Allergen Immunotherapy Clinical Trial Outcomes and Design: Working Toward Harmonization of Methods and Principles

Progress has been made in the harmonization of efficacy and safety outcome measures for allergen immunotherapy (AIT) trials, but unresolved issues still remain. Furthermore, there are discrepancies in recommendations from professional medical societies and regulatory agencies regarding requirements for AIT trials. In this article, we reviewed published recommendations and current data from recent clinical trials, as well as the criteria applied by regulatory authorities for approval of AIT products, to provide updated considerations for conducting phase 3 AIT trials. Topics discussed include analysis of outcomes and trial designs for pediatric and asthma indications, as well as trial designs for perennial allergic rhinoconjunctivitis. In addition, the need for harmonization of safety reporting is emphasized. Considerations presented in this article may further effort to find common ground among professional medical societies and government agencies in developing future recommendations for AIT trial design.