A critical appraisal on AIT in childhood asthma

Allergen immunotherapy (AIT) is the only disease-modifying treatment approved for allergic rhinitis and allergic asthma and represents a suitable therapeutic option, especially in childhood, to modify the progression of respiratory allergic diseases. Starting from the previous "generic class effect" evaluation, as testified by the numerous meta analyses, AIT is now considered a product-specific pathogenic-oriented treatment.

AIT was empirically proposed more than one century ago in the subcutaneous form (SCIT), but the IgE-mediated mechanism of allergy was elucidated only after 50 years of clinical use of the treatment. The sublingual administration (SLIT) was developed during the 1980 ties, to achieve an improvement in safety and convenience. While SCIT is approved in the United States for the treatment of asthmatic patients with more than 12 years, so far few trials evaluated the clinical efficacy and safety of SLIT in children with allergic asthma, although the indications and some aspects remain unclear. Certainly, due to compliance problems, the age below 3 years may be reasonably considered a practical contraindication.

Given that some specific AIT products are effective and approved as drugs (AIFA, EMA, FDA), the use in children is still debated. Some aspects still need robust confirm: (a) the safety of AIT in asthma; (b) the optimal regimen of administration; (c) the role of AIT as preventative treatment for asthma development.