Effects of Multiple Nasal Exposures to House Dust Mite Allergen on Nasal and Body Inflammation and Airway Sensitivity

Inclusion Criteria: * Healthy non-smoking subjects with a history of allergic rhinitis consistent with dust mite allergy showing * A positive skin prick test to dust mite at or within the 12 months before study start * Demonstrate symptomatic worsening after graded nasal allergen challenge Exclusion Criteria: * Subjects found to be very sensitive to house dust mites (if the skin prick test produces a wheal of mean with a diameter greater than 11 mm). * Presence of any respiratory disease other than a history of mild stable asthma not requiring regular treatment. * Any known contraindications for methacholine challenge testing Other protocol-defined inclusion/exclusion criteria may apply.