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Imaging Study of the Lungs During an Allergic Asthma Attack

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT01547286
First Posted: March 7, 2012
Last Update Posted: November 22, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Collaborator:
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Robert Scott Harris, M.D., Massachusetts General Hospital
Results First Submitted: May 8, 2015  
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

  Participant Flow
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Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
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
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
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.

Reporting Groups
  Description
Allergic Asthmatic 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.

Participant Flow:   Overall Study
    Allergic Asthmatic
STARTED   7 
COMPLETED   5 
NOT COMPLETED   2 
Did not meet all eligibility criteria                1 
Physician Decision                1 



  Baseline Characteristics
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Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
7 Subjects were enrolled and 5 subjects completed the study. Demographics and metacholine challenge test were obtained from all 7 subjects.

Reporting Groups
  Description
Allergic Asthmatic 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

Baseline Measures
   Allergic Asthmatic 
Overall Participants Analyzed 
[Units: Participants]
 7 
Age 
[Units: Participants]
Count of Participants
 
<=18 years      0   0.0% 
Between 18 and 65 years      7 100.0% 
>=65 years      0   0.0% 
Age 
[Units: Years]
Mean (Standard Deviation)
 22.7  (5.08) 
Sex: Female, Male 
[Units: Participants]
Count of Participants
 
Female      6  85.7% 
Male      1  14.3% 
Region of Enrollment 
[Units: Participants]
 
United States   7 


  Outcome Measures
  Show All Outcome Measures

1.  Primary:   Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside   [ Time Frame: 3 hours after allergen administration ]

2.  Primary:   Percentage Change in the Ratio of Mean-normalized Perfusion Within Ventilation Defective Regions Relative to Outside   [ Time Frame: 7 hours after allergen administration ]

3.  Secondary:   Coefficient of Variation Squared of Perfusion   [ Time Frame: 3 hours after allergen administration ]

4.  Secondary:   Coefficient of Variation Squared of Perfusion   [ Time Frame: 7 hours after allergen administration ]


  Serious Adverse Events


  Other Adverse Events


  Limitations and Caveats
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Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
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  More Information
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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
e-mail: rsharris@mgh.harvard.edu



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