Double-blind, placebo-controlled study with sublingual immunotherapy in children with seasonal allergic rhinitis to grass pollen.

UNLABELLED: Sublingual immunotherapy (SLIT) has been recognized as a viable alternative to subcutaneous immunotherapy for respiratory allergies both in adults and children, but clinical documentation about safety and efficacy in children is still poor. The purpose of this study was to assess the efficacy and tolerance of SLIT in children who are sensitized to grass pollen. METHODS: Children with a clinical history of intermittent rhinoconjunctivitis, with or without mild asthma and positive skin prick tests to grass pollen, were selected to participate in a 2-year double-blind, placebo-controlled study with SLIT, using a grass extract (ALK-Abellò). RESULTS: 22 children were analyzed at the end of the study. No relevant side effects occurred in the active group. A statistically significant difference (p = 0.05; Mann-Whitney test) in favor of the active group (n = 10) could be shown for drug consumption during the second year, as well as a significant improvement as compared to the first year of SLIT (p = 0.05; Wilcoxon test). CONCLUSIONS: Despite the small number of patients, our data suggest that SLIT with a grass pollen extract is well tolerated in children and is able to significantly reduce drug consumption during the second year of treatment. Studies in larger groups of children sensitized to both grass and tree pollens are needed to definitively assess the role of SLIT in intermittent, seasonal rhinitis and pollen asthma.