ASCIA‐P48: EFFICACY OF 300IR SUBLINGUAL TABLET OF HOUSE DUST MITE ALLERGEN EXTRACTS IN ADOLESCENTS WITH HOUSE DUST MITE‐ASSOCIATED ALLERGIC RHINITIS

Abstract

The 300IR dose of sublingual house dust mite (HDM) tablet is approved for treatment of HDM-associated allergic rhinitis (AR) in adults and adolescents. Here we focus on Phase II/III study efficacy results in the adolescents. In a randomized, double-blind study conducted in Japan, adults and adolescents (12–64 years) with medically confirmed HDM-associated AR received a 300IR or 500IR HDM tablet or placebo once daily for one year. The primary efficacy endpoint was the Adjusted Symptom Score (ASS, a symptom score adjusted for rescue medication use; scale 0–15) over the last 8 weeks of treatment. Secondary endpoints included the Rhinitis Total Symptom Score (RTSS) and individual rhinitis symptom scores (sneezing, rhinorrhea, nasal pruritus, nasal congestion). All endpoints were analyzed using a mixed-effects model with repeated measures. Of the 968 randomized subjects, 57 adolescents (12–17 years) receiving 300IR and 59 placebo-recipients were included in the efficacy analysis set. In this subset, a statistically significant difference (p < 0.0001) between 300IR and placebo was observed on the primary efficacy endpoint. Over the last 8 weeks of treatment, the average ASS Least-Squares (LS) mean difference vs. placebo was −2.04 (CI95 % [−3.01, −1.08]) for 300IR corresponding to a relative reduction from placebo of −26.9%. The average RTSS LS mean was also significantly lower in the 300IR group than in the placebo group as was that of each individual rhinitis symptom score. The relative differences from placebo were of −26.3% (Total score), −20.7% (sneezing), −27.7% (rhinorrhea), −21.1% (nasal pruritus) and −34.6% (nasal congestion). These results were consistent to those obtained in the overall population. In a Phase II/III study in subjects with HDM-associated allergic rhinitis, a one year treatment with 300IR sublingual tablets of HDM allergen extracts was found efficacious in the subset of adolescents.