Definition

A radioconjugate composed of the paired helical filament (PHF) tau binding agent flortaucipir, a benzimidazole pyrimidine derivative, conjugated to the radioisotope fluorine F 18, with potential tau positron emission tomography (PET) imaging activity. Upon administration, flortaucipir F-18 targets and binds to PHF-tau in the brain, which allows PET imaging of PHF-tau and analysis of phosphorylated PHF-tau aggregates (neurofibrillary tangles). Increased levels of PHF-tau and neurofibrillary tangles are correlated with the cognitive decline seen in neurodegenerative diseases, such as dementia, Alzheimer disease (AD) and chemotherapy-induced cognitive impairment (CICI).