Trial Outcomes & Findings for Hyperpolarized Xenon-129 Magnetic Resonance Imaging and Spectroscopy of Brown Fat: Healthy Adult Volunteer Pilot Study (NCT NCT02220426)
NCT ID: NCT02220426
Last Updated: 2025-11-25
Results Overview
For each subject, the brown adipose tissue (BAT) surface area is derived from 2D MR images acquired without slice selection, obtained before and during cold exposure. Each image consists of Nx × Ny pixels, each having an in-plane pixel area (Apixel, in millimeters squared) calculated as: Apixel=(FOVx/Nx)×(FOVy/Ny), where FOVx and FOXy are the field-of-view dimensions in millimeters in the x and y directions, respectively. BAT-positive pixels are defined as those whose signal intensity increases by more than 5% during cold stimulation relative to baseline. The total BAT surface area (ABAT, in millimeters squared) is then computed as: ABAT=NBAT×Apixel where NBAT is the number of BAT-positive pixels for each subject. This approach yields the total in-plane area of activated BAT within the 2D field of view for each subject. The value obtained for all subjects was then averaged.
TERMINATED
PHASE1
17 participants
Day 1
2025-11-25
Participant Flow
Participant milestones
| Measure |
Xenon Inhalation
Inhalation of up to 5 doses of 750ml of hyperpolarized 129Xe gas
Xenon: Inhalation of hyperpolarized xenon gas
|
|---|---|
|
Overall Study
STARTED
|
17
|
|
Overall Study
Signed Informed Consent
|
17
|
|
Overall Study
Received Xenon Inhalation
|
13
|
|
Overall Study
COMPLETED
|
13
|
|
Overall Study
NOT COMPLETED
|
4
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Hyperpolarized Xenon-129 Magnetic Resonance Imaging and Spectroscopy of Brown Fat: Healthy Adult Volunteer Pilot Study
Baseline characteristics by cohort
| Measure |
Xenon Inhalation
n=13 Participants
Inhalation of up to 5 doses of 750ml of hyperpolarized 129Xe gas
Xenon: Inhalation of hyperpolarized xenon gas
|
|---|---|
|
Age, Continuous
|
26.6 years
STANDARD_DEVIATION 8.5 • n=45 Participants
|
|
Sex: Female, Male
Female
|
8 Participants
n=45 Participants
|
|
Sex: Female, Male
Male
|
5 Participants
n=45 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
0 Participants
n=45 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
13 Participants
n=45 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=45 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=45 Participants
|
|
Race (NIH/OMB)
Asian
|
2 Participants
n=45 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=45 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=45 Participants
|
|
Race (NIH/OMB)
White
|
11 Participants
n=45 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=45 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=45 Participants
|
|
Region of Enrollment
United States
|
13 Participants
n=45 Participants
|
PRIMARY outcome
Timeframe: Day 1Population: No imaging data were collected for 9 participants because the Xenon signal did not reach the needed threshold required for imaging.
For each subject, the brown adipose tissue (BAT) surface area is derived from 2D MR images acquired without slice selection, obtained before and during cold exposure. Each image consists of Nx × Ny pixels, each having an in-plane pixel area (Apixel, in millimeters squared) calculated as: Apixel=(FOVx/Nx)×(FOVy/Ny), where FOVx and FOXy are the field-of-view dimensions in millimeters in the x and y directions, respectively. BAT-positive pixels are defined as those whose signal intensity increases by more than 5% during cold stimulation relative to baseline. The total BAT surface area (ABAT, in millimeters squared) is then computed as: ABAT=NBAT×Apixel where NBAT is the number of BAT-positive pixels for each subject. This approach yields the total in-plane area of activated BAT within the 2D field of view for each subject. The value obtained for all subjects was then averaged.
Outcome measures
| Measure |
Xenon Inhalation
n=7 2-D images
Inhalation of 5 doses of 750ml of hyperpolarized 129Xe gas
Xenon: Inhalation of hyperpolarized xenon gas
|
|---|---|
|
Brow Adipose Tissue Surface Area
|
3541 millimiters squared
Standard Deviation 2474
|
SECONDARY outcome
Timeframe: Day 1Population: Temperature measurements were not performed because the xenon and proton spectra were acquired with different magnet settings, which prevented alignment of the signals required for calculation.
Change in BAT temperature (in degree Celsius) will be estimated from xenon nuclear magnetic resonance (NMR) spectra acquired at thermoneutrality and during cold exposure. Both proton (1H) and xenon (129Xe) spectra are required to perform the temperature calculation.
Outcome measures
Outcome data not reported
Adverse Events
Xenon Inhalation
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Xenon Inhalation
n=13 participants at risk
Inhalation of 5 doses of 750ml of hyperpolarized 129Xe gas
Xenon: Inhalation of hyperpolarized xenon gas
|
|---|---|
|
Nervous system disorders
Restlessness
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Nervous system disorders
Numbness
|
61.5%
8/13 • Number of events 8 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Psychiatric disorders
Euphoria
|
15.4%
2/13 • Number of events 2 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Nervous system disorders
Tingling
|
61.5%
8/13 • Number of events 8 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Ear and labyrinth disorders
Tinnitus
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Nervous system disorders
Lightheadedness
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Ear and labyrinth disorders
Vertigo
|
38.5%
5/13 • Number of events 5 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Injury, poisoning and procedural complications
Device site discomfort
|
38.5%
5/13 • Number of events 5 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Nervous system disorders
Somnolence (sleepiness)
|
15.4%
2/13 • Number of events 2 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Cardiac disorders
Chest discomfort (twinge following inhalation)
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Vascular disorders
Increase in blood pressure prior inhalation
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Musculoskeletal and connective tissue disorders
Back pain from lying in scanner
|
7.7%
1/13 • Number of events 1 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
|
Nervous system disorders
Dizziness
|
46.2%
6/13 • Number of events 6 • Within two minutes after xenon inhalation and continuing through and ending at one hour after the last xenon inhalation, a total of up to 1 hour in total.
|
Additional Information
Rosa Tamara Branca, PhD
University of North Carolina at Chapel Hill
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place