Steroid Sparing Effect of 300IR House Dust Mite Sublingual Immunotherapy Tablet in Mite Allergic Rhinitis

In a large randomized controlled trial (NCT02443805) in moderate-to-severe house dust mite (HDM) allergic rhinitis (AR) patients with/without controlled asthma, the 300IR HDM sublingual immunotherapy (SLIT) tablet confirmed its efficacy in reducing symptoms and rescue medication (RM) use. This post hoc analysis aimed at assessing the potential steroid sparing effect of this tablet.

Participants receiving 300IR HDM SLIT-tablet or placebo for ∼12 months could use antihistamines (AH1), corticosteroids (CS - intranasal (INCS), or oral (OCS)) in a stepwise manner for subjective intolerable nasal/ocular symptoms. The proportions of patients and days with RM intake (overall and by drug class) were assessed over time and compared between groups (Chi-squared or Wilcoxon rank-sum tests). An odds that is, ratio of probability of using CS/probability of not using CS was calculated. Mean weekly CS doses were analyzed by ANCOVA.

Of 1262 evaluable patients, ∼60% used at least one CS at baseline: 300IR = 373 and placebo = 396. During treatment, the proportions of patients using RM, oral AH1, and CS and of days with RM use decreased in both groups, systematically in favor of 300IR (p < 0.05 at end-of-treatment). Odds results indicated SLIT-patients were more likely not to use CS, whereas placebo-patients were more likely to use CS (p < 0.05 at end-of-treatment). After 12 months, 54% SLIT-patients were able to discontinue CS completely versus 42% placebo-patients (p = 0.0007). Those who were still using CS were taking fewer and lower doses than placebo-patients.

In moderate to severe HDM-AR patients, the 300IR HDM SLIT-tablet showed a steroid sparing effect.