Flortaucipir (18F)

Flortaucipir (18F) Uses, Dosage, Side Effects, Food Interaction and all others data.

Flortaucipir (18F), also known as F-T807 and F-AV-1451, is a small indole molecule synthesized with a radioactive fluorine isotope. It is used as a marker in positron emission tomography (PET) imaging of patients suspected of having Alzheimer's disease. After crossing the blood-brain barrier, flortaucipir F-18 binds to aggregated tau protein, a hallmark of Alzheimer's disease whose incidence correlates well with disease progression.

Although flortaucipir F-18 displays low levels of background binding throughout the brain, it does display off-target binding to monoamine oxidase MAO-A and MAO-B, as well as to regions containing high levels of melanin, neuromelanin, and iron. It is the first FDA-approved molecule for imaging aggregated tau protein in the brain.

Flortaucipir (18F) is a radioactive molecule that binds to and accumulates in tau NFT deposits allowing for imaging detection; however, non-specific binding and other factors allow for the possibility of misdiagnosis. As Flortaucipir (18F) is a radioactive substance, standard precautionary measures for protecting both patients and health care workers are advised. The safety and efficacy of flortaucipir F-18 in patients being evaluated for chronic traumatic encephalopathy are unknown and hence is not recommended.

Flortaucipir (18F)
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Flortaucipir (18F)
Generic	Flortaucipir F-18
Flortaucipir F-18 Other Names	Flortaucipir (18F), Flortaucipir F 18
Type
Formula	C₁₆H₁₀FN₃
Weight	Average: 262.278 Monoisotopic: 262.088410001
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country
Last Updated:	September 19, 2023 at 7:00 am

Uses

Flortaucipir (18F) is a small lipophilic tracer containing [18F]fluoride capable of crossing the blood-brain barrier and binding to aggregated tau protein; used in PET imaging for the diagnosis of Alzheimer's disease.

Flortaucipir (18F) is a radioactive agent indicated for positron emission tomography (PET) imaging of aggregated tau neurofibrillary tangles (NFTs) in adult patients under evaluation for Alzheimer's disease. Flortaucipir (18F) is not indicated for use in patients under evaluation for chronic traumatic encephalopathy.

Flortaucipir (18F) is also used to associated treatment for these conditions: Alzheimer's Disease (AD)

How Flortaucipir (18F) works

Alzheimer's disease is a progressive neurodegenerative disease characterized by the build-up of hyperphosphorylated tau protein aggregates. Hyperphosphorylated tau forms dimers termed paired helical filaments (PHFs), which aggregate further to form neurofibrillary tangles (NFTs) associated with neurodegeneration and severity of Alzheimer's symptoms.

Flortaucipir (18F) is a small molecule that contains radioactive ^{18 As a small relatively lipophilic molecule, flortaucipir F-18, following intravenous injection, quickly passes through systemic circulation, crosses the blood-brain barrier, and binds to NFTs. Once bound, the ensuing radioactive decay emits pairs of 511 keV gamma photons useful in diagnostic imaging. The pattern and intensity of emission during imaging is used in the diagnosis of Alzheimer's disease.}

Toxicity

Toxicity information regarding Flortaucipir (18F) is not readily available. Patients experiencing an overdose are at an increased risk of severe adverse effects such as headaches and increased blood pressure. Symptomatic and supportive measures are recommended.

Food Interaction

No interactions found.

Volume of Distribution

Flortaucipir (18F) injected into mice accumulates primarily in the kidneys (14.99 ± 0.39 %ID/g at five minutes and 5.52 ± 0.91 %ID/g at 30 minutes post-injection) and liver (4.44 ± 0.16/5.99 ± 0.42 %ID/g at five/30 minutes, respectively). It is able to cross the blood-brain barrier, with relatively high penetration early (4.43 ± 0.91 %ID/g at five minutes) and low residual penetration later (0.62 ± 0.06 %ID/g at 30 minutes). Detectable amounts of Flortaucipir (18F) are found in the systemic circulation, as well as in muscle and bone.

Elimination Route

Flortaucipir (18F) is administered as an intravenous bolus injection, and peak brain uptake in mice of 4.16% ID/g is achieved by 2 minutes. Fast transfer from the peripheral circulation to the brain was corroborated by human studies that demonstrated peak SUV in gray matter >2 across subjects approximately 5 minutes after administration.

Pharmacokinetic studies in humans suggest that equilibrium is achieved by 55 minutes (Logan DVR) and by 80 - 100 minutes (SUVR), and current guidelines recommend initiating imaging approximately 80 minutes after initial administration.

Half Life

Flortaucipir (18F) plasma half-life was calculated at 17.0 ± 4.2 minutes; correction for metabolite half-life yielded a biexponential distribution with half-lives of 18.1 ± 5.8 and 2.4 ± 0.5 minutes.