Safety Of The 300 IR and 500 IR Doses Of A House Dust Mite Allergen Extracts Sublingual Tablet In Adults with Allergic Rhinitis

Rationale: The efficacy of two doses (300IR and 500IR) of house dust mite (HDM) sublingual tablets was demonstrated in a randomized, DBPC study in patients with HDM-associated allergic rhinitis. Here we present the safety of this treatment.
Methods: Adults (18-50 years) with medically confirmed HDM-associated allergic rhinitis for at least one year were randomized to receive 300IR or 500IR HDM tablet or placebo once daily for one year and were followed for the subsequent year. Adverse events (AE) were monitored throughout the study and analyzed descriptively. All patients who received at least one dose of the investigational product were included in the safety set.
Results: 509 patients (300IR=170, 500IR=169, Placebo=170) were randomized and received at least one dose. 88% (300IR), 83% (500IR) and 80% (Placebo) reported at least one AE on treatment (TEAE). The most common TEAEs reported in the active groups were mild or moderate application site reactions i.e., oral pruritus (25-30% of patients), throat irritation (21-24%) and mouth edema (12-17%), which mostly occurred within the first month of treatment. Nine participants experienced serious TEAEs of which 4 were considered drug-related: pharyngeal edema (300IR), eczema (300IR), moderate respiratory distress related to a sublingual edema (500IR), and urticaria (Placebo); all recovered. Forty-two patients (300IR=17, 500IR=20, and Placebo=5) withdrew from the study due to a TEAE, most commonly pharyngeal edema, dyspepsia, nausea and mouth edema.
Conclusions: Treatment with HDM sublingual tablets at doses of 300IR and 500IR was associated with a favorable safety profile. There was no appreciable difference in tolerability between the tested doses.