Immunotherapy for allergies and asthma: present and future

Abstract

Allergen immunotherapy (IT) is a proven approach for treating allergic rhinitis and allergic asthma that has been practiced since 1911 and has undergone significant development in the past two decades. As currently practiced, IT involves subcutaneous or sublingual administration of allergens, both methods of which have been extensively investigated. In addition to allergen IT, a number of additional nonspecific IT approaches are being used or are in phase II/phase III clinical trials, which may be available in clinics within the next one to three years. Such therapies include anti-IgE antibodies and the soluble IL-4 receptor. Other experimental IT approaches are at the preclinical research stage and may proceed to clinical trials and the clinic within the next five to ten years. This review discusses the pros and cons of recent developments in both currently practiced and experimental IT approaches.

Figure 1

Mechanism underlying allergic diseases (adapted from Steve Holgate, JACI 2006). In principle, allergens induce an immunologic response via APC-T cell interactions leading to the production of specific cytokines, which in turn help B cells produce IgE antibodies. Each of these steps can potentially be targeted for therapeutic intervention.