Comparative Real World Effectiveness of SQ Sublingual Immunotherapy (SLIT)-Tablets vs. Controls in Allergic Rhinitis and Asthma

Study Overview
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Brief Summary
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To assess the impact of SQ SLIT-tablets (SQ Grass SLIT-tablet and SQ HDM SLIT-tablet) in Danish and Swedish allergic rhinitis (AR) patients, with or without asthma, between 2007-2020.

Detailed Description
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Allergic rhinitis (AR) is an inflammatory disorder, characterised by pruritus, sneezing, rhinorrhoea, and nasal congestion. It is one of the most common disorders worldwide, with an estimated global prevalence of 10-30%. AR is a chronic and progressive disease, as the underlying respiratory allergy can progress into allergic asthma. The prevalence of asthma in patients with AR is high and estimated between 10-40%. The presence of AR commonly exacerbates asthma, increasing the risk of asthma exacerbations, emergency visits and hospitalisations for asthma. Recently, the high-quality retrospective cohort REACT study (ClinicalTrial.gov: NCT04125888) found that allergy immunotherapy (AIT) was associated with long-term reduction in AR medication use as well as significant reductions in both controller and reliever asthma medication and concurrent lower risk of asthma exacerbation and pneumonia in subjects with pre-existing asthma. The SQ sublingual immunotherapy (SLIT)-tablets have robust evidence from randomised controlled trials (RCTs), but real-world evidence (RWE) is needed to complement the findings from RCTs by looking at e.g. longer time horizons and broader patient populations. As the REACT study was not designed to specifically look at evidence-based AIT treatments like the SQ SLIT-tablets, the real-world effectiveness of SQ SLIT tablets remain to be further elucidated.

Official Title
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Comparative Real World Effectiveness of SQ Sublingual Immunotherapy (SLIT)-Tablets vs. Controls in Allergic Rhinitis and Asthma - Outcomes From a Multinational Register Study

Conditions
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Allergy, Allergic Rhinitis, Asthma

Intervention / Treatment
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* Drug: SQ SLIT-tablet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: AR-patients identified by dispensations of prescribed AR medications and/or ICD10-codes of AR in specialty care For the SQ SLIT-tablet cohort: - at least 2 dispensings within 365 days of SQ SLIT-tablets (ATC: V01AA02 and V01AA03) For the control cohort: - unexposed subjects will be identified from the study population of AR-patients that may be eligible to receive SQ SLIT-tablets, but have not dispensed a prescription of SQ SLIT-tablets during the index year of the case or prior to that year Exclusion Criteria: - allergy immunotherapy treatment with grass or HDM allergens prior to the index event

Ages Eligible for Study
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Minimum Age: 5 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Allergic rhinitis patients with and without asthma treated with SQ SLIT-tablet<br> | Drug: SQ SLIT-tablet<br>* SQ grass SLIT-tablet and/or SQ house dust mite SLIT-tablet<br>|
| Allergic rhinitis patients with and without asthma not treated with SQ SLIT-tablet<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Symptom-relieving medication use for allergic rhinitis | Overall number of prescriptions and by individual drug classes | From pre-index to follow-up year(s), assessed from 2005 and up to 2021 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Medication use for asthma | Overall number of prescriptions and by individual drug classes | From pre-index to follow-up year(s), assessed from 2005 and up to 2021 | 
| Asthma disease severity assessed by reliever and controller medication prescriptions and hospitalisations due to asthma |  | From pre-index to follow-up year(s), assessed from 2005 and up to 2021 | 
| Lower airway infections assessed by prescriptions of antibiotics and diagnosis codes for pneumonia |  | From pre-index to follow-up year(s), assessed from 2005 and up to 2021 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Allergy immunotherapy, Sublingual immunotherapy (SLIT)-tablets, Grass, House dust mite, Retrospective cohort study