A comparison of different methods of the allergen-specific immunotherapy in patients with pollinosis: the results of open randomized study
Authors: Nasunova A Y , Nenasheva N M 
Published: June 2020

Background. Allergen-specific immunotherapy (ASIT) is viewed as the only treatment that influences all patho-genetically significant parts of the allergic process in the initial and late phases of the IgE-mediated allergic reaction and modifies the abnormal immune reactivity to a specific allergen. Currently, sublingual (SLIT) and subcutaneous (SCIT) immunotherapy are most commonly used in clinical practice. Despite long experience of sublingual and subcutaneous immunotherapy application, questions remain about the preferred ASIT method and comparative effectiveness of different ASIT methods. This article evaluates the efficacy, benefits of SCIT and SLIT and highlights new findings related mechanisms and potential biomarkers. The aim of the study. To evaluate the comparative efficacy of different methods of ASIT (subcutaneous and sublingual) based on clinical data and biomarkers in the blood serum and other biological fluids in adult patients with allergic rhinoconjunctivitis (with/without asthma). Materials and methods. 60 patients with allergic rhinoconjunctivitis (with/without asthma) aged 18 to 50 were randomly assigned to 3 groups treated by sublingual immunotherapy with extracts of allergens, subcutaneous immunotherapy with extracts of allergens and subcutaneous with modified allergens (allergoids) respectively. Results. The efficiency of the first course of preseason ASIT (SCIT and SLIT) with extracts of allergens and aller-goids in the control of symptoms of allergic rhinoconjunctivitis (with/without asthma) was demonstrated. After the end of the first year pre-season ASIT data analysis scales (Total Symptom Score -TSS, Medircation Score -MS) revealed the best performance in the group of patients receiving SCIT with allergoids compared with patients receiving the SLIT with extracts of allergens: the scales of the TSS (p=0.023), MS (p=0.002). In addition, at the end of the maintenance phase of ASIT in patients treated with SCIT with allergoids the level of eosinophilic cationic protein (ECP) in the nasal lavage decreased by 22% (p=0.012), secretory immunoglobulin A (sIgA) in the nasal lavage increased by 70% (p=0.001), interleukin-10 (IL-10) in serum increased by 126% (p=0.006), allergen-specific IgG4 increased by 42% (p=0.01) from the initial values, that correlates with a decrease in the severity of clinical manifestations. In pollen season ECP level in nasal lavage was significantly (p=0.007) lower in a group of patients who received SCIT with allergoids compared with patients who received the SLIT with extracts of allergens. The most significant changes of serum level of IL-10 in the pollen season occurred in a group of patients receiving SCIT with allergoids compared with patients who received SLIT (p=0.013) and SCIT (p=0.001) with extracts of allergens. Conclusion. The study results deepen the existing understanding of the mechanisms of SCIT and SLIT. They allow to develop a comprehensive assessment of the therapy efficacy scheme based on clinical parameters and on monitoring of local (ECP, sIgA) and systemic biomarkers (IL-10, allergen-specific IgG4) as well.