Grass pollen sublingual immunotherapy: a double-blind, placebo-controlled study in elderly patients with seasonal allergic rhinitis

Abstract

Background: This study evaluates the safety and efficacy of specific sublingual immunotherapy (SLIT) against grass pollen allergens in patients >60 years of age with seasonal allergic rhinitis (SAR) and/or asthma. This study sought to assess nasal symptoms during the grass pollen season, reduce medication use, and monitor adverse reactions during immunotherapy.

Methods: Seventy-eight 60- to 70-year-old patients with SAR and a confirmed grass pollen allergy according to skin-prick tests, nasal provocation, and measurement of serum IgE were included in the study. The patients were individually randomized to the active or placebo groups using a double-blind method. A total of 41 subjects in the SLIT group (5 grass pollen mixture) and 37 subjects in the placebo group were monitored for 3 years. The patients were required to record each use of an antiallergy medication on a diary card.

Results: Thirty-eight patients completed 3 years (preseasonal) of SLIT, and 34 subjects finished the placebo treatment in the same time period. The total nasal symptom score decreased by 64% in the active group and 7% in the placebo group after SLIT. This difference was only significant in the active group (p < 0.05). At the end of therapy, the total medication score of the active group decreased significantly by a maximum of 51% (p < 0.05), whereas the total medication score of the placebo group had an insignificant decrease. None of the study participants had systemic adverse reactions during the study period.

Conclusions: SLIT in elderly patients with a grass pollen allergy generated a significant clinical improvement in the active group compared with the placebo group for grass pollen season. This therapy was well tolerated.