Résumé
Background: Allergen immunotherapy is indicated in allergic rhinitis (AR) patients not well controlled by pharmacotherapy and avoidance or who wish to reduce the long-term use of rescue medications (RM) such as corticosteroids (CS) and possible adverse effects. In a large randomised, DBPC Phase III trial, the 300IR house dust mite (HDM) sublingual tablet was found effective in reducing the use of RM in all evaluable patients aged 12–65 with HDM-AR 1,2 . Here, we focus on the efficacy and steroid sparing effect in the subset of patients who used CS at study entry.Method: Eligible patients with medically confirmed HDM-AR received the 300IR HDM tablet or placebo once daily for one year. To manage severe/intolerable symptoms, participants were allowed to use antihistamines, intranasal or oral CS (INCS or OCS) according to a stepwise regimen. Based on their symptom severity and RM use records, 2 balanced scores were analysed by ANCOVA to assess the treatment effect during 4 weeks at the end of treatment (primary period): EAACI-recommended Combined Symptom and Medication Score (CSMS 0–6) and Total Combined Rhinitis Score (TCRS 0–24 ). Those pre-defined and post hoc endpoints, respectively, and the proportion of patients using RM, overall and by RM category, were analysed in all patients and in those who used INCS and/or OCS at entry.Results: During the primary period, both combined scores were significantly lower in the 300IR group than in the placebo group (p ≤ 0.0002) in evaluable patients, overall (300IR = 586, placebo = 676) and in INCS/OCS-using subset (300IR = 373, placebo = 396). Absolute differences from placebo for all patients vs the INCS/OCS-using subset in average CSMS 0–6 were −0.26, CI 95% [−0.38; −0.14] vs −0.32, CI 95% [−0.49; −0.15] and in TCRS0–24 −1.07, CI 95% [−1.35; −0.79] vs −1.33, CI 95% [−2.03; −0.62], respectively. In the INCS/OCS-using subset, 54% of patients in the 300IR group vs. 42% in the placebo group were able to discontinue CS completely by the end of the treatment (p = 0.0007). However, the results were mainly driven by INCS as only about 10% patients in both groups used OCS.Conclusion: In HDM-AR patients, 300IR HDM sublingual tablet has a steroid sparing effect while concomitantly and significantly reducing symptoms, especially in severe patients requiring corticosteroids.References : 1. Demoly et al. JACI 2021;147:1020–30.2. Pfaar et al. Allergy 2020;75(S109):100–19