Allergen immunotherapy: what is the added value of real-world evidence from retrospective claims database studies?

Allergen immunotherapy (AIT) is the only disease-modifying treatment available for allergic rhinitis. It works by inducing allergen-specific immune tolerance and by preventing the development of new allergen sensitization. Studies have shown that AIT has proven long-term efficacy in people with allergic rhinitis, however there is a lack of studies of real-world evidence.

In this review, retrospective studies from France and Germany have confirmed the sustained benefits of grass and pollen AIT. When compared to standard of care, AIT improved allergic rhinitis symptom control after treatment cessation (reduced allergic rhinitis symptomatic medication use), as well as asthma control and decreased the risk of developing asthma.

Real-world evidence studies have advantages over randomizes clinical trials, such as evaluation of a broader patient population that mirrors clinical practice, greater generalizability and enabling the assessment of long-term safety and effectiveness. In particular real-world evidence of AIT in people with allergic rhinitis and asthma confirm and build on the efficacy findings of regular studies, and their results can be used to guide clinical management and assist counselling of patients, so much so that recent guidance supports the inclusion of real-world evidence data in updated guidelines.