Allergen Immunotherapy: Current State and Ways Forward

Diego Bagnasco, Matteo Ferrando, Elisa Testino, Annamaria Riccio, Giorgio Walter Canonica and Giovanni Passalacqua

Allergen specific Immunotherapy (AIT), introduced more than one century ago, is the only allergen-oriented biological response modifier that redirects in a complex way the mode of response to antigens of the immune system. The traditional route of administration had remained for decades the subcutaneous one. In the last 30 years the sublingual administration was introduced and accepted. Nowadays, there are numerous large regulatory trials (mainly with sublingual tablets) confirming the efficacy and safety of this route for the more relevant allergens. The efficacy and safety of sublingual AIT was also consistently demonstrated in asthma, and the treatment is now included as possible adjunct in asthma guidelines. Obviously, a proper standardization of the products is mandatory. The component resolved diagnosis approach, allowed to better refine the prescription and the selection of candidate patients for AIT. In the next future, new administration routes are expected (epicutaneous, intralymphatic), together with the use of adjuvants. Also, the role of oral or sublingual desensitization for food allergy is currently emerging.