Evaluation of Montelukast for the Treatment of Children With Japanese Cedar Pollinosis Using an Artificial Exposure Chamber (OHIO Chamber)

BackgroundThis study evaluated the efficacy of montelukast in reducing seasonal allergic rhinitis symptoms in Japanese children with Japanese cedar (JC) pollinosis induced in an artificial exposure chamber (OHIO Chamber).MethodsPediatric patients aged 10 to 15 years sensitive to JC pollen entered a randomized, double-blind, single-site, crossover study. After confirmation of an allergic response to a JC pollen exposure for 3 hours in the OHIO Chamber during the screening period, subjects received either montelukast 5 mg chewable tablets or placebo for a 7-day treatment period, followed by a 3-hour pollen exposure in the chamber. After a 7-day washout period, subjects crossed over to the other treatment. Subjects were instructed to self-assess their nasal symptoms using 5-point scale for every 30 minutes. The primary end point was the change from baseline (just before entering the exposure chamber for each exposure) in total nasal symptom score (TNSS; the sum of nasal congestion, nasal discharge, and sneez...