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Imaging Study of the Lungs During an Allergic Asthma Attack

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ClinicalTrials.gov Identifier: NCT01547286
Recruitment Status : Completed
First Posted : March 7, 2012
Results First Posted : April 25, 2017
Last Update Posted : November 22, 2017
Sponsor:
Collaborator:
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Robert Scott Harris, M.D., Massachusetts General Hospital

Study Type Interventional
Study Design Intervention Model: Single Group Assignment;   Masking: None (Open Label);   Primary Purpose: Basic Science
Conditions Asthma
Atopy
Interventions Biological: Standardized Cat Allergen Extract and Standardized Dust Mite Allergen
Radiation: Computed Tomography imaging, functional Positron Emission Tomography imaging
Drug: Nebulized methacholine inhalation
Enrollment 7
Recruitment Details Subjects were recruited using an IRB approved advertisement from December 2012 - January 2013. Potential subjects completed two screening visits, during which the informed consent was obtained, clinical assessment, spirometry, methacholine challenge and allergic skin tests were performed. All screening visits took place at our pulmonary clinics.
Pre-assignment Details This is a single group design study. Subjects were instructed to withhold their asthma and allergy medications before the screening and bronchial allergen challenge tests. The duration of the medication withholding depended on which medications they were using at that time.
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description This is a single physiological group study where each subject served as their own control. All eligible subjects underwent a methacholine challenge test, clinical assessment and skin tests to ascertain the diagnosis of allergic asthma. Both methacholine and skin test results were used to determine the start dose of the bronchial allergen challenge test. CT and PET with Nitrogen-13 (13NN) saline as a radiotracer images were obtained during the early and late phases after allergen challenge.
Period Title: Overall Study
Started 7
Completed 5
Not Completed 2
Reason Not Completed
Did not meet all eligibility criteria             1
Physician Decision             1
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description Standardized Cat Allergen Extract and Standardized Dust Mite Allergen: The route of administration will be topical application of the titrated allergen via nebulized droplets to the lungs. The starting dose of allergen will be 3 dose dilutions below the estimated PC20-allergen delivered for 5 minutes at tidal breathing, followed by FEV1 at 10-minute intervals until the lowest FEV1 is established. If the %FEV1 fall is < 20%, the next concentration is given, until the FEV1 falls ≥ 20%. When this happens the FEV1 will be followed at 10, 20, 30, 45, and 60 minutes, then hourly for 7 hours. The early asthmatic response is the maximum %FEV1 fall between 0 and 3 hours and the late asthmatic response between 3 and 7 hours post allergen challenge.CT imaging, functional PET imaging: Physiology study using CT and PET imaging with Nitrogen-13 (13NN) saline as radiotracer; images obtained during the early and late phases after allergen challenge. Nebulized methacholine inhalation: Standard
Overall Number of Baseline Participants 7
Hide Baseline Analysis Population Description
7 Subjects were enrolled and 5 subjects completed the study. Demographics and metacholine challenge test were obtained from all 7 subjects.
Age, Categorical  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 7 participants
<=18 years
0
   0.0%
Between 18 and 65 years
7
 100.0%
>=65 years
0
   0.0%
Age, Continuous  
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 7 participants
22.7  (5.08)
Sex: Female, Male  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 7 participants
Female
6
  85.7%
Male
1
  14.3%
Region of Enrollment  
Measure Type: Number
Unit of measure:  Participants
United States Number Analyzed 7 participants
7
1.Primary Outcome
Title Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside
Hide Description Blood flow relative to the mean blood flow of the lung (mean normalized perfusion) inside areas that have reduced ventilation (Vdefs) relative to outside the Vdefs. Or, another way of writing this is: (Blood flow inside Vdefs/mean blood flow of the lung)/(Blood flow outside Vdefs/mean blood flow of the lung).
Time Frame 3 hours after allergen administration
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description:

Standardized Cat Allergen Extract and Standardized Dust Mite Allergen: The route of administration will be topical application of the titrated allergen via nebulized droplets to the lungs. The starting dose of allergen will be 3 dose dilutions below the estimated PC20-allergen delivered for 5 minutes at tidal breathing, followed by FEV1 at 10-minute intervals until the lowest FEV1 is established. If the %FEV1 fall is < 20%, the next concentration is given, until the FEV1 falls ≥ 20%. When this happens the FEV1 will be followed at 10, 20, 30, 45, and 60 minutes, then hourly for 7 hours. The early asthmatic response is the maximum %FEV1 fall between 0 and 3 hours and the late asthmatic response between 3 and 7 hours post allergen challenge.

