House dust mite subcutaneous immunotherapy in Chinese patients with allergic asthma and rhinitis

A novel dose-adjustment protocol for interrupted subcutaneous immunotherapy in children with allergic rhinitis

Aim: To assess the effectiveness and safety of a new protocol for adjusting doses during interrupted subcutaneous immunotherapy maintenance, exceeding an 8-week interval, with mite allergen injections in children with allergic rhinitis. Patients & methods: 194 children with allergic rhinitis who underwent subcutaneous immunotherapy and experienced interruptions lasting more than 8 weeks during maintenance were enrolled. Following the adoption of a novel dose-adjustment protocol, a real-world study was conducted. Results: After 3 years of subcutaneous immunotherapy, the novel group exhibited a significant reduction in allergy symptoms compared with baseline. Systemic reactions related to the novel protocol did not significantly increase. Conclusion: The novel protocol was deemed safe and effective, offering advantages of time savings and reduced burdens.

Clinical and experimental treatment of allergic asthma with an emphasis on allergen immunotherapy and its mechanisms

Allergen immunotherapy (AIT) is currently the only form of treatment that modifies allergic asthma. Pharmacotherapy alone seeks to control the symptoms of allergic asthma, allergic rhinitis, and other atopic conditions. In contrast, AIT can induce long-term physiological modifications through the immune system. AIT enables individuals to live improved lives many years after treatment ends, where they are desensitized to the allergen(s) used or no longer have significant allergic reactions upon allergen provocation. The leading forms of treatment with AIT involve injections of allergen extracts with increasing doses via the subcutaneous route or drops/tablets via the sublingual route for several years. Since the initial attempts at this treatment as early as 1911 by Leonard Noon, the mechanisms by which AIT operates remain unclear. This literature-based review provides the primary care practitioner with a current understanding of the mechanisms of AIT, including its treatment safety, protocols, and long-term efficacy. The primary mechanisms underlying AIT include changes in immunoglobulin classes (IgA, IgE, and IgG), immunosuppressive regulatory T-cell induction, helper T cell type 2 to helper T cell type 1 cell/cytokine profile shifts, decreased early-phase reaction activity and mediators, and increased production of IL-10, IL-35, TGF-β, and IFN-γ. Using the databases PubMed and Embase, a selective literature search was conducted searching for English, full-text, reviews published between 2015 and 2022 using the keywords (with wildcards) "allerg*," "immunotherap*," "mechanis*," and "asthma." Among the cited references, additional references were identified using a manual search.

Chinese Guideline on Allergen Immunotherapy for Allergic Rhinitis: The 2022 Update

In the last few decades, there has been a progressive increase in the prevalence of allergic rhinitis (AR) in China, where it now affects approximately 250 million people. AR prevention and treatment include allergen avoidance, pharmacotherapy, allergen immunotherapy (AIT), and patient education, among which AIT is the only curative intervention. AIT targets the disease etiology and may potentially modify the immune system as well as induce allergen-specific immune tolerance in patients with AR. In 2017, a team of experts from the Chinese Society of Allergy (CSA) and the Chinese Allergic Rhinitis Collaborative Research Group (C2AR2G) produced the first English version of Chinese AIT guidelines for AR. Since then, there has been considerable progress in basic research of and clinical practice for AIT, especially regarding the role of follicular regulatory T (TFR) cells in the pathogenesis of AR and the use of allergen-specific immunoglobulin E (sIgE) in nasal secretions for the diagnosis of AR. Additionally, potential biomarkers, including TFR cells, sIgG4, and sIgE, have been used to monitor the incidence and progression of AR. Moreover, there has been a novel understanding of AIT during the coronavirus disease 2019 pandemic. Hence, there was an urgent need to update the AIT guideline for AR by a team of experts from CSA and C2AR2G. This document aims to serve as professional reference material on AIT for AR treatment in China, thus improving the development of AIT across the world.

Febuxostat Alleviates Allergic Rhinitis by Inhibiting Inflammation and Monocyte Adhesion in Human Nasal Epithelial Cells via Regulating KLF6

Introduction

Febuxostat is a novel inhibitor of xanthine oxidase that suppresses cell adhesion molecules-mediated (CAMs) inflammation by activating KLF6. In this study, we explored the therapeutic function and potential mechanisms of febuxostat against allergic rhinitis (AR).

Methods

We investigated the role of febuxostat through in vitro cell and in vivo animal experiments. Human nasal epithelial cells (hNECs) were cultured with histamine as an in vitro model. To establish the AR animal model, rats were exposed to ovalbumin. Rats were randomly grouped into control, model, 7.5 mg/kg febuxostat, and 15 mg/kg febuxostat groups.

Results

In the in vitro study, we found significantly increased release of lactate dehydrogenase, elevated production of inflammatory factors and chemokines, and upregulated CAMs in histamine-treated hNECs. However, these results were significantly reversed for the 10 and 20 μM febuxostat treatments. The enhanced adhesion between hNECs and monocytes induced by histamine was dramatically repressed by febuxostat. In the vivo experiments, we observed that febuxostat ameliorated the increased sneezing times, the number of nose scratching episodes, and elevated HE pathological scores as well as alleviated the inflammation in nasal mucous tissues of AR mice. We found that KLF6, which was downregulated in histamine-treated hNECs, was significantly upregulated by febuxostat. The inhibitory effects of febuxostat on the expression levels of CAMs and adhesion between histamine-treated hNECs and monocytes were significantly abolished by the knockdown of KLF6.

Conclusion

Febuxostat alleviates AR by inhibiting inflammation and monocyte adhesion in human nasal epithelial cells through the regulation of KLF6.

