Real-world evidence for the long-term effect of allergen immunotherapy:
current status on database-derived studies
Abstract
Background: Randomized controlled trials (RCTs) are the
gold-standard for benefit-risk assessments during drug approval
processes. Real-word data (RWD) and the resulting real-world evidence
(RWE) are becoming increasingly important for assessing the
effectiveness of drug products after marketing authorization showing how
RCT results are transferred into real life care. The effectiveness of
allergen immunotherapy (AIT) has been assessed in several RWE studies
based on large prescription databases. Methods: We performed a
literature search for retrospective cohort assessments of prescription
databases in Europe to provide an overview on the methodology, long-term
effectiveness outcomes and adherence to AIT. Results: 13
respective publications were selected. AIT was more effective in
reducing the progression of allergic rhinitis (AR) compared to a non-AIT
control group receiving only symptomatic treatment for AR for up to 6
years. The development and progression of asthma was hampered for most
endpoints in patients treated with most preparations compared to the
non-AIT group, receiving only anti-asthmatic medication. The results for
“time to onset” of asthma were inconsistent. Adherence to AIT
decreased during the recommended 3-years treatment period, however in
most studies higher adherence to subcutaneous than to sublingual AIT was
shown. Conclusion: The analysis of long-term effectiveness
outcomes of the RWE studies based on prescription databases confirms the
long-term efficacy of AIT demonstrated in RCTs. Progression of rhinitis
and asthma symptoms as well as delayed onset of asthma triggered by
different allergens, real life adherence to the treatment shows
differences in particular application routes.