Effect of adjuvanted and standard sublingual immunotherapy on respiratory function in pure rhinitis due to house dust mite over a 5-year period

Can development of asthma and bronchial hyperreactivity be reduced by subcutaneous immunotherapy in adult patients with allergic rhinitis?

BACKGROUND

Allergic rhinitis can be associated with bronchial hyperreactivity (BHR) and create an increased risk for allergic asthma development. We aimed to investigate the effects of subcutaneous immunotherapy (SCIT) on BHR and asthma development in adult patients with allergic rhinitis.

METHODS

The retrospective case-control study was carried out between November 2018 and May 2019 in Süreyyapaşa Chest Diseases and Thoracic Surgery Training and Research Hospital. In this study, data was recorded for patients with a mite and/or grasses/cereals pollen allergy who were tested for BHR before planned SCIT, and who had allergic rhinitis, with or without asthma. The SCIT group was selected as those who received SCIT for at least one year. The control group was selected from those who were scheduled to receive SCIT but were waived and still receiving medication. Symptom scores, prick test results, PC20 levels (methacholine challenge that is a provocative concentration causing a 20% fall in FEV1), and the presence of asthma were recorded and compared with data from at least one year after treatment.

RESULTS

A total of sixty-eight subjects (22 males, 46 females; mean age 40.54 ± 12.27 years; SCIT: 40, Control: 28) were enrolled.Although the changes in log PC20 levels were not statistically significant in both SCIT and control groups after an average of 30-35 months of treatment, it was found to be significant in favor of the SCIT group when two groups were compared in terms of the change in log PC20 (p = 0.026). The development and improvement of asthma were not significantly different between the SCIT and control group but tended to increase in the control group. The percentage of patients with progressed/BHR was significantly higher in the controls (70.6% vs. 38.1%, p = 0.046).

DISCUSSION

In our real life study we have demonstrated the preventative effect of SCIT on BHR, but not on asthma developmen.

Delivery options for sublingual immunotherapy for allergic rhinoconjunctivitis: clinical considerations for North America

Background: Sublingual immunotherapy (SLIT) can be delivered via tablets (SLIT-T) or aqueous drops (SLIT-D). SLIT-D dosing recommendations using North American extracts were published in 2015. We review the 2015 recommendations in the context of recent research, and compare and contrast dosing, efficacy, safety, adherence, and cost of SLIT-T and SLIT-D for allergic rhinoconjunctivitis (ARC) in North America. Methods: Randomized controlled trials (RCT) of SLIT-D and SLIT-T trials were identified by a systematic PubMed search through March 1, 2022. Results: Dose-finding studies have been conducted for all approved SLIT-T; efficacy in North American populations was demonstrated in 11 RCTs. Approved SLIT-T are uniform internationally. Few dose-finding studies for SLIT-D have been conducted using North American extracts; efficacy was demonstrated in 2 RCTs. Extrapolation of dosing from SLIT-D studies conducted with extracts from other geographic regions is unreliable. Since the 2015 SLIT-D dosing recommendations, no new RCTs of SLIT-D have been conducted with North American extracts, whereas 6 SLIT-T RCTs have since been conducted in North America. Local allergic reactions are the most common adverse events with SLIT-T and SLIT-D, but both can induce systemic allergic reactions. Adherence to SLIT-D and SLIT-T remains a challenge. Patients must pay for SLIT-D directly, whereas SLIT-T is usually covered by insurance. Conclusion: As part of shared decision-making, patients should be informed about the scientific evidence supporting the use of SLIT-T and SLIT-D for ARC.

Efficacy of a house dust mite sublingual immunotherapy tablet as add-on dupilumab in asthma with rhinitis

BACKGROUND

HDM SLIT is one of the disease-modifying treatment for allergic asthma, and has demonstrated efficacy in clinical trials. Dupilumab, blocks IL-4 and IL-13 signaling, key drivers of type 2 inflammation, and is approved for patients with uncontrolled, moderate-to-severe asthma. The aim of this study was to evaluate outcomes after HDM SLIT initiation in asthma with rhinitis not optimally controlled with dupilumab in a real-world setting.