Efficacy of subcutaneous house dust mite immunotherapy in patients with moderate to severe allergic rhinitis

Aim: To evaluate the efficacy of subcutaneous immunotherapy (SCIT) for the treatment of allergy to house dust mites (HDM) in adults with moderate/severe allergic rhinitis (AR). Methods: Patients sensitized to HDM were randomized to SCIT plus rescue medication (Group A, n = 38) or rescue medication alone (Group B, n = 18), and assessed at baseline and 2, 6 and 12 months. Results: At month 12, Group A presented significant improvement with respect to baseline as evaluated by a visual analogue scale at three concentrations of antigen (0.1, 1 and 10 IR/ml; p < 0.0001). Group A presented significant decreases in symptom scores after 2 months of treatment, which were maintained after 1 year. After 12 months of treatment, Group A showed rescue medication consumption reductions (p < 0.001) and quality of life improvements (p < 0.0001). SCIT elicited a strong immunological response and was well tolerated. Conclusion: SCIT is efficacious for HDM allergy in patients with AR, generating a strong immunological response. Trial Registration Number: EUCTR2009-018155-16-ES (Cochrane Central Register of Controlled Trials).

Safety of semi-depot house dust mite allergen extract in children and adolescents with allergic rhinitis and asthma

Aim: Multicenter study to investigate the safety of mite extract product Novo-Helisen Depot, Strengths 1 to 3 (NHD3), as subcutaneous immunotherapy (SCIT), in Chinese children and adolescents with allergic rhinitis (AR) and allergic asthma (AA). Patients & methods: We evaluated SCIT-related adverse events (AEs) during NHD3 14-week initial therapy in children (5-11 years) and adolescents (12-17 years) with perennial symptomatic AR and AA. Results: Among 3600 injections in 250 patients, 361/3600 (10.0%) injections caused SCIT-related AEs in 96/250 (38.4%) patients, 321/3600 injections (8.9%) caused local reactions in 89/250 (35.6%) and 40/3600 injections (1.1%) caused systemic reactions in 23/250 (9.2%). Conclusion: Initial SCIT treatment using NHD3 was safe and well tolerated in Chinese children and adolescents with AR and AA.

Safety and effectiveness of a microcrystalline tyrosine-associated mite extract immunotherapy for allergic rhinitis

Aim: To assess the safety and effectiveness of an allergen immunotherapy (AIT) with a microcrystalline tyrosine-associated mite allergoid in real-world patients with allergic rhinitis (AR). Materials & methods: Retrospective, multicenter study assessing the safety of AIT in patients aged 5 to 65 years with AR, with or without asthma, sensitized to mites. Secondary objective was effectiveness, measured as unscheduled visits to healthcare centers and emergency rooms, rhinitis and asthma evolution, medication use and patients' and physicians' disease perception 12 months before and after treatment. Results: The 306 patients evaluated, with a mean (standard deviation) age of 29.68 (14.66) years, received different treatment compositions and regimens, and 25 (8.2%) experienced nonserious adverse reactions. Unscheduled visits to the specialist and emergency room admissions significantly decreased after immunotherapy (mean [standard deviation] 2.11 [1.95] and 0.3 [0.93] vs 0.66 [1.09] and 0.02 [0.2], before and after treatment, respectively). Rhinitis and asthma classification ('AR and its impact on asthma' and 'Guía Española para el Manejo del Asma', respectively) significantly changed (p < 0.0001 for all classifications), showing symptom reduction after AIT. Median (interquartile range)-combined rhinitis and combined asthma medication scores significantly decreased (4.0 [1.33, 7.0] vs 0.25 [0, 10.0]; p < 0.0001 and 6.94 [1.5, 6.0] vs 0.67 [0, 4.67]; p < 0.0001) within 12 months before and after starting AIT, respectively. Conclusion: AIT with microcrystalline tyrosine-associated mite allergoid appears to be safe and effective in treating rhinitis caused by mites.

Effects of Perennial Allergen Immunotherapy in Allergic Rhinitis in Patients with/without Asthma: A-Randomized Controlled Real-Life Study

BACKGROUND

There have been very few studiesin real-life settingscomparing the treatment effects of allergen immunotherapy (AIT) and pharmacotherapy for perennial allergic rhinitis (AR).

OBJECTIVE

This study was performed to compare AIT and pharmacotherapy in terms of their effects on the symptom control and quality of life (QOL) of AR patients with/without asthma.

METHODS

A total of 250 patients diagnosed with AR with/without asthma were included and assigned to the immunotherapy (AIT plus pharmacological treatment) or control (pharmacological treatment only) group. Clinical and medication scores, QOL scores, and lung function (forced expiratory volume in one second as a percentage; FEV1%) were measured at baseline and 3 years after the start of treatment.

RESULTS

This study showed that there was clinical improvement in AR symptoms in the AIT group, whereas standard pharmacotherapy alone had no significant effect on nasal symptoms. The QOL and satisfaction scores, as evaluated with a visual analogue scale (VAS), were further improved compared to the pharmacotherapy group. There was a significant improvement in medication scores in both AIT groups. According to our results, while total asthma scores and asthma control test scores were significantly improved in the HDM AIT group, they did not change in the Parietaria pollen AIT group. In our study FEV1% was increased compared to the baseline value in the AIT group, but it was not statistically significant. On the other hand, FEV1% remained without any improvement in patients on standard pharmacotherapy.

CONCLUSION

Perennial AIT was found to be superior to pharmacotherapy in decreasing symptoms as well as in improving QOL scores in AR patients with/without asthma. HDM AIT was more effective for asthma symptoms than Parietaria pollen AIT.