Characterization of Cerebral Tau Aggregates With 18F-RO6958948 PET in the ALFA Population

CROSS-SECTIONAL OBJECTIVES

• To measure 18F-RO6958948 retention in selected participants of ALFA-related studies as a function of amyloid levels.
• To study the relation between 18F-RO6958948 retention and amyloid levels.
• To characterize imaging correlates as a function of tau and amyloid levels.
• To study the role of tau retention on cognitive performance.
• To define predictors of tau retention.

LONGITUDINAL OBJECTIVES

• To measure tau accumulation and spreading in participants of the ALFA-related studies of BBRC as a function of baseline amyloid levels.
• To study the dynamic relation between tau spreading and amyloid levels longitudinally.
• To define predictors of tau spreading.

Inclusion criteria

• To sign the study informed consent form approved by the corresponding authorities.
• Men and women that have participated in a BBRC-sponsored study, including the ALFA project (STUDY 45-65 FPM/2012), the ALFA+ cohort study (ALFA - FPM - 0311), the ALFA cognition study (ALFAcognition/BBRC2017) or the BarcelonaBeta Dementia Prevention Research Clinic study (BBRC-DemPrev-2018).
• Participants with an available cerebral MRI within the last 12 months not suggestive of radiological incidental findings constituting an exclusion criterion.
• Known cognitive status based on the cognitive workup of the BBRC-sponsored studies specified above. Cognitive status should have been determined within the last 12 months.
• Known AB and tau status.
• Good knowledge of the language and being literate.
• Female participants should be post-menopausal or present a negative pregnancy test at the moment of PET acquisition.

Exclusion criteria

• Presence of clinically relevant psychiatric disorder according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-V) criteria: major depressive disorder, generalized anxiety disorder, schizophrenia and bipolar disorder, as assessed in the BBRC-sponsored studies specified above.
• Participants with visual and/or hearing impairment.
• History of encephalitis, ictus or seizures excluding feverish convulsions during childhood, as assessed in the BBRC-sponsored studies specified above.
• Severe cerebral macrovascular (i.e., multi-stroke) disease or brain tumour (metastasis/brain cancer) as verified by MRI.
• Previous participation in a clinical study involving an investigational pharmaceutical product within 30 days prior to screening and/or administration of a radiopharmaceutical within 10 radioactive half-lives prior to study drug administration in this study.
• Clinically relevant renal or hepatic insufficiency.
• Any other clinically important condition that may jeopardize the study or be dangerous for the participant.
• Active drug or alcohol abuse, as assessed in the BBRC-sponsored studies specified above.
• Previous intolerance to PET studies or known hypersensitivity to 18F-RO6958948.
• Being pregnant or breast-feeding.