NCT06828484

Allergenic Extract Standardized Cat Hair AP in an Allergic Rhinitis Model.

Evaluating the Clinical and Biological Response of an Acetone-Precipitated Cat Hair Allergen Extract (AP Cat) in a Nasal Allergen Challenge (NAC).

• Status: Active Not Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 20 (estimated)
• Sponsor: Queen's University · Academic / Other
• Sex: All
• Age: 18 Years – 70 Years
• Healthy volunteers: Accepted

Summary

The goal of this study is to learn if a cat allergen extract known as Allergenic Extract Standardized Cat Hair Acetone Precipitated (AP Cat) can induce allergic rhinitis (AR) in a nasal allergen challenge model in cat-allergic people. The main questions this study aims to answer are: 1. Does AP Cat induce nasal symptoms of allergic rhinitis in cat-allergic participants when delivered intranasally? 2. Does AP Cat reduce elements in the blood and nose that are known to be associated with allergies? Both allergic and non-allergic participants will be recruited into this study. Allergic participants will: * Be challenged with AP Cat via the Nasal Allergen Challenge (NAC), which involves administration of this allergen extract directly into the nose. * Have nasal fluid and blood samples collected at various timepoints up to 24 hours after exposure to the allergen in the NAC. * Visit the study site three separate times: 1. At screening (Visit 1), to determine eligibility to participate in this study 2. At the baseline NAC visit (Visit 2) 3. At the 24-hour post-NAC follow-up visit (Visit 3) * Complete nasal symptom questionnaires. * Complete a questionnaire about their regular exposure to cats. Non-allergic participants will: * Be challenged with AP Cat via the NAC, which involves administration of this allergen extract directly into the nose. * Have nasal fluid and blood samples collected at various timepoints up to 24 hours after exposure to the allergen in the NAC. * Visit the study site three separate times: 1. At screening (Visit 1), to determine eligibility to participate in this study 2. At the baseline NAC visit (Visit 2) 3. At the 24-hour post-NAC follow-up visit (Visit 3) * Complete nasal symptom questionnaires. This study will compare the nasal symptoms and allergic markers collected from the nasal fluid and blood samples between allergic and non-allergic participants at baseline and various timepoints post-NAC exposure.

Detailed description

The purpose of this single-centre prospective cohort study is to evaluate the use of AP Cat in the NAC. Allergen extracts are used in skin prick testing, allergy research, and immunotherapy. AP Cat is a new formulation of a cat allergen extract approved for use in skin prick testing, but has not yet been studied in the NAC. This study will enrol non-pregnant and non-lactating female and/or male participants. 15 cat-allergic participants and 5 non-allergic participants from 18-70 years old will be recruited from the Kingston, Frontenac, Lennox, and Addington region in Ontario, Canada. All 20 participants will attend three study visits: Visit 1 (Screening Visit), Visit 2 (NAC Exposure Visit), and Visit 3 (Follow-up Visit). Visit 2 will occur at least 21 days after Visit 1. Visit 3 will occur 24 hours after the onset of the NAC during visit 2. At each visit, symptom scores, nasal fluid samples, and blood samples will be collected. The investigators hypothesize that AP Cat will induce AR-related outcomes (Total Nasal Symptom Score (TNSS), Peak Nasal Inspiratory Flow (PNIF), Total Ocular Symptom Score (TOSS), Total Rhinoconjunctivitis Symptom Score (TRSS)) in cat-allergic participants after exposure in the NAC. The investigators also hypothesize that AP Cat will increase the release of allergic mediators (Interleukin-4 (IL4),IL-5, IL-10, IL-13, Eotaxin-1, Monocyte Chemoattractant Protein-1 (MCP-1), Macrophage Inflammatory Protein-1 Beta (MIP-1β), and alarmins (IL-17E/IL-25, IL-33)) in cat-allergic participants after the NAC. Additionally, the investigators expect that nasal white blood cell counts and peripheral total immunoglobulin E (tIgE) levels will increase in cat-allergic participants after the NAC. Furthermore, the investigators hypothesize that no significant changes to nasal symptoms, allergic mediator levels, nasal eosinophil counts, or tIgE levels will occur in the non-allergic participants, which serve as controls.

Conditions

• Allergic Rhinitis

Interventions

Type	Name	Description
DRUG	Allergenic Extract Standardized Cat Hair Acetone-Precipitated (AP)	Cat-allergic and non-allergic participants will be exposed to AP Cat in the NAC.

Timeline

• Start date: 2025-03-04
• Primary completion: 2026-01-08
• Completion: 2026-06-01
• First posted: 2025-02-14
• Last updated: 2026-01-20

Locations

1 site across 1 country: Canada