First-in-Human Study for the Safety and Evaluation of Two 4R Tau Ligands as Potential PET Radioligands for Imaging Tau Protein in the Brain

NCT07348276 | Recruiting Early Phase 1 FDA Drug

• 1 other identifier: EPAA-2024-TR01
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

This clinical study is being conducted to learn more about two new imaging drugs, called \[18F\]ABBV-964i and \[18F\]ABBV-965i, which are designed to help doctors see changes in the brain related to a condition called Progressive Supranuclear Palsy (PSP). PSP is a rare disease that affects movement, balance, and thinking. These drugs are used with a type of scan called PET (Positron Emission Tomography) to show areas of the brain where a protein called tau builds up. Tau buildup is linked to PSP and other brain diseases. The main goal of this study is to find out if these imaging drugs are safe for people and if they work well to show tau in the brain. The study will also look at how the drugs move through the body and how much radiation they give off. Researchers hope this information will help develop better tools for diagnosing PSP and tracking how it changes over time. Who can join? Adults who are healthy or who have PSP may be able to take part. Participants will have screening tests to make sure they qualify. What does participation involve? People in the study will have PET scans, blood tests, and other safety checks. Some participants will also have an MRI scan. The study is divided into three parts: Part A checks radiation levels in healthy volunteers, Part B looks at how the drugs work in the brain of PSP patients and healthy volunteers, and Part C (optional) repeats scans to see if results are consistent. Why is this important? There is currently no cure for PSP, and better imaging tools could help researchers develop new treatments. By joining this study, participants will help advance research that may improve care for people with PSP and similar conditions in the future.

Conditions

Healthy Participants; Progressive Supranuclear Palsy (PSP)

Keywords

Tauopathy; Tau; PET Imaging; ABBV-965i; ABBV-964i; PSP; Progressive Supranuclear Palsy

Outcome Measures

Primary Outcomes (2)

• Safety of [18F]ABBV-964i and [18F]ABBV-965i: Incidence of Adverse Events

  Incidence of adverse events (AEs) following administration of \[18F\]ABBV-964i and \[18F\]ABBV-965i.

  Up to 13 weeks

• Radiation dosimetry of [18F]ABBV-964i and [18F]ABBV-965i

  Radiation absorbed dose estimates following administration of \[18F\]ABBV-964i and \[18F\]ABBV-965i, derived from PET imaging and dosimetry calculations.

  Up to 13 weeks

Secondary Outcomes (2)

• Brain Uptake measured as Standardized Uptake Value (SUV) or equivalent

  Up to 13 weeks

• Model-derived Pharmacokinetics parameters

  Up to 13 weeks

Study Arms (3)

Part A - Dosimetry

EXPERIMENTAL

Healthy participants receive \[18F\]ABBV-964i and \[18F\]ABBV-965i for PET imaging.

Drug: [18F]ABBV-964i; Drug: [18F]ABBV-965i

Part B - Proof of Concept

EXPERIMENTAL

Participants receive \[18F\]ABBV-964i and \[18F\]ABBV-965i for PET imaging to see how the drugs work in the brain.

Drug: [18F]ABBV-964i; Drug: [18F]ABBV-965i

Part C - Test-Retest (Optional)

EXPERIMENTAL

Participants receive two PET scans using the same drug to see if results are consistent.

Drug: Lead Candidate

Interventions

[18F]ABBV-964i DRUG

PET radiopharmaceuticals selective for tau, administered intravenously at doses up to 10 mCi.

Part A - Dosimetry; Part B - Proof of Concept

[18F]ABBV-965i DRUG

PET radiopharmaceuticals selective for tau, administered intravenously at doses up to 10 mCi.

Part A - Dosimetry; Part B - Proof of Concept

Lead Candidate DRUG

Preferred PET radiopharmaceuticals (between \[18F\]ABBV-964i and \[18F\]ABBV-965i) selective for tau, administered intravenously at doses up to 10 mCi.

Also known as: [18F]ABBV-965i, [18F]ABBV-964i

Part C - Test-Retest (Optional)

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Males or females: PSP 40-80 years; HV 18-80 years
• Body weight: 43-120 kg (95-265 lb)
• Women of childbearing potential: abstinent or use 2 contraception methods (one barrier) during study and 30 days post last injection
• Men: use 2 contraception methods and refrain from sperm donation during study and 90 days post last injection
• Adequate circulation and normal clotting for arterial cannulation
• Sufficient mobility and ability to lie still for imaging
• Healthy Volunteers: informed consent, no clinically relevant findings, no cognitive impairment
• PSP Participants: informed consent or assent with LAR consent, clinical diagnosis per NINDS-SPSP criteria, MRI consistent with PSP, able to ambulate, tolerate MRI, comply with study procedures, caregiver available if needed

You may not qualify if:

• History of drug or alcohol abuse in past 12 months
• Clinically significant lab abnormalities or unstable illness
• Investigational drug/device use within 30 days
• Pregnant, lactating, or breastfeeding
• Significant comorbid conditions (GI, CV, hepatic, renal, etc.)
• Abnormal clotting parameters (if arterial sampling)
• MRI contraindications (implants, claustrophobia) for PSP participants
• Use of OTC meds or supplements within 2 weeks (healthy volunteers)
• Use of anti-hemostasis meds within 2 weeks of arterial line placement for PSP participants
• Unable to lie still for 90 minutes
• Major surgery or significant blood loss within 4 weeks
• Positive for Hepatitis B, Hepatitis C, or HIV
• Deemed unsuitable by Investigator

Sponsors & Collaborators

• Invicro: lead
• Enigma Biomedical USA: collaborator

Study Sites (1)

Invicro (dba Perceptive)

New Haven, Connecticut, 06510, United States

RECRUITING

MeSH Terms

Conditions

Supranuclear Palsy, Progressive; Tauopathies; Pick Disease of the Brain

Condition Hierarchy (Ancestors)

Basal Ganglia Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Movement Disorders; Ophthalmoplegia; Ocular Motility Disorders; Cranial Nerve Diseases; Neurodegenerative Diseases; Paralysis; Neurologic Manifestations; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Frontotemporal Dementia; Frontotemporal Lobar Degeneration; Dementia; Neurocognitive Disorders; Mental Disorders

Central Study Contacts

David Russell, MD, PhD

CONTACT

203-401-4300; learnmore@perceptive.com

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SEQUENTIAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 26, 2025
• First Posted: January 16, 2026
• Study Start: November 17, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): March 1, 2027
• Last Updated: January 16, 2026

Record last verified: 2026-01

Locations

US (1)