House Dust Mite-Associated Allergic Rhinitis: Efficacy of STG320 Sublingual Tablets of House Dust Mite Allergen Extracts
Saturday, March 5, 2016
South Exhibit Hall H (Convention Center)
Michel Roux, MD, Hélène Nguyen, PharmD, Agnès Viatte, Robert K. Zeldin, MD
Rationale: Efficacy of STG320 house dust mite (HDM) sublingual tablets has been demonstrated. Here we report the efficacy on rhinitis symptoms in two DBPC studies.

Methods: Adults with HDM-associated allergic rhinitis were enrolled in a natural field study (NatField) and an environmental exposure chamber study (EEC). In the former, subjects received STG320 500IR or 300IR, or placebo once daily for 1 year. In the latter, subjects received 500IR, 300IR or 100IR of STG320 or placebo, daily during 6 months. In NatField, the Average Rhinitis Total Symptom Score (ARTSS) and individual rhinitis symptom scores (sneezing, rhinorrhea, nasal pruritus, nasal congestion) were assessed over the last 3 months of treatment. In EEC, the changes from baseline to end-of-6-month-treatment in ARTSS (ChBLARTSS) and individual symptoms were assessed over the 4 hours and the last 2 hours of the HDM challenges.

Results: In NatField (N=509), ARTSS Least-Square means were significantly reduced (p<0.05) with relative differences from placebo of -17.4% (500IR) and -18.5% (300IR). In the active groups, the scores for all symptoms were lower than placebo, with significance at both doses for sneezing and nasal pruritus, and at 300IR for nasal congestion. In EEC (N=355), relative differences from placebo increased from 17.5% (100IR) to 25.8% (300IR) and 31.1% (500IR) for ChBLARTSS0-4h, and 31.3% (100IR) to 42.3% (300IR) and 44.7% (500IR) for ChBLARTSS2-4h. The changes from baseline to the end-of-6-month-treatment in individual scores also improved with the increase in dose.

Conclusions: The 300IR dose of STG320 was effective for the treatment of symptoms of HDM allergic rhinitis subjects.