flutemetamol ((18)F)

Absorption

The time-activity curves for flutemetamol F 18 in the brain of subjects with positive scans shows continual signal increases from time zero through 30 minutes post administration, with stable values thereafter up to at least 120 minutes post-injection. Following intravenous injection of 185 MBq (5 mCi) of Vizamyl in humans, flutemetamol F 18 plasma concentrations declined by approximately 75% in the first 20 minutes post-injection, and by approximately 90% in the first 180 minutes.

Toxicity

Most commonly reported adverse reactions were flushing (2%), headache (1%), increased blood pressure (2%), nausea (1%), and dizziness (1%).

Background

Flutemetamol (18F) is a PET scanning radiopharmaceutical containing the radionuclide fluorine-18. It is indicated for Positron Emission Tomography (PET) imaging of the brain to estimate β amyloid neuritic plaque density in adult patients with cognitive impairment who are being evaluated for Alzheimer's disease (AD) or other causes of cognitive decline.

Indications

Flutemetamol F18 is indicated for Positron Emission Tomography (PET) imaging of the brain to estimate β amyloid neuritic plaque density in adult patients with cognitive impairment who are being evaluated for Alzheimer's disease (AD) or other causes of cognitive decline.

Definition

ChEBI: Flutemetamol ((18)F) is a member of the class of benzothiazoles that is 1,3-benzothiazole substituted by 3-((18)F)fluoro-4-(methylamino)phenyl and hydroxy groups at positions 3 and 6 respectively. A positron emission tomography imaging ligand for the detection of amyloid aggregation associated with Alzheimer disease. It has a role as a radioactive imaging agent. It is a (18)F radiopharmaceutical, a member of benzothiazoles, an aromatic amine and a secondary amino compound.

Pharmacokinetics

Following intravenous injection, flutemetamol F 18 diffuses across the human blood-brain barrier and produces a radioactivity signal detectable throughout the brain. Subsequently, cerebral perfusion decreases the brain flutemetamol F 18 content, with differential retention of the drug in cortical areas that contain β-amyloid aggregates compared to areas that lack the aggregates.

Metabolism

The F 18 in circulation during the 30-120 minutes imaging window in plasma was principally associated with flutemetamol metabolites.