‘Study with the tau Positron Emission Tomography radiotracer [18F]THK-5351 in patients with different Tauopathies’

Rafael Blesa González and María del Valle Camacho Martí, Hospital Sant Pau-Universitat Autònoma; Ignacio Illán Gala, Jordi Pegueroles Monllau, Jordi Clarimon Echavarría and Estrella Morenas Rodríguez, Instituto de Investigación Biomédica Sant Pau; Frederic Sampedro Santaló, Universidad Autónoma de Barcelona; Susana Fernández González, Bessy Benejam Paul and Sebastián Videla Ces, Fundació Catalana Síndrome de Down (FCSD).

Tauopathies are a heterogeneous group of neurodegenerative disorders characterized by the cerebral deposition of tau protein aggregates. Common tauopathies are sporadic Alzheimer`s disease (AD), Alzheimer?s disease associated with Down syndrome (AD-DS) and some cases of frontotemporal lobar degeneration (FTLD).

Recently, some specific positron emission tomography (PET) tracers for tau aggregates have been developed allowing for the first time the visualization of tau pathology in-vivo. These tracers have drawn enormous attention worldwide since they can improve the diagnosis and better define the prognosis in these conditions. However, tau PET tracers have not been tested in our country and only in a few countries in the world. In this proposal we will test for the first time in Europe the novel PET tracer [18 F]THK-5351 developed by the University of Tohoku (Japan), a compound with higher specificity for Tau aggregates than other tracers.

The main objective of this study is to investigate the patterns of Tau deposition using [18 F]THK-5351 in various clinical syndromes associated with tauopathies and to study its relation with clinical symptoms, patterns of cortical atrophy in magnetic resonance imaging (MRI) and biomarkers in cerebrospinal fluid (CSF). Study subjects: 10 cognitively normal controls, 20 patients with typical AD (10 with prodromal AD and 10 with AD dementia), 20 subjects with Down syndrome (10 without dementia and 10 with dementia) and 30 with different forms of FTLD.

Interventions: Clinical and neuropsychological evaluation and CSF biomarkers (t-Tau, p-Tau). Acquisition of brain MRI with 3D structural sequences and tau PET with [18 F]THK-5351. Analysis with FreeSurfer and SPM softwares. The data derived of this project will provide a unique opportunity to investigate in detail the process of tau aggregation in diverse neurodegenerative diseases. This will allow defining its potential use in the diagnosis and as a surrogate marker of progression