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

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.

CONCLUSIONS

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.