The role of allergen challenge chambers in the evaluation of anti‐allergic medication: an international consensus paper

Abstract

Summary Allergic rhinitis (AR) is a common condition with quality of life and economic implications for those affected. Numerous studies have attempted to evaluate treatments for rhinitis, seeking clinically meaningful efficacy and safety results to enable evidence‐based treatment decisions. Traditional studies of medications for AR are hampered by many confounding environmental factors as well as suboptimal medication compliance. They are also an unsuitable setting for determination of precise pharmacodynamic properties of medications, including onset and duration of action. Allergen challenge chambers (ACCs) were developed to provide predetermined, controlled allergen levels and to limit variables inherent in traditional studies. An ACC hosts a number of allergen‐sensitive subjects who may receive either medication or placebo in a closed environment regulated for temperature, humidity and other variables. Subjects' allergic responses are monitored using subjective and objective assessments throughout the study, and the resultant information contributes significantly to the clinical profile of a medication. This consensus paper provides an in‐depth review of the role of ACCs as a means to evaluate treatments in AR, and concludes that ACC trials fulfil an important supportive role in the assessment of anti‐allergic medication.

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