Real-World Effectiveness and Safety of Allergen Immunotherapy with a Combination of Glutaraldehyde-Polymerized Allergen Extracts of Dermatophagoides spp. and Lepidoglyphus destructor in Adults and Children.

Mite-induced allergic respiratory diseases are a major global health concern, and evidence on allergen immunotherapy (AIT) combining allergens from different mite families remains limited, particularly for Lepidoglyphus destructor. This study evaluated the effectiveness and safety of subcutaneous allergen immunotherapy containing glutaraldehydempolymerized extracts of Dermatophagoides pteronyssinus, Dermatophagoides farinae, and L. destructor in mite-allergic patients in Spain. This retrospective multicenter study included 199 patients with allergic rhinoconjunctivitis, with or without asthma. Effectiveness outcomes included combined symptom and medication scores (CSMS), symptom scores, and medication use. Safety outcomes included adverse reactions. Mixed models for repeated measures showed significant improvements in rhinoconjunctivitis and asthma outcomes (all p < 0.001). Adjusted LS-mean rhinoconjunctivitis CSMS decreased by 50.7% at T1 and 76.1% at T4; symptom and medication scores decreased by 85.3% and 69.3%, respectively, at T4. Asthma CSMS decreased by 43.1% at T1 and 89.0% at T5, while symptom and medication scores decreased by 93.4% and 88.5%, respectively. Similar patterns were observed in children. No systemic reactions occurred. Twenty mild local reactions were recorded in 17 patients (8.5%), corresponding to an estimated rate of 0.32% across 6169 injections. This AIT was associated with sustained clinical improvement and a favorable safety profile in adults and children.