METHODS

At baseline and 48 weeks after treatment, asthma control questionnaire (ACQ)-5, asthma quality of life questionnaire (AQLQ) and rhinoconjunctivitis quality of life questionnaire (RQLQ) were assessed. Spirometry, type 2 inflammatory biomarkers and quantitative computed tomographic parameters of airway remodeling were also collected.

RESULTS

Of 47 patients received HDM SLIT and 41 completed the study. Combined HDM SLIT and dupilumab improved ACQ-5 (p < 0.05), AQLQ (p < 0.05), RQLQ (p < 0.05), and increased lung function and reduced FeNO (p < 0.05) and airway percentage wall area, and wall thickness (each, p < 0.05). The change in ACQ-5 and AQLQ score correlated with both changes in FeNO and FEV₁ percent predicted. Multiple regression analysis showed that the change in FEV₁ percent predicted was independent factor for improvement of AQLQ (r² = 0.510, p = 0.012). Based on ROC analysis for predicting SLIT responders, the baseline area under the curves in serum HDM specific-IgE, total IgE and FEV₁ percent predicted were high (>0.8).

CONCLUSIONS

These results support the benefits of adding HDM SLIT to pharmacotherapy plus dupilumab in uncontrolled asthma with rhinitis.

Recent Advances in Allergen-Specific Immunotherapy as Treatment for Allergic Asthma: A Practical Overview

The Global Initiative for Asthma Report updated in 2019 stated that potential benefits of allergen immunotherapy (AIT), compared to pharmacological and avoidance options, must be weighed against the risk of adverse effects and the inconvenience and cost of the prolonged course of therapy in asthma. Thus, with the aim of clarifying some aspects with regard to the possible use of AIT in allergic asthma treatment armamentarium, a group of expert allergists from the Spanish Allergy and Clinical Immunology Scientific Society (SEAIC), particularly from the Immunotherapy and Asthma Interest Groups developed a frequently asked questions in clinical practice. This document updates relevant topics on the use of AIT in asthma and could facilitate physician clinical decisions and improve health outcomes for individual patients.

Long and winding road: from infant wheeze to adult asthma

PURPOSE OF REVIEW

This review aims to recognize the multifactorial cause of asthma, from the influence of mother until adulthood, highlight the main characteristics of the disease at different ages and summarize the evidence of potential prevention strategies.

RECENT FINDINGS

To date, regarding the prenatal period, the presence of specific genes, maternal asthma, drugs, and tobacco exposure are the most relevant predisposing features for an asthmatic offspring. For newborns, preterm, bronchopulmonary dysplasia, and low birth weight has been associated with low lung function. Among young children, atopic dermatitis, lower respiratory tract infections, and increased levels of total Immunoglobulin E (IgE) and allergen-specific IgE are important determinants.Breastfeeding has been demonstrated being protective for the onset of asthma. Allergen immunotherapy has also been shown to have significant preventive effect decreasing asthma development. Inhaled corticosteroids use in early childhood prevents exacerbations but does not alter the natural history of asthma. Other interventions, such as the use of palivizumab, probiotics, vitamin D supplementation, and fish consumption presented controversial results.

SUMMARY

A good knowledge of risk factors for asthma development, from prenatal period to adulthood, may lead to efficacious preventive strategies. Further data of long-term follow-up in population-based studies according to different phenotypes are needed.

Prevention of Asthma: Targets for Intervention

Approximately 300 million people worldwide are estimated to be affected by asthma, and the number of patients affected is growing exponentially-with potential for an additional 100 million people affected by the condition by 2025. With this increasing burden of disease, there is high motivation to discover effective prevention strategies. Strategies aimed at stalling the atopic progression, modifying the microbiome, preventing respiratory viral infections, and reducing the impact of toxin/pollutant exposure through dietary supplements have had limited success in the prevention of asthma. This is likely because asthma is heterogenous and is influenced by different genetic and environmental factors. Genes underlie a predisposition to asthma and allergic sensitization, whereas exposure to allergens, respiratory infections, and pollution may modify asthma pathogenesis and the variation in severity seen among individuals. Future advances in asthma prevention may include a more personalized approach: genetic variations among susceptible individuals with distinct asthma phenotypes or different biomarkers of disease may help individualize prevention strategies and render them more . In this article, we summarize interventions that have been studied for the prevention of asthma and identify some of the clinical trials that are actively underway in asthma prevention.

