France, Japan, Netherlands and Poland. [3]

The ability of flortaucipir (18F) to detect tau pathology was assessed in participants with generally severe stages of dementia and may be lower in participants in earlier stages of cognitive decline than in the participants with terminal illness who were studied. [2]

The U.S. Food and Drug Administration (FDA) granted the application for flortaucipir (18F) priority review and it granted approval of Tauvid to Avid Radiopharmaceuticals, Inc. [2]

Names

Flortaucipir (18F) is the international nonproprietary name (INN). [9]

Related Research Articles

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References

  1. 1 2 3 4 5 6 7 "Tauvid- flortaucipir f-18 injection, solution". DailyMed. 22 July 2020. Retrieved 28 May 2022.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 "FDA Approves First Drug to Image Tau Pathology in Patients Being Evaluated for Alzheimer's Disease". U.S. Food and Drug Administration (FDA) (Press release). 28 May 2020. Retrieved 28 May 2020.PD-icon.svg This article incorporates text from this source, which is in the public domain .
  3. 1 2 3 "Drug Trial Snapshot: Tauvid". U.S. Food and Drug Administration (FDA). 28 May 2020. Retrieved 10 June 2020.PD-icon.svg This article incorporates text from this source, which is in the public domain .
  4. "New Drug Therapy Approvals 2020". U.S. Food and Drug Administration (FDA). 31 December 2020. Retrieved 17 January 2021.PD-icon.svg This article incorporates text from this source, which is in the public domain .
  5. Xia CF, Arteaga J, Chen G, Gangadharmath U, Gomez LF, Kasi D, et al. (November 2013). "[(18)F]T807, a novel tau positron emission tomography imaging agent for Alzheimer's disease". Alzheimer's & Dementia. 9 (6): 666–676. doi:10.1016/j.jalz.2012.11.008. PMID   23411393. S2CID   1079628.
  6. Chien DT, Bahri S, Szardenings AK, Walsh JC, Mu F, Su MY, et al. (20 June 2013). "Early clinical PET imaging results with the novel PHF-tau radioligand [F-18]-T807" (PDF). Journal of Alzheimer's Disease. 34 (2): 457–468. doi:10.3233/JAD-122059. PMID   23234879. S2CID   46044539.
  7. "Lilly Receives U.S. FDA Approval of Tauvid (flortaucipir F 18 injection) for Use in Patients Being Evaluated for Alzheimer's Disease" (Press release). Eli Lilly. 28 May 2020. Retrieved 28 May 2020 via PR Newswire.
  8. "Drug Approval Package: Tauvid". U.S. Food and Drug Administration (FDA). 16 July 2020. Retrieved 28 May 2022.
  9. World Health Organization (2016). "International nonproprietary names for pharmaceutical substances (INN): recommended INN: list 76". WHO Drug Information. 30 (3). hdl: 10665/331020 .

Further reading