Efficacy of sublingual immunotherapy with high-dose mite extracts in asthma: A multi-center, double-blind, randomized, and placebo-controlled study in Taiwan

Abstract

Sublingual immunotherapy (SLIT) has been recommended as a viable alternative to subcutaneous injection therapy in the treatment of airway allergies, though more data is needed from well-controlled studies for documenting its efficacy in different ethnic populations. Ninety-seven children (age range 6-12 years), mild-to-moderate asthma with a single sensitization to mite allergen, were enrolled from 5 medical centers in Taiwan to evaluate the efficacy and safety of SLIT with standardized mite extracts, which contain Dermatophagoides pteronyssinus (D.p.) and Dermatophagoides farinae (D.f.). Patients were double blinded and randomly assigned to either a SLIT or placebo group. Following 24 weeks of study period, symptom and medication scores, lung function tests, skin prick tests, total serum IgE, and specific IgE to D.p. and D.f. were recorded. The results showed that there was statistically significant difference between these two groups in the analysis of daily (P=0.011), nighttime (P=0.028), and daytime (P=0.009) asthmatic scores after 24 weeks of treatment. Patients receiving SLIT improved their forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), and peak expiratory flow (PEF) as compared to baseline (P=0.042, P=0.048, and P=0.001, respectively). No differences were found in skin prick test, total serum IgE and specific IgE to D.p. and D.f. Tolerance with high-dose SLIT was good with few minor adverse events reported. Our results indicated that a 24-week SLIT is of clinical benefit to mite-sensitive asthmatic children in Taiwan.

Allergen-Specific Immunotherapy for Pediatric Asthma and Rhinoconjunctivitis: A Systematic Review

“…[22][23][24][32][33][34][35]37,38 Seven studies evaluated dust mite allergen. [22][23][24][32][33][34]38 The SLIT-treated children in the placebo-controlled studies demonstrated moderate to strong improvement in asthma symptoms. The risk of bias was low in 3 studies.…”

“…[22][23][24][25][26][27][28][29]32,33,[35][36][37] Six studies evaluated dust mite allergen. [22][23][24][25][26]32 The placebo-controlled studies demonstrated significant reductions in medication use in the SLIT group relative to the placebo group, with moderate to strong magnitudes of effect in patients with asthma and/or rhinitis. The magnitudes of effect could not be determined in 7 studies.…”

Chinese Guideline on allergen immunotherapy for allergic rhinitis

“…In one of the studies, a subsequent post hoc analysis by asthma severity revealed significant clinical benefit in the AIT group with moderate, persistent asthma at baseline with 401-800 μg budesonide/day; with greater achievement of well-control asthma and totally controlled asthma (236). In another study, global assessment of asthmatic symptom by patient and physician, the primary outcome measure, was improved after ASIT but not placebo treatment (233).…”

“…The efficacy of AIT in asthma is measured using symptom scores, medication scores, as well as lung function test (55,134,(233)(234)(235). The symptom and medication scores are frequently used as primary endpoints in AIT trials.…”

“…The parameters included FEV 1 % predicted, PEF rate in the morning and night, PEF% predicted value as well as brochoprovocation tests (54,55,(233)(234)(235)237). However, within-group analysis in some studies failed to demonstrate significant differences between AIT and control groups (233,234,236).…”