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.
Keywords: allergic rhinitis, allergic asthma, allergen
immunotherapy, long-term efficacy, real-world evidence