CT imaging, functional PET imaging: Physiology study using CT and PET imaging with Nitrogen-13 (13NN) saline as radiotracer; images obtained during the early and late phases after allergen challenge Nebulized methacholine inhalation: Standard

Overall Number of Participants Analyzed 5
Mean (Standard Deviation)
Unit of Measure: percentage
-17.8  (5.1)
2.Primary Outcome
Title Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside
Hide Description Blood flow relative to the mean blood flow of the lung (mean normalized perfusion) inside areas that have reduced ventilation (Vdefs) relative to outside the Vdefs. Or, another way of writing this is: (Blood flow inside Vdefs/mean blood flow of the lung)/(Blood flow outside Vdefs/mean blood flow of the lung).
Time Frame 7 hours after allergen administration
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description:

Standardized Cat Allergen Extract and Standardized Dust Mite Allergen: The route of administration will be topical application of the titrated allergen via nebulized droplets to the lungs. The starting dose of allergen will be 3 dose dilutions below the estimated PC20-allergen delivered for 5 minutes at tidal breathing, followed by FEV1 at 10-minute intervals until the lowest FEV1 is established. If the %FEV1 fall is < 20%, the next concentration is given, until the FEV1 falls ≥ 20%. When this happens the FEV1 will be followed at 10, 20, 30, 45, and 60 minutes, then hourly for 7 hours. The early asthmatic response is the maximum %FEV1 fall between 0 and 3 hours and the late asthmatic response between 3 and 7 hours post allergen challenge.

CT imaging, functional PET imaging: Physiology study using CT and PET imaging with Nitrogen-13 (13NN) saline as radiotracer; images obtained during the early and late phases after allergen challenge Nebulized methacholine inhalation: Standard

Overall Number of Participants Analyzed 5
Mean (Standard Deviation)
Unit of Measure: percentage
-26.3  (9.8)
3.Secondary Outcome
Title Coefficient of Variation Squared of Perfusion
Hide Description Coefficient of variation squared of the perfusion in the imaged lung. This measures the overall heterogeneity of perfusion in the imaged lung.
Time Frame 3 hours after allergen administration
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description:
All subjects were allergic asthmatics, each served as their own control. There was no comparator group.
Overall Number of Participants Analyzed 5
Mean (Standard Deviation)
Unit of Measure: unitless
0.11  (0.03)
4.Secondary Outcome
Title Coefficient of Variation Squared of Perfusion
Hide Description Coefficient of variation squared of the perfusion in the imaged lung. This measures the overall heterogeneity of perfusion in the imaged lung.
Time Frame 7 hours after allergen administration
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
[Not Specified]
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description:
All subjects were allergic asthmatics, each served as their own control. There was no comparator group.
Overall Number of Participants Analyzed 5
Mean (Standard Deviation)
Unit of Measure: unitless
0.15  (0.07)
Time Frame Subjects were monitored throughout the study and there were no adverse events.
Adverse Event Reporting Description [Not Specified]
 
Arm/Group Title Allergic Asthmatic
Hide Arm/Group Description

Standardized Cat Allergen Extract and Standardized Dust Mite Allergen: The route of administration will be topical application of the titrated allergen via nebulized droplets to the lungs. The starting dose of allergen will be 3 dose dilutions below the estimated PC20-allergen delivered for 5 minutes at tidal breathing, followed by FEV1 at 10-minute intervals until the lowest FEV1 is established. If the %FEV1 fall is < 20%, the next concentration is given, until the FEV1 falls ≥ 20%. When this happens the FEV1 will be followed at 10, 20, 30, 45, and 60 minutes, then hourly for 7 hours. The early asthmatic response is the maximum %FEV1 fall between 0 and 3 hours and the late asthmatic response between 3 and 7 hours post allergen challenge.

CT imaging, functional PET imaging: Physiology study using CT and PET imaging with Nitrogen-13 (13NN) saline as radiotracer; images obtained during the early and late phases after allergen challenge

All-Cause Mortality
Allergic Asthmatic
Affected / at Risk (%)
Total   --/-- 
Show Serious Adverse Events Hide Serious Adverse Events
Allergic Asthmatic
Affected / at Risk (%)
Total   0/7 (0.00%) 
Show Other (Not Including Serious) Adverse Events Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 0%
Allergic Asthmatic
Affected / at Risk (%)
Total   0/7 (0.00%) 
Certain Agreements
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
Results Point of Contact
Name/Title: Dr. Robert Scott Harris, MD
Organization: Massachusetts General Hospital
Phone: 617-726-9429
Responsible Party: Robert Scott Harris, M.D., Massachusetts General Hospital
ClinicalTrials.gov Identifier: NCT01547286     History of Changes
Other Study ID Numbers: 2007P002386
1R01HL086717-01A2 ( U.S. NIH Grant/Contract )
First Submitted: February 15, 2012
First Posted: March 7, 2012
Results First Submitted: May 8, 2015
Results First Posted: April 25, 2017
Last Update Posted: November 22, 2017