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PAXT: Pulmonary Imaging of Mild Asthma Using 129Xe MRI and Tc-99-Labeled-Carbon-Imaging (Tc99CImaging)

PAXT: Pulmonary Imaging of Mild Asthma Using 129Xe MRI and Tc-99-Labeled-Carbon-Imaging (Tc99CImaging)

Status
Not yet recruiting
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT07143747
Acronym
PAXT
Enrollment
40
Registered
2025-08-27
Start date
2025-09-30
Completion date
2028-12-31
Last updated
2025-08-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Mild Asthma

Keywords

Hyperpolarized 129Xe MRI, Technegas Ventilation Imaging, Pulmonary Function Testing, Mild Asthma, Ventilation Defects

Brief summary

The goal of this observational study is to better understand how asthma affects the lungs in young adults (ages 17-35) with mild asthma. The main questions it aims to answer are: * Can advanced imaging detect abnormal airway function in people with mild asthma? * Do changes in ventilation imaging correlate with asthma symptoms or quality of life? Researchers will compare hyperpolarized xenon-129 MRI and Technegas (Tc-99m) imaging to see if these techniques reveal more detailed lung abnormalities than standard lung function tests. Participants will: * Complete a single 2-hour visit * Undergo two types of lung imaging: Hyperpolarized xenon-129 MRI (to visualize how air moves in the lungs), Technegas (Tc-99m) imaging (to assess airflow using nuclear medicine) * Perform spirometry and other breathing tests * Answer questionnaires about asthma symptoms and quality of life This study is designed to improve our understanding of subtle changes in lung function that may not be detected by standard tests in people with mild asthma. The findings may lead to better diagnostic tools and more personalized treatment strategies in the future.

Detailed description

This is a single centre, study in university-aged participants diagnosed with mild asthma as indicated by a prescription for a short acting bronchodilator for use as needed. Each participant will participate in one research study visit which includes pre- and post- bronchodilator (BD) spirometry, plethysmography, oscillometry, 129Xe MRI as well as pre-BD ultra-low dose chest CT, Tc99CImaging, blood CBC, sputum induction, as well as completion of the ACQ and AQLQ questionnaires.

Interventions

Inhalation of hyperpolarized 129Xe gas followed by breath-hold MRI for ventilation imaging.

OTHERTc-99m Technegas Ventilation Imaging

Inhalation of Tc-99m-labeled carbon aerosol (Technegas) followed by SPECT imaging to assess lung ventilation.

Sponsors

Cyclomedica Australia PTY Limited
CollaboratorINDUSTRY
Dr. Grace Parraga
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
CROSS_SECTIONAL

Eligibility

Sex/Gender
ALL
Age
17 Years to 35 Years
Healthy volunteers
No

Inclusion criteria

Participants eligible for inclusion in this study must meet all of the following criteria: 1. Participant diagnosed with mild (GINA1) asthma by physician 2. Participant understands study procedures and is willing to participate in the study as indicated by the participant's signature 3. Provision of written, informed consent prior to any study specific procedures 4. Males and females 17 to 35 years of age 5. Women of childbearing potential (after menarche) must ensure that they are using an effective form of birth control for at least 2 months prior to each imaging visit. Examples of effective birth control include: 1. True sexual abstinence 2. A vasectomized sexual partner 3. Implanon® 4. Female sterilization by tubal occlusion 5. Effective intrauterine device (IUD)/levonogestrel intrauterine system (IUS) 6. Depo-Provera™ injections 7. Oral contraceptive 8. Evra Patch™ 9. Nuvaring™

Exclusion criteria

Participants fulfilling any of the following criteria are not eligible for inclusion in this study: 1. Participant has an implanted mechanically, electrically, or magnetically activated device or any metal in their body which cannot be removed, including but not limited to pacemakers, neurostimulators, biostimulators, implanted insulin pumps, aneurysm clips, bioprosthesis, artificial limb, metallic fragment or foreign body, shunt, surgical staples (including clips or metallic sutures and/or ear implants) (at the discretion of the MRI Technologist) 2. In the investigator's opinion, subject suffers from any physical, psychological or other condition(s) that might prevent performance of the MRI, CT, or Tc99CImaging, such as severe claustrophobia 3. Participants who are pregnant, breastfeeding or have a positive pregnancy test at initial screening visit 4. Participant is unable to perform spirometry or plethysmography maneuvers 5. Participant is unable to perform MRI and CT breath-hold maneuvers

Design outcomes

Primary

MeasureTime frameDescription
Measure 129Xe and Tc99C Imaging ventilation defects qualitatively and quantitatively in participants diagnosed and treated as mild asthma.1 baseline visit for pre- and post-bronchodilator imaging assessmentsVentilation defects will be assessed using 129Xe MRI and Tc-99m Technegas SPECT imaging. Measurements will include ventilation defect percentage (VDP) and visual scoring to evaluate ventilation abnormalities in participants with mild asthma.

Secondary

MeasureTime frameDescription
Evaluate the relationships of MRI and Tc99CImaging ventilation defects with ACQ, oscillometry (R5-19) and FEV11 baseline visitIn this exploratory study, we hypothesize that there will be significant relationships between ventilation abnormalities and oscillometry as well as FEV1 and asthma control questionnaire (ACQ) score.

Countries

Canada

Contacts

Primary ContactGrace E Parraga, PhD
gparraga@robarts.ca519-931-5777
Backup ContactAngela P Wilson, RRT
awilson@robarts.ca519-931-5777

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026