Patients treated with SLIT vs. SCIT showed similar outcomes

ORLANDO, Fla. — Sublingual immunotherapy compared with traditional subcutaneous immunotherapy resulted in comparable results, according to data presented at the 2012 Annual Meeting of the American Academy of Allergy, Asthma and Immunology.

Subcutaneous immunotherapy (SCIT) has been effective in stimulating prolonged remission of allergic rhinitis, but has been implicated in association with allergic side effects. In previous studies, an alternative strategy using sublingual immunotherapy (SLIT) has demonstrated an approximate 30% reduction in symptom scores and a 40% reduction in medication use during the summer months.

Stephen R. Durham

To investigate the long-term effects of SLIT as a beneficial alternative to SCIT — whether SLIT induces tolerance and by what mechanism — Stephen R. Durham, MA, MD, and colleagues compared approaches in patients with severe hay fever using SCIT as a positive control. In a double-blind, placebo-controlled, double-dummy study, lasting 1 year, the investigators enrolled 50 patients to compare SLIT with placebo and SCIT with placebo, with a special focus on the comparison between SLIT and placebo. In this small study, researchers found that similar effects were produced from both approaches.

Durham also discussed a larger trial — Gauging Responses in Allergic Rhinitis to SCIT vs. SLIT (GRASS) — still underway at Royal Brompton Hospital and Imperial College in London. Researchers there are testing whether sublingual immunotherapy induces suppression of allergen-induced early and late-phase nasal responses that persist for at least 1 year after discontinuation of treatment. Participants in the study will receive treatment over a 2-year period followed by a 1-year blinded withdrawal phase.

At the conclusion of the study, nasal fluid and samples of peripheral blood for T cell and B-cell assays will be analyzed at corresponding time periods, and nasal biopsies will be collected at the end of the withdrawal phase.

References:

• Durham SR. Course 1204. Subcutaneous vs. sublingual immunotherapy for aeroallergens. Presented at: the 2012 AAAAI Annual Meeting; March 2-6, 2012; Orlando.