Cat Pilot Study - Environmental Exposure Chamber (EEC) vs. Nasal Allergen Challenge (NAC) (CAT EEC Study)

Principal Investigator

Stephen Durham, MD | Imperial College London | London, UK Piyush Patal, MD | Inflamax Research | Ontario, Canada


Inflamax Research, Inc | Ontario, Canada

Study Code


Study Status



The CAT EEC study, “Cat Pilot Study – Environmental Exposure Chamber (EEC) vs. Nasal Allergen Challenge (NAC),” is being conducted at Inflamax Research, Inc. in Ontario, Canada and led by Drs. Stephen Durham (Imperial College London) and Piyush Patel (Inflamax Research, Inc.). The goal of the CAT EEC study is to directly compare allergic responses to cat by environmental exposure chamber vs. nasal allergen challenge to better understand and employ these methods as allergy evaluation tools in clinical trials.

Clinical trials of allergen immunotherapy frequently assess participants’ allergic status by challenging them with direct allergen delivery, such as via nasal spray, to measure corresponding clinical symptoms and other immunologic responses. Nasal allergen challenges are advantageous in that they can be replicated across multiple sites and enable controlled allergen doses, however they do not necessarily reflect real life ambient exposure. An alternative challenge method is via environmental exposure chambers, which are enclosed spaces that control temperature, air flow, and humidity and provide diffuse allergen exposure more closely simulating natural circumstances. 

CAT EEC is a single-site pilot study. After an initial dose-finding phase, 24 cat allergic adults will be randomly assigned to receive either nasal allergen challenge followed by environmental exposure chamber challenge (with a washout period in between), or environmental exposure chamber challenge followed by nasal allergen challenge. The study will measure clinical symptom scores and immunologic biomarkers to help inform endpoint selection for future ITN trials with aeroallergens.