Comparison of the Long-Term Efficacy of Subcutaneous and Sublingual Immunotherapies in Perennial Rhinitis

Abstract

Background: Both sublingual and subcutaneous immunotherapies have a documented clinical efficacy, but only a few comparative studies have been performed. Objectives: To evaluate and compare the long-term efficacies of subcutaneous and sublingual immunotherapy. Methods: One hundred and ninety-three patients with house dust mite allergies, out of an original total of 230, were treated with subcutaneous and sublingual house dust mite-specific immunotherapies for 3 years and also observed for 3 years after discontinuation of the treatment. The patients were randomized into 2 groups: the sublingual group (97 patients) and the subcutaneous group (96 patients). The therapy’s success was evaluated using the symptom score, skin prick test results, and the nasal allergen challenge score. The patients were evaluated at the beginning of the study, at the end of years 1, 2, and 3, and also at the end of the 1st and 3rd years after discontinuation of the specific immunotherapy treatment. Results: Immunotherapy induced a significant improvement during the treatment and the follow-up period. We found a greater improvement in the subcutaneous group compared to the sublingual group when we looked at the comparative results of the total 6 years. Conclusion: We suggest subcutaneous immunotherapy for patients with perennial allergic rhinitis due to the better results that were obtained during our study period. Nevertheless, sublingual immunotherapy is now accepted by WHO as a valid alternative to the subcutaneous route and should be used in all patients who require immunotherapy and do not accept the subcutaneous route of allergen administration.

Current Concepts and Update for Sublingual Immunotherapy

“…These studies were published from 1993 to 2011, with dust mite the most common allergen studied (60 %). The studies all have small number of subjects with the exception of Tahamiler et al [38]. While the majority of these studies find both SLIT and SCIT efficacious, there is no clear agreement among the studies as to which form of treatment is more effective.…”

“…Several published prospective studies have compared the efficacy of sublingual to subcutaneous immunotherapy [32][33][34][35][36][37][38][39][40][41], and these are detailed in Table 1: Prospective Studies of SLIT versus SCIT. These studies were published from 1993 to 2011, with dust mite the most common allergen studied (60 %).…”

Sublingual immunotherapy: current concepts for the U.S. practitioner

“…The comparative effectiveness of SLIT to SCIT continues to be a topic of great interest. Prospective studies of SLIT have not found clear agreement as to which form of treatment is more effective . A recent systematic review of head‐to‐head studies of SLIT and SCIT found low‐grade to moderate‐grade evidence supporting that SCIT is more effective for allergic asthma and allergic rhinoconjunctivitis, but the authors cautioned that more studies are required to strengthen the evidence base …”

Allergic rhinoconjunctivitis: Complementary treatments for the 21st century

“…One study of perennial allergic rhinitis concluded that over a 6-year follow-up period, those treated with subcutaneous therapy fared better than those treated with SLIT in regard to symptom scores, skin prick testing, and nasal allergen challenge scores. They concluded that the sublingual route should be offered as an alternative second-line treatment for those who refuse subcutaneous therapy [35]. Others suggest that SLIT provides notable improvements in symptoms [36,37•], improves quality of life [38], and reduces medication use in adults and children [37•,39]; thus, they argue that it is a revolutionary addition to immunotherapy.…”