House dust mite subcutaneous immunotherapy has sustained long-term effectiveness on allergic rhinitis and asthma: A 10-year follow-up

Abstract

Background: Maintenance doses for allergen immunotherapy (AIT) have been recommended for at least 3 years but little data on long-term efficacy is available depending on AIT duration. To show sustained efficacy 10 years after completion of treatment with depigmented-polymerized house dust mite (dpg-pol HDM) allergen extract in adults with asthma and/or rhinoconjunctivitis. Methods: Patients included in a double-blind placebo-controlled AIT study with dpg-pol HDM allergen extract were reviewed at completion of the perennial treatment and 10-year follow-up (10y-FU). Change in symptom and rescue medication score was the primary objective. Visual analog scale (VAS), asthma control test (ACT), and degree of disease control were the secondary objectives. A comparative analysis between patients who underwent AIT treatment for <3 years and ≥3 years was performed. Results: Data from 31 patients (mean age 38 years) were available at 10y-FU. All had asthma and 29 had rhinoconjunctivitis at baseline. Twenty-three patients were treated ≥3 years and 8 for <3 years. Seventeen (55%) patients were asymptomatic at completion of AIT, with significant differences for nasal, conjunctival, and bronchial symptoms (p