Treatment with STG320 Sublingual Tablets of House Dust Mite Allergen Extracts: Profile of Subjects with HDM-Associated Allergic Rhinitis in the Clinical Development Program

Rationale: Efficacy and safety of STG320 house dust mite (HDM) sublingual tablets for the treatment of HDM-associated allergic rhinitis (AR) have been assessed in 7 DBPC clinical trials. The clinical profile of all enrolled subjects is presented here.

Methods: Across studies subjects (5-64 years) with HDM-associated AR for at least one or two years were randomized to receive placebo or STG320 at doses from 100IR to 1,500IR. The diagnosis of HDM-related allergy was confirmed by a positive skin prick test (EU, Canada) or nasal provocation test (Japan) and positive HDM-specific IgE. Data on demographics, disease characteristics, sensitization and asthma status were collected and analyzed descriptively.

Results: A total of 2,407 subjects received the study treatment. Of them, 1,571 (1,182 adults, 261 adolescents and 128 children) received at least one dose of STG320 and 836 (536 adults, 182 adolescents and 118 children) received placebo. Subjects (50% female) averaged 26 years of age and were mainly Caucasian (50%) or Asian (45%). At randomization, 61% of actively-treated subjects and 58% of placebo-recipients were polysensitized; 25% (active) and 29% (placebo) had asthma. 70% and 81% of subjects in the active and placebo groups, respectively, were treated for at least 6 months. The maximum treatment duration was 427 days.

Conclusions: To date, a substantial number of subjects with HDM allergic rhinitis have participated in the STG320 clinical program. A Phase III study has been initiated to further assess the efficacy and safety of this therapy.