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.