Dermatophagoides farinae allergen encapsule for oral immunotherapy with HDM allergic rhinitis

Abstract

It is well known that the house dust mites (HDMs) are the most common and potent inhalant allergens world-wide and the allergen immunotherapy (AIT) can efficaciously and safely ameliorate the allergic symptoms. Different formulations and routes of HDMs AIT have been achieved symptomatic improvement with mite allergic rhinitis (AR) and/or asthma. The object of the present article is to observe the efficacy and safety of oral immunotherapy (OIT) by enteric-coated capsules (EC) of Dermatophagoides farinae allergen (Df) with mite AR. A year of single blind placebo trial was applied. A total of 54 AR patients aged 25.8 in average with/without asthma and skin prick test (SPT) positive in HDMs were selected into either active or placebo groups. The OIT started with 5 days of dose rush induction, succeeded by a maintenance dose for 12 months. The efficacy of the treatment was assessed by symptomatic evaluation and laboratory in vivo and in vitro parameters of pre-immunotherapy (pre-IT) and post-immunotherapy (post-IT) statistically. The patients each received a total accumulative dose of 16 715BU Df protein nitrogen, and 87.5% (21/24) subjects achieved symptomatic improvement. The post-IT symptom scores decreased (t=11.07, P<0.001); visual analog scale (VAS) decreased (t=10.68, P<0.001); number of patients required symptom-medication decreased from 23/24 to 3/24 cases (c2=33.57, P<0.001); SPT wheal sizes of both Df and Dp significantly reduced (Df t=2.64, P=0.015 and Dp t=6.01, P<0.001); nasal provocation test (NPT) with the antigen tolerance elevated more than 3 times (c2=9.65, P=0.008). The only unchanged parameter was the tIgE levels (P=0.07). The parameters of placebo group were changed but not significant statistically or negligible. There were no local or general adverse reactions in both groups happened in the one year course of OIT. It is concluded that the newly designed formulation and route of clinical administration by Df EC OIT with AR were comparable to that of Df sublingual IT. The new formulation is more convenient and promising approach to treat AR.

Oral immunotherapy with enteric-coated capsules for allergic rhinitis caused by house dust mites

“…A study has shown that short-term OIT is effective for cedar pollinosis in a Japanese population ( 18 ). Our previous single blind placebo-controlled study has also confirmed that OIT based on enteric-coated capsules is effective for AR caused by Df ( 19 ). Enteric-coated capsules are solid dosage forms, which are designed to bypass the stomach and release the drug in the small intestine, and protect the integrity of the Df from the acid in the stomach.…”

Prevalence, causes and treatments of allergic rhinitis in Malaysia: a literature review

“…Immune-based therapies for specific allergens have shown promising results in averting the symptoms of allergic rhinitis [99]. In a single blind, randomized placebo-controlled trial, HDM-sensitized Chinese AR patients showed significant reductions in their mite sensitivities after oral consumption of encapsulated D. farinae allergen extract [100]. Fujisawa et al (2018) also emphasized that subcutaneous injection of allergen mixture solution at appropriate doses provided longterm safety and efficacy among Japanese patients with HDM-induced AR [101].…”