Allergen-Specific Immunotherapy in the Treatment of Pediatric Asthma: A Systematic Review

CONTEXT: Treatment options for allergic asthma include allergen avoidance, pharmacotherapy, and allergen immunotherapy. OBJECTIVES: Summarize and update current evidence for the efficacy and safety of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) in pediatric allergic asthma. DATA SOURCES: PubMed, Embase, Cochrane Central Register of Controlled Trials (January 1, 2005, through May 8, 2017), ClinicalTrials.gov, and the US Food and Drug Administration Adverse Event Reporting System. We reevaluated trials from our 2013 systematic review. STUDY SELECTION: We included studies with children <= 18 years of age in which researchers reported on prespecified outcomes and had an intervention arm receiving aeroallergen SCIT or SLIT. Only randomized controlled trials (RCTs) were included for efficacy. RCTs and non-RCTs were included for safety outcomes. DATA EXTRACTION: Two reviewers extracted data. We included 40 studies (17 SCIT trials, 11 SLIT trials, 8 non-RCTs for SCIT safety, and 4 non-RCTs for SLIT safety). RESULTS: We found moderate-strength evidence that SCIT reduces long-term asthma medication use. We found low-strength evidence that SCIT improves asthma-related quality of life and forced expiratory volume in 1 second. There was also low-strength evidence that SLIT improves medication use and forced expiratory volume in 1 second. There was insufficient evidence on asthma symptoms and health care use. LIMITATIONS: There were no trials in which researchers evaluated asthma symptoms using a validated tool. Study characteristics and outcomes were reported heterogeneously. CONCLUSIONS: In children with allergic asthma, SCIT may reduce long-term asthma medication use. Local and systemic allergic reactions are common, but anaphylaxis is reported rarely.