Flortaucipir (¹⁸F), sold under the brand name Tauvid, is a radioactive diagnostic agent indicated for use with

positron emission tomography Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, r ...

(PET)

imaging Imaging is the representation or reproduction of an object's form; especially a visual representation (i.e., the formation of an image). Imaging technology is the application of materials and methods to create, preserve, or duplicate images. ...

to image the brain. The most common adverse reactions include headache, injection site pain and increased blood pressure. Two proteins – tau and

amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of typically 7–13 nm in diameter, a β-sheet secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human ...

– are recognized as hallmarks of

Alzheimer's disease Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...

. In people with Alzheimer's disease, pathological forms of

tau protein The tau proteins (abbreviated from tubulin associated unit) form a group of six highly soluble protein isoforms produced by alternative splicing from the gene ''MAPT'' (microtubule-associated protein tau). They have roles primarily in maintainin ...

s develop inside neurons in the brain, creating

neurofibrillary tangle Neurofibrillary tangles (NFTs) are intracellular aggregates of hyperphosphorylated tau protein that are most commonly known as a primary Biomarker (medicine), biomarker of Alzheimer's disease. Their presence is also found in numerous other disea ...

s. After flortaucipir (¹⁸F) is administered intravenously, it binds to sites in the brain associated with this tau protein misfolding. The brain can then be imaged with a PET scan to help identify the presence of tau pathology. It is the first drug used to help image a distinctive characteristic of Alzheimer's disease in the brain called tau pathology. The US

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respo ...

(FDA) considers it to be a

first-in-class medication A first-in-class medication is a prototype drug that uses a "new and unique mechanism of action" to treat a particular medical condition. While the Food and Drug Administration's Center for Drug Evaluation and Research tracks first-in-class medic ...

Medical uses

Flortaucipir (¹⁸F) is a radioactive diagnostic agent for adults with cognitive impairment who are being evaluated for Alzheimer's disease. 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. Flortaucipir (¹⁸F) is not indicated for use in the evaluation of people for chronic traumatic encephalopathy (CTE).

Chemistry

Chemically, flortaucipir F 18 is 7-(6- -18luoropyridin-3-yl)-5H-pyrido ,3 bndole.

History

Flortaucipir (aka ¹⁸F-T807) was discovered by the Siemens biomarker research group, headed by Hartmuth Kolb and Katrin Szardenings, who also conducted first in human trials. Flortaucipir (¹⁸F) was approved for medical use in the United States in May 2020. The safety and effectiveness of flortaucipir (¹⁸F) imaging was evaluated in two clinical studies. In each study, five evaluators read and interpreted the flortaucipir (¹⁸F) imaging. The evaluators were blinded to clinical information and interpreted the imaging as positive or negative. 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. 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. 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. 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). The study gauged how well flortaucipir (¹⁸F) evaluators' readings agreed with each other's assessments of the readings. Perfect reader agreement would be 1, while no reader agreement would be 0. In this study, reader agreement was 0.87 across all 241 participants. 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. The US

(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. 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.

Society and culture

Legal status

The US

(FDA) granted the application for flortaucipir (¹⁸F)

priority review Priority review is a program of the United States Food and Drug Administration (FDA) to expedite the review process for drugs that are expected to have a particularly great impact on the treatment of a disease. The priority review voucher program ...

and it granted approval of Tauvid to Avid Radiopharmaceuticals, Inc. In June 2024, the

Committee for Medicinal Products for Human Use The Committee for Medicinal Products for Human Use (CHMP), formerly known as the Committee for Proprietary Medicinal Products (CPMP), is the European Medicines Agency's committee responsible for elaborating the agency's opinions on all issues regar ...

(CHMP) of the

European Medicines Agency The European Medicines Agency (EMA) is an agency of the European Union (EU) in charge of the evaluation and supervision of pharmaceutical products. Prior to 2004, it was known as the European Agency for the Evaluation of Medicinal Products ...

adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Tauvid, intended for the diagnosis of Alzheimer's disease. The applicant for this medicinal product is Eli Lilly Nederland B.V. Text was copied from this source which is copyright European Medicines Agency. Reproduction is authorized provided the source is acknowledged. Flortaucipir (¹⁸F) was approved for medical use in the European Union in August 2024.

Names

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

References

External links

* * * * {{DEFAULTSORT:Flortaucipir F18 Alzheimer's disease Medicinal radiochemistry PET radiotracers Radiopharmaceuticals Disubstituted pyridines