RANDOMIZED CONTROLLED TRIAL OF LOCAL ALLERGOID IMMUNOTHERAPY ON ALLERGIC INFLAMMATION IN MITE-INDUCED RHINOCONJUNCTIVITIS

Background Non-injective routes of immunotherapy are thought to be val uable therapeutic options for respiratory allergy. We investigated the clinical efficacy and the effects of sublingual/oral immunotherapy on conjunctival allergic inflammation in patients with mite-induced resp iratory allergy. Methods We used a double-blind placebo-controlled des ign. 20 patients with mite-induced rhinoconjunctivitis (six of whom al so had mild asthma) were randomly assigned sublingual/oral immunothera py (n=10) or placebo (n=10) for 2 years. We assessed symptom score by diary cards and inflammatory-cell infiltrate, and expression of interc ellular adhesion molecule 1 (ICAM-1) in the conjunctiva after specific allergen challenge at enrolment and after 12 and 24 months of treatme nt. Findings We found significantly lower symptom scores in the immuno therapy group than in the placebo group in most of the winter months ( p=0.05). Compared with the placebo group, inflammatory-cell infiltrati on after conjunctival challenge, and ICAM-1 expression on conjunctival epithelium decreased significantly in the first year of treatment in the immunotherapy group (p=0.04 and p=0.02, respectively). These effec ts were also seen for the minimum persistent inflammation, in symptom- free patients exposed constantly to allergens (p=0.02). Serum concentr ations of eosinophil cationic protein decreased significantly (p=0.04) . Immunotherapy was well tolerated and compliance was good. Interpreta tion Our results suggest that this immunotherapy is clinically effecti ve in rhinoconjunctivitis and that it decreases the immune-mediated in flammatory responses to the allergen.