Clinical and immunologic effects of a rush sublingual immunotherapy to Parietaria species: A double-blind, placebo-controlled trial

Abstract

Background: The local (noninjection) routes of immunotherapy are presently regarded as viable therapeutic options for respiratory allergy, and their mechanisms of action are currently undergoing investigation.

Objective: We evaluated the clinical efficacy of a preseasonal rush sublingual-swallow immunotherapy and its effects on allergic inflammation in patients with seasonal rhinoconjunctivitis caused by Parietaria species.

Methods: Thirty patients with Parietaria species-induced rhinoconjunctivitis (13 with mild intermittent asthma) were randomly assigned sublingual-swallow immunotherapy or placebo in a rush preseasonal course. We assessed the seasonal symptom-drug intake score by diary card and the inflammatory infiltration and the intercellular adhesion molecule 1 expression on nasal epithelium after specific allergenic challenge before and after treatment.

Results: The investigated immunotherapy was well tolerated, and no side effects were recorded. A significant reduction of the symptom score (P =.016) and drug intake score (P =. 008) after immunotherapy was observed only in the active group. A decrease of the cumulative score was observed also in the placebo group (P =.046), but the significance was clearly higher (P =.006) in the active group. In the active group a reduction of neutrophils (P =.001), eosinophils (P =.01), and intercellular adhesion molecule 1 expression (P =.04) after specific nasal challenge was also detected.

Conclusion: The present results suggest that this sublingual-swallow immunotherapy administered through a rush schedule is clinically effective and safe and that it decreases the immune-mediated inflammatory responses to the allergen.