In this study, 115 short ragweed pollen-sensitive subjects, ages 19-50 with a history of allergic rhinitis, were randomized into three treatment arms. Efficacy was evaluated using reduction in average daily rhinoconjunctivitis symptoms and anti-allergy medication scores in the treatment groups compared to the placebo group.
In the active treatment arms, a dose-dependent treatment effect was evident. The medium-dose group achieved a treatment effect of 0.54, and the high-dose group, 0.81, for reduction in rhinoconjunctivitis symptoms. Use of anti-allergy medication during the ragweed pollen season was also reduced in both treatment groups, with a significant effect in the high-dose group.
The actively treated groups also showed an increase in ragweed-specific serum IgG, IgG4 and IgA antibody responses after treatment, but the placebo group did not. No serious adverse events were attributed to sublingual-oral immunotherapy, and overall compliance to the treatment regimen was greater than 85%.