PET Imaging of Noradrenergic Transmission in the Brain

Background:

Researchers have developed a new radioactive tracer (11C-ARMI). A tracer is a drug that attaches itself to other chemicals in the body and lights up so that the chemicals can be seen in imaging scans. The new tracer may be able to help them with many diseases, such as Alzheimer s disease and Parkinson s disease. Researchers want to test the new tracer in healthy people.

Objective:

To test a new tracer (11C-ARMI) during imaging scans of the brain and body in healthy people.

Eligibility:

Healthy people aged 18 years and older. They must have been screened under protocols 01-M-0254 or 17M0181.

Design:

All participants will have a positron emission tomography (PET)/computed tomography (CT) scan. Before the scan, they will have blood and urine tests and a test of their heart function. The tracer will be given through a tube attached to a needle inserted into a vein in the arm. They will lie on a padded bed that fits inside a doughnut-shaped machine; the machine uses x-rays to create images of the inside of the body.

Some participants will have a PET/CT scan of their whole body. They will need only 1 visit.

Some participants will have a PET/CT scan of only their brain. They will have up to 2 visits. On the second visit, they will have a magnetic resonance imaging (MRI) scan of the brain. For the MRI, they will lie on a table that slides into a cylinder. The MRI uses magnetic fields to create images of the inside of the body.

Participants will receive a follow-up call to check on their well-being after their PET/CT scans.

Study Overview

• Status: Recruiting
• Conditions: Healthy
• Intervention / Treatment: Drug: 11C-ARMI

Detailed Description

Study Description:

This study is intended to provide information on the novel 11C-ARMI radioligand and its ability to localize and measure Alpha-1A Adrenoreceptor (alpha-1A AR) in the brain and body of healthy volunteers.

Objectives:

Primary Objective:

To study the brain uptake of 11C-ARMI and perform kinetic modeling of 11C-ARMI in healthy volunteers.

Secondary Objectives:

To study brain retest variability and reliability, biodistribution, and dosimetry of 11C-ARMI in healthy volunteers.

Endpoint:

Primary Endpoint:

For both objectives, the primary endpoint is receptor density measured as distribution volume (VT).

Secondary Endpoint:

Radiation burden to the body and expressed as Effective Dose (ED).

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Robert B Innis, M.D.; Phone Number: (301) 594-1368; Email: robert.innis@nih.gov
• Study Contact Backup: Name: Tara N Turon, C.R.N.P.; Phone Number: (301) 827-6599; Email: tara.turon@nih.gov

Study Locations

• United States
  • Maryland
    • Bethesda, Maryland, United States, 20892
      • Recruiting
      • National Institutes of Health Clinical Center
      • Contact: NIH Clinical Center Office of Patient Recruitment (OPR); Phone Number: TTY dial 711 800-411-1222; Email: ccopr@nih.gov

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

• INCLUSION CRITERIA:

  1. Aged 18 years or older.
  2. Must have undergone a screening assessment under protocol 01-M-0254, The Evaluation of Patients with Mood and Anxiety Disorders and Healthy Participants or 17M0181 Recruitment and Characterization of Healthy Research Volunteers for NIMH Intramural Studies.
  3. Be healthy based on medical history, physical examination, and laboratory testing.
  4. Able to understand and willingness to provide informed consent.
  5. Willingness to complete all study procedures including MRI tests.
  6. Have had their radial artery pulse checked for the presence of adequate ulnar collateral flow and the absence of any metal or foreign objects in both wrists.
  7. Agree to adhere to the lifestyle considerations

EXCLUSION CRITERIA:

An individual who meets any of the following criteria will be excluded from participation in this study:

1. Clinically significant abnormalities on EKG or laboratory testing. This includes CBC and acute care panel (Na, K, Cl, CO2, creatinine, glucose, urea nitrogen).
2. Recent exposure to radiation (i.e., PET from other research) that, when combined with this study, would be above the allowable limits.
3. Inability to lie flat on camera bed for at least two hours, including claustrophobia and weight greater than the maximum for the scanner (500 lbs).
4. HIV infection.
5. Pregnancy or breastfeeding.
6. Must not have substance use disorder or alcohol use disorder.
7. Unable to travel to the NIH.
8. Unable to have an MRI scan (e.g., because of pacemakers or other implanted electrical devices, brain stimulators, dental implants, aneurysm clips (metal clips on the wall of a large artery), metallic prostheses (including metal pins and rods, heart valves, and cochlear implants), permanent eyeliner, implanted delivery pumps, shrapnel fragments, or metal fragments in the eye.
9. Taking medications reported to have significant binding to alpha-1 adrenoceptors, medications that that alter norepinephrine release, or medications that lower blood pressure including antihypertensives, diuretics, or phosphodiesterase-5(PDE-5) inhibitors (e.g. sildenafil, tadalafil, vardenafil) within five elimination halflives prior to any [11C]ARMI PET scan.
10. Known hypersensitivity to quinazoline-class medications (e.g., prazosin), defined as any prior allergic or clinically significant adverse reaction requiring discontinuation or medical evaluation.
11. Blood donation within 8 weeks (2 months) before study participation, or unwillingness to avoid blood donation for 8 weeks (2 months) after the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: One-arm; All subjects will receive the same tests.	Drug: 11C-ARMI; Injected IV followed by PET scanning

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To measure distribution volume	Target quantification	24 months

Secondary Outcome Measures

Outcome Measure	Time Frame
To measure variability distribution volume	24 months

Collaborators and Investigators

• Sponsor: National Institute of Mental Health (NIMH)
• Investigators: Principal Investigator: Robert B Innis, M.D., National Institute of Mental Health (NIMH)

Publications and helpful links

Helpful Links

• NIH Clinical Center Detailed Web Page

Study record dates

Study Major Dates

• Study Start (Estimated): July 15, 2026
• Primary Completion (Estimated): February 5, 2029
• Study Completion (Estimated): February 20, 2030

Study Registration Dates

• First Submitted: July 3, 2026
• First Submitted That Met QC Criteria: July 6, 2026
• First Posted (Actual): July 7, 2026

Study Record Updates

• Last Update Posted (Actual): July 10, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 2, 2026

More Information

Terms related to this study

• Keywords: Healthy; Positron Emission Tomography (PET) Imaging; 11C-ARMI; Alpha-1A Adrenoreceptor ( 1A-AR)
• Other Study ID Numbers: 10002497; 002497-M

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The results will be submitted to ClinicalTrials.gov
• IPD Sharing Time Frame: 18 months after closure of protocol.
• IPD Sharing Access Criteria: BTRIS
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No