RWD Analyses on AIT Long-Term Effects
In contrast to symptomatic medication, AIT is the only causal treatment option for IgE-mediated allergic diseases and therefore has the potential for long-term effects that last after termination of therapy (1,2). There are a few RCTs showing long-term efficacy for single SCIT and SLIT preparations in allergic rhinitis (37–42) for up to five years after terminating three years of AIT. In children, one of these trials additionally showed a reduced risk of experiencing asthma symptoms or using asthma medication while there was no difference in time to onset of asthma during the two-year follow-up period (41). Data from different real-world settings e.g. non-interventional studies or analyses in claims databases, patients surveys, electronic health records or product and disease registries allow to analyze the effectiveness and medication adherence under practical conditions (10,43) and the evaluation of long-term data for larger patient populations and even longer follow-up periods without the risk of ethical concerns arising from withholding a therapy proven to be effective in placebo groups in 5-years’ DBPC AIT studies.
This review summarizes results from thirteen publications dealing with retrospective cohort assessments of national prescription databases in Europe. All nine assessments investigating effectiveness consistently showed long-term effectiveness for AIT in allergic rhinitis for different time periods; long-term effectiveness for AIT in asthma as well as the asthma preventive effect was proven in most studies (15–19,21,22,25,26). Therefore, the findings from the RWD summarized here are in line with those observed in RCTs showing long-term effectiveness of AIT in allergic rhinitis and asthma as well as asthma preventive effects (37–42). Since national and international allergology societies (1,2,44) demand an individual product-based efficacy evaluation respective long-term RWD for more individual AIT preparations are desirable.