Long-term real-world effectiveness of allergy immunotherapy in patients with allergic rhinitis and asthma: Results from the REACT study, a retrospective cohort study

Benedikt Fritzsching; Marco Contoli; Celeste Porsbjerg; Sarah Buchs; Julie Rask Larsen; Lisa Elliott; Mercedes Romano Rodriguez; Nick Freemantle

doi:10.1016/j.lanepe.2021.100275

Long-term real-world effectiveness of allergy immunotherapy in patients with allergic rhinitis and asthma: Results from the REACT study, a retrospective cohort study

Lancet Reg Health Eur. 2021 Nov 30:13:100275. doi: 10.1016/j.lanepe.2021.100275. eCollection 2022 Feb.

Authors

Benedikt Fritzsching¹, Marco Contoli², Celeste Porsbjerg³, Sarah Buchs⁴, Julie Rask Larsen⁵, Lisa Elliott⁴, Mercedes Romano Rodriguez⁴, Nick Freemantle⁶

Affiliations

¹ Paediatric Pulmonology and Allergy, Children's Doctor Service, Heidelberg and University of Heidelberg, Germany.
² Respiratory Section, Department of Translational Medicine, University of Ferrara, Italy.
³ Department of Respiratory Medicine, Bispebjerg Hospital, University of Copenhagen, Denmark.
⁴ Global Market Access, ALK, Denmark.
⁵ Global Medical Affairs, ALK, Denmark.
⁶ Institute of Clinical Trials and Methodology UCL, UK.

Abstract

Background: Allergen immunotherapy (AIT) is the only causal treatment for respiratory allergy. Long-term real-life effectiveness of AIT remains to be demonstrated beyond the evidence from randomised controlled trials (RCTs).

Methods: REACT (Real world effectiveness in allergy immunotherapy) is a retrospective cohort study using claims data between 2007 and 2017. Study eligibility was a confirmed diagnosis of allergic rhinitis (AR), with or without asthma, and AIT. To ensure comparable groups, AIT-treated subjects were propensity score matched 1:1 with control subjects, using characteristic and potential confounding variables. Outcomes were analysed as within (pre vs post AIT) and between (AIT vs control) group differences across 9 years of follow-up (ClinicalTrial.gov: NCT04125888).

Findings: 46,024 AIT-treated subjects were matched with control subjects and 14,614 were included in the pre-existing asthma cohort. AIT-treated subjects were 29·5 (16·3) years and 53% were male. Compared to pre-index year, AIT was consistently associated with greater reductions compared to control subjects in AR and asthma prescriptions, including both asthma controller and reliever prescriptions. Additionally, the AIT group had significantly greater likelihood of stepping down asthma treatment (P <0·0001). In addition to the reduction in asthma treatment in the AIT group, a greater reduction in severe asthma exacerbations was demonstrated (P<0·05). Reductions in pneumonia with antibiotic prescriptions, hospitalisations, and duration of inpatients stays were all in favour of AIT.

Interpretation: The study extends the existing RCT evidence for AIT by demonstrating longer-term and sustained effectiveness of AIT in the real world. Additionally, in patients with concurrent asthma, AIT was associated with reduced likelihood of asthma exacerbations and pneumonia.

Funding: The study was funded by ALK A/S.

Keywords: AIT, allergy immunotherapy; AR, allergic rhinitis; Allergic rhinitis; Allergy; Allergy immunotherapy; Asthma; Effectiveness; FU, follow-up; HDM, house dust mite; HRU, health care resource utilisation; ICS, inhaled corticosteroids; INCS, intranasal corticosteroids; LABA, long-acting beta2-agonists; PSM, propensity score matching; RCT, randomised clinical trial; RWE, real world evidence; Real-world evidence; Retrospective cohort study; Rx, prescription; SABA, short-acting beta2-agonists; SCIT, subcutaneous immunotherapy; SLIT, sublingual immunotherapy.

Associated data

ClinicalTrials.gov/NCT04125888