Clinical Validation of Birch Pollen in the EEU

Controlled Birch Pollen Challenge in the Environmental Exposure Unit (EEU); Clinical Validation and Biomarker Exploration

The EEU has proven effective in multiple studies evaluating various aspects of seasonal allergic rhinitis. All previous EEU clinical trials have utilized ragweed or grass pollen as the allergen of choice for dispersal, due to the local population, but many emerging treatments for allergic rhinitis are allergen specific, thus it is desirable to expand the repertoire of pollen selection for use in the EEU. Ragweed, grass and birch pollen have differing appearances and sizes but essentially, both have characteristics which promote the ability to keep the pollen grains suspended and hence, the ability to maintain proper concentrations within the EEU. Preliminary validation studies conducted in the EEU, absent of human volunteers, have confirmed our ability to release, disperse and maintain birch pollen concentrations in the EEU using the existing technology.

This study aims to validate the use of birch pollen on a clinical scale. By adding non- allergic participants into the EEU, the investigators hope to determine if non-allergic persons exhibit differences at baseline in their "epigenetic biomarkers" from those who have pre-existing and established allergic airways inflammation.

Study Overview

• Status: Completed
• Conditions: Allergic Rhinitis
• Intervention / Treatment: Other: Birch Pollen; Procedure: Nasal Brushing

Detailed Description

The Environmental Exposure Unit (EEU) is a controlled allergen challenge model of allergic rhinitis ('hayfever') that has been used extensively to study various anti-allergic therapies. The EEU is a unique, internationally recognized research facility that allows for the exposure of groups of as few as 5 to as many as 150 volunteers simultaneously to ambient levels of airborne allergens such as ragweed pollen and provides a unique study environment ideally suited to evaluate efficacy and onset of action of various anti-allergic medications. This specialized facility, located within Kingston General Hospital, allows for the tight regulation of environmental variables such as air quality, temperature, humidity and CO2 levels as well as the precise maintenance of allergen concentration within this specialized room. Thus the EEU provides a closed environment in which participants are exposed to a predetermined, controlled, constant level of airborne pollen. All previous studies have used either ragweed or grass pollen, and the investigators have not clinically validated the use of birch pollen in the EEU. This study will confirm that the birch pollen circulated in the EEU can generate allergic rhinitis symptoms similar to those seen in the 'real world', and will also provide an opportunity to collect blood from participants before and after allergen challenge in order to better understand allergic inflammation, to hopefully someday identify novel therapies in allergic disease.

This study will consist of a Screening Visit and one pollen exposure visit. The duration of each participant's participation in the study from Screening to End of Study (EOS) will be approximately 3 weeks. The study population will consist of healthy, ambulatory male and female volunteers, 18-65 years of age with either a history of seasonal allergic rhinitis or a history of no allergic reactions. Approximately 55-75 participants will be screened to ensure 50 eligible participants are enrolled into the study (40 allergic, 10 non-allergic).

All participants will give written informed consent prior to any study procedures being performed. Participants who meet all inclusion/exclusion criteria during the screening process will be asked to return to the EEU for their pollen exposure visit. At the Screening visit participants will provide a full medical history and undergo a physical examination. They will have their height/weight and vitals measured and skin testing will be performed to confirm allergic response to a panel of common aeroallergens (or lack of response for the non-allergic individuals). Women of child bearing potential will undergo a urine pregnancy test to rule out pregnancy. Eligible participants will be asked to return to the research site for one 4 hour exposure to birch pollen in the Environmental Exposure Unit (EEU). Peripheral blood samples will be collected before and after pollen exposure for measurement of potential biomarkers.

• Study Type: Interventional
• Enrollment (Actual): 59
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Kingston, Ontario, Canada, K7L 2V7
      • Kingston General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• minimum 2 year document history of rhinoconjunctivitis during typical tree pollen season (mid March to early May) OR completely non-atopic (allergic) to all environmental allergens.
• positive skin test to birch allergen OR negative skin test to a panel of allergens at screening.

Exclusion Criteria:

• participants with asthma.
• participant is pregnant, lactating or actively trying to conceive.
• participant is currently receiving allergen specific immunotherapy.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Total Nasal Symptom Score from Baseline to each time point.	Participants will assess their symptoms every 30 minutes during the 4-hour pollen exposure session and the sum of the 4 nasal symptoms (runny nose, stuffy nose, sneezing and itchy nose) which create the Total Nasal Symptom Score (TNSS)	Second and Final Visit (4 hour pollen exposure)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of people achieving a TNSS of 6 or greater	The data will be evaluated to see how many participants achieved a TNSS of 6 or greater (out of a possible 12) at the second hour of pollen exposure. This is typically the time frame for qualification for randomization in a clinical trial.	Second and Final Visit (4 hour pollen exposure)
Percentage of people achieving a TRSS of 10 or greater	The data will be evaluated to see how many participants achieved a TRSS of 10 or greater (out of a possible 24) during the second hour of pollen exposure.	Second and Final Visit (4 hour pollen exposure)
Change in Total Rhinoconjunctivitis Symptom Score from Baseline to each time point.	Participants will assess their symptoms every 30 minutes during the 4-hour pollen exposure session and the sum of all of their symptoms (nasal symptoms listed above as well as itchy eyes, watery/tearing eyes, red burning eyes and itching of the ears/palate/throat) which create the Total Rhinoconjunctivitis Symptom Score (TRSS)	Second and Final Visit (4 hour pollen exposure)
Change in Peak Nasal Expiratory Flow (PNIF) from baseline at each time point.	Participants will measure their nasal blockage using a Peak Nasal Inspiratory Flow meter every 30 minutes at the same time that they measure the rest of their symptoms. As the participant's nose become more congested this value should decrease.	Second and Final Visit (4 hour pollen exposure)

Collaborators and Investigators

• Sponsor: Queen's University
• Collaborators: University of British Columbia
• Investigators: Principal Investigator: Anne K Ellis, MD, Queen's University

Publications and helpful links

General Publications

• Ellis AK, Soliman M, Steacy LM, Adams DE, Hobsbawn B, Walker TJ. Clinical validation of controlled exposure to birch pollen in the Environmental Exposure Unit (EEU). Allergy Asthma Clin Immunol. 2016 Oct 19;12:53. doi: 10.1186/s13223-016-0156-7. eCollection 2016.

Study record dates

Study Major Dates

• Study Start: January 1, 2015
• Primary Completion (Actual): March 1, 2015
• Study Completion (Actual): March 1, 2015

Study Registration Dates

• First Submitted: January 27, 2015
• First Submitted That Met QC Criteria: January 29, 2015
• First Posted (Estimate): January 30, 2015

Study Record Updates

• Last Update Posted (Estimate): April 21, 2015
• Last Update Submitted That Met QC Criteria: April 20, 2015
• Last Verified: April 1, 2015

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Infections; Respiratory Tract Infections; Respiratory Tract Diseases; Immune System Diseases; Hypersensitivity, Immediate; Otorhinolaryngologic Diseases; Respiratory Hypersensitivity; Hypersensitivity; Nose Diseases; Rhinitis; Rhinitis, Allergic
• Other Study ID Numbers: Birch Validation Study