Background: Most previous studies used aluminum hydroxide-absorbed allergen extracts in evaluating the potential therapeutic roles of intralymphatic allergen-specific immunotherapy (ILAIT). In this study, we evaluated the therapeutic efficacy and safety of ILAIT with L-tyrosine-adsorbed allergen extracts of Dermatophagoides farinae, D. pteronyssinus, cat, dog, or mixtures thereof, in patients with allergic rhinitis induced by these allergens.
Methods: In this randomized, double-blind, placebo-controlled trial, study subjects received three intralymphatic injections of L-tyrosine-adsorbed allergen extracts (active group) or saline (placebo group) at 4-week intervals.
Results: Although ILAIT reduced daily medication use and skin reactivity to HDM and cat allergens at 4 months after treatment, overall symptom score on a visual analog scale (VAS), sinonasal outcome test-20 (SNOT-20), rhinoconjunctivitis quality of life questionnaire (RQLQ), daily symptom score (dSS), daily medication score (dMS), daily symptom medication score (dSMS), nasal reactivity to HDM allergen, and basophil activity to HDM, cat, and dog allergens at 4 months and 1 year after treatment were similar between the treatment and control groups. Intralymphatic injection was more painful than a venous puncture, and pain at the injection site was the most frequent local adverse event (12.8%); dyspnea and wheezing were the most common systemic adverse events (5.3%).
Conclusions: ILAIT with L-tyrosine-adsorbed allergen extracts does not exhibit profound therapeutic efficacy in allergic rhinitis and can provoke moderate-to-severe systemic reactions and cause pain at the injection site.
Trial registration: clinicaltrials.gov: NCT02665754; date of registration: 28 January 2016.
Keywords: Adverse events; Allergen immunotherapy; Allergic rhinitis; Intralymphatic injection; Treatment efficacy.