A Phase 1 interventional study of 18F-Flortaucipir radiopharmaceutical and 18F-MK-6240 radiopharmaceutical in Alzheimer Disease, sponsored by Tharick Pascoal. Active, not recruiting at 9 sites in 3 countries. Open to participants aged 18 Years to 90 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-08.
Sponsored by Tharick Pascoal · Phase 1, Interventional, and Diagnostic
The purpose of this study is to compare/harmonize cross-sectional and longitudinal tau tangle measurements obtained with the tau PET radiopharmaceuticals Flortaucipir and MK-6240 to elucidate the advantages and caveats of their use in clinical trials/practice and provide parameters to integrate their estimates.
This is a longitudinal, multi-site, non-randomized study in which the participants will undergo Flortaucipir and MK-6240 PET scans at baseline and approximately at 18-month follow-up. At each time point, participants will also have an amyloid-β PET scan, magnetic resonance imaging, detailed cognitive tests, and a blood draw for biomarker quantification. The main objectives of this study are standardizing tau PET tracers' outcomes and comparing their performance.
To accomplish our objectives, the investigators propose the following specific aims:
In Aim 1, investigators will standardize tau PET processing methods, convert the tracers to a common scale, compare associations with amyloid-β, atrophy, and cognition, and compare/harmonize Braak staging assessments between tau tracers using cross-sectional data.
In Aim 2, investigators will ascertain the optimal processing method for longitudinal analysis and compare longitudinal changes in tau accumulation obtained with the tau PET radiopharmaceuticals and their associations with changes in amyloid-β, atrophy, and cognition.
In Exploratory Aim 3, investigators will compare cross-sectional and longitudinal Flortaucipir and MK-6240 estimates with plasma phosphorylated tau concentrations.
This study will produce a benchmark dataset to develop methods for tau PET quantification and harmonization.
3,965 studies on the registry are indexed under Alzheimer Disease; 926 are open to participants now.
This study's enrollment of 822 is above the median of 70 across 3,019 interventional studies indexed under Alzheimer Disease.
Browse Alzheimer Disease studies →This is the only study on the registry with Tharick Pascoal as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
All individuals enrolled into the HEAD study will undergo tau PET, amyloid-β PET, magnetic resonance imaging (MRI), detailed clinical and cognitive assessment, and a blood draw.
Drug: 18F-Flortaucipir radiopharmaceutical · Drug: 18F-MK-6240 radiopharmaceutical · Drug: Amyloid-β radiopharmaceutical (11C-PiB or 18F-Florbetaben or 18F-NAV-4694 or 18F-Flutemetamol)
Flortaucipir is a PET radiopharmaceutical that binds to tau neurofibrillary tangles. Participants will receive a bolus intravenous injection of approximately 10 millicuries of the radiopharmaceutical.
Also known as: 18F-AV-1451, 18F-T807, Tauvid
MK-6240 is a PET radiopharmaceutical that binds to tau neurofibrillary tangles. Participants will receive a bolus intravenous injection of approximately 5 millicuries of the radiopharmaceutical.
The clinical sites will use either PiB, Florbetaben, Flutemetamol, or NAV-4694 as the amyloid-β PET radiopharmaceutical. The amyloid-β PET radiopharmaceutical binds to amyloid-β plaques. Participants will receive a bolus intravenous injection of approximately 15 millicuries of the PiB radiopharmaceutical. Participants will receive a bolus intravenous injection of approximately 8 millicuries of the Florbetaben or NAV-4694 radiopharmaceutical. Participants will receive a bolus intravenous injection of approximately 5 millicuries of the Flutemetamol radiopharmaceutical.
Cross-sectional tau PET uptake values
Compare/harmonize cross-sectional tau deposition measurements (standardized uptake value ratio (SUVR)) obtained with Flortaupicir and MK-6240.
Time frame: 2 years from enrollment
Longitudinal change in tau PET uptake values over 18 months
Compare/harmonize change in tau deposition measurements (standardized uptake value ratio (SUVR)) obtained with Flortaupicir and MK-6240 between baseline and 18-month follow-up assessments.
Time frame: 5 years from enrollment
Associations of tau PET uptake values with amyloid-β PET uptake values
Compare the effect size of the associations of tau deposition measurements (standardized uptake value ratio (SUVR)) obtained with Flortaupicir and MK-6240 with amyloid-β deposition measurements (SUVR).
Time frame: 5 years from enrollment
Associations of tau PET uptake values with measures of cognition
Compare the effect size of the associations of tau deposition measurements (standardized uptake value ratio (SUVR)) obtained with Flortaupicir and MK-6240 with cognitive measures assessed from neuropsychological evaluation.
Time frame: 5 years from enrollment
Associations of tau PET uptake values blood biomarkers
Compare the effect size of the associations of tau deposition measurements (standardized uptake value ratio (SUVR)) obtained with Flortaupicir and MK-6240 with blood-based biomarkers of tau.
Time frame: 5 years from enrollment
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — Data from this research will be shared with other researchers pursuant to the 02/26/2003 "NIH Final Statement on Sharing Research Data". To protect participants' rights and confidentiality, identifiers will be removed from the data before they are shared. The board of PIs has primary oversight of the HEAD study resource sharing plan and will review all issues related to internal and external requests for HEAD data. Raw PET and MR data will be uploaded by clinical sites after acquisitions, whereas processed PET and MR data will be uploaded after completion of the baseline visit and after completion of the 18-month follow-up visit. Demographics, results from cognitive tests, Aβ status, tau Braak staging, and plasma assay results will also be available through the LONI platform.
Time frame: Data from baseline and follow-up assessments will be available for sharing after the completion of the respective study visits.
Access criteria: Researchers will be able to download data upon request to the PIs. Data sharing requests will be overseen by the study and site PIs.
Data sharing details ↗ · www.loni.usc.edu
Started Mar 2022 (actual). Primary completion is estimated for May 2027, 62 months after the start.
Of 73 non-industry phase 1 interventional studies under Alzheimer Disease, half reached primary completion within 44 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 57. This study's planned 62 months is above that.
Counting every sponsor, half of 233 studies reached it within 18 months; a quarter within 7 and three quarters within 39.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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