Screening Inhaled Allergen Challenge for Dermatophagoides Farinae (MiteScreen)
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|ClinicalTrials.gov Identifier: NCT03049111|
Recruitment Status : Active, not recruiting
First Posted : February 9, 2017
Last Update Posted : April 27, 2020
|Condition or disease||Intervention/treatment||Phase|
|Asthma||Biological: Der f||Early Phase 1|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||100 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Primary Purpose:||Basic Science|
|Official Title:||Screening Inhaled Allergen Challenge for Dermatophagoides Farinae|
|Actual Study Start Date :||January 29, 2018|
|Estimated Primary Completion Date :||March 2022|
|Estimated Study Completion Date :||March 2022|
Experimental: Inhaled Allergen Challenge
Der f sensitive, mild asthmatic subjects will undergo inhaled allergen challenge
Biological: Der f
Inhalation of Der f in mild asthmatics who are sensitive to Der f.
- Decline of FEV1 during the late phase response [ Time Frame: Pre-inhalation challenge and 3-10 hours after inhalation challenge ]Participants will undergo an inhaled allergen challenge to identify those with a measurable late phase response (LPR) to inhaled Dermatophagoides farinae allergen extract. Baseline FEV1 will be measured prior to administration of the allergen challenge. The presence of an LPR will be defined as a decline in FEV1 of ≥15% from baseline values 3-10 hours after the onset of the early phase response (which typically occurs within 30 minutes of allergen challenge).
- Levels of IL-1β in induced sputum [ Time Frame: Baseline and 24 hours post- inhalation challenge ]Participants will undergo a hypertonic saline induced sputum procedure at baseline (within ~2 weeks of the allergen challenge), and again at 24 hours following inhaled allergen challenge. IL-1β concentrations in the sputum will be determined via ELISA. In addition to assessing changes in IL-1β levels, we will determine if IL-1β levels are predictive of key asthma outcomes following inhaled allergen challenge (see outcomes 3-7).
- Sputum granulocytes [ Time Frame: Baseline and 24 hours post- inhalation challenge ]Cellularity of sputum obtained at baseline and again at 24 hours following inhaled allergen challenge will be assessed.
- Mucins in sputum [ Time Frame: Baseline and 24 hours post- inhalation challenge ]Sputum mucins will be measured at baseline, and again at 24 hours following inhaled allergen challenge
- Maximum drop in FEV1 during the late phase response [ Time Frame: Pre-inhalation challenge and 3-10 hours after inhalation challenge ]FEV1 will be measured prior to administration of the inhaled allergen challenge. The maximum drop in FEV1 that occurs during the late phase (3-10 hours after challenge) will be determined.
- Airway hyper-responsiveness [ Time Frame: Baseline and 24 hours post- inhalation challenge ]Participants will undergo a methacholine challenge to assess airway hyper-responsiveness at baseline. Changes in methacholine reactivity from baseline to 24 hours after inhaled allergen challenge will be determined.
- Exhaled nitric oxide (eNO) levels [ Time Frame: Baseline and 24 hours post- inhalation challenge ]eNO levels will be measured at baseline, and 24 hours after inhaled allergen challenge.
- Heart Rate Variability (HRV) [ Time Frame: Pre and immediately post challenge ]HRV with Spacelabs technology will be measured 24 hours pre and during inhalation challenge
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03049111
|United States, North Carolina|
|UNC Center for Environmental Medicine, Asthma and Lung Biology|
|Chapel Hill, North Carolina, United States, 27599-7310|
|Principal Investigator:||Michelle Hernandez, MD||University of North Carolina|