Oral and Sublingual Immunotherapy

Abstract

Subcutaneous immunotherapy is the only disease-modifying treatment for allergic rhinitis and asthma. Unfortunately, it is not accessible or appropriate for all patients, for reasons such as the risks of treatment, time commitment and cost involved, poor access to subspecialty care, and even the fear of injections. In the case of food allergy, treatments are inaccessible simply because they do not exist. Oral and sublingual immunotherapies offer superior safety when compared to allergy shots. The ease of administration, in particular with sublingual immunotherapy, and the ability to dose at home make these modalities very attractive. Aeroallergen sublingual immunotherapy has been used extensively in Europe for more than 10 years, but is not approved in the United States, despite various studies demonstrating its safety and efficacy. Recent studies have focused on addressing continuing concerns, such as determining the ideal dose and protocol, the therapy’s effect in polysensitized patients, its safety in more severe patients, and its long-term effects. As each of these concerns is addressed, it seems more likely that sublingual immunotherapy will be added to the arsenal of treatments available to US allergists. Both oral and sublingual immunotherapies have been studied for food allergy, with preliminary evidence suggesting the ability of these treatments to induce desensitization. Recent studies, including the Burks study reviewed in this manuscript, suggest the potential for tolerance induction. However, there has been ongoing debate on how tolerance should be defined and measured. In addition, questions remain about the short-term and long-term safety of the treatment. Until these questions can be addressed with larger controlled studies, these oral and sublingual immunotherapies should not be considered ready for clinical use for food allergy.