Preventing the development of asthma: stopping the allergic march

PURPOSE OF REVIEW

To describe important precipitants of asthma and allergic disease, to highlight the links between these triggers and modifications within the immune system, and to examine innovative research regarding asthma prevention with focus on attenuating the atopic march.

RECENT FINDINGS

Allergen avoidance, allergen immunotherapy, IgE antagonists, prevention and treatment of respiratory infections, as well as management of gastrointestinal and respiratory dysbiosis have been considered as strategies in asthma prevention. Antenatal vitamin D supplementation in expectant mothers and aggressive control of atopic dermatitis to prevent the development of other allergic conditions were carefully studied as well.

SUMMARY

Asthma is a major cause of morbidity and lost productivity. Despite the tremendous burden of this disease, the scientific community is still struggling to find an effective means of prevention. The contribution of genetics to the development of atopy cannot be altered, but environmental changes as well as pharmacotherapy have been studied as modifiable risk factors. Many trials to date have been effective only for subjects with certain characteristics. This is likely because asthma is a heterogenous condition, with a variety of triggers and clinical phenotypes. Thus far, a universally effective prevention strategy has eluded us. However, if an intervention can be found to prevent asthma and the allergic march, it will greatly improve quality of life for millions of sufferers and decrease healthcare expenditures.

Effect of Sublingual Immunotherapy on Airway Inflammation and Airway Wall Thickness in Allergic Asthma

BACKGROUND

The efficacy of the standardized quality (SQ) house dust mite (HDM) sublingual immunotherapy (SLIT) has been demonstrated for respiratory allergic disease. However, the effects of SLIT on inflammation and structural changes of the airways are still unknown.

OBJECTIVE

The aim of this study was to assess the effects of the 6 SQ-HDM SLIT on airway inflammation and airway geometry in allergic asthma and rhinitis.

METHODS

One hundred two asthmatic patients with rhinitis sensitized to HDM were randomized to receive either SLIT plus pharmacotherapy or standard pharmacotherapy alone, for 48 weeks. Fractional exhaled nitric oxide (FeNO), pulmonary function, quantitative computed tomography, and clinical symptoms were performed at baseline and end of the study.

RESULTS

Compared with pharmacotherapy, SLIT demonstrated a significant reduction of FeNO (P < .01), airway wall area/body surface area (WA/BSA, P < .001), wall thickness (T/√BSA, P < .001), percentage wall area (WA/Ao, P < .01), increase in luminal area (Ai/BSA, P < .05), improvement of airflow limitation (P < .001), and clinical symptom scores (P < .05). The change in forced expiratory volume in 1 second (FEV₁) was correlated with both changes in FeNO and airway dimensions. Multiple regression analysis showed that the change in FeNO was independently associated with an increase in FEV₁ in the SLIT group (r² = 0.623, P = .037).

CONCLUSIONS

Adding 6 SQ-HDM SLIT to standard asthma therapy provides a significant improvement in symptoms and pulmonary function compared with pharmacotherapy. Improvement of airflow limitation with SLIT was associated with the decrease in eosinophilic airway inflammation.

Preventive actions of allergen immunotherapy: the facts and the effects in search of evidence

Allergen immunotherapy (AIT) is the only treatment that works on the causes of allergy. Available AIT nowadays are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) for allergic rhinitis and asthma, while for allergy to Hymenoptera venom only subcutaneous route is recommended. A bulk of trials and meta-analyses demonstrated that efficacy and safety of AIT in decreasing allergic clinical symptoms and use of rescue medications, while its preventive capacity is yet under investigation. The most important of these effects is the prevention of potentially fatal anaphylactic reactions to Hymenoptera stings by venom immunotherapy (VIT). A certain number of studies thus far available showed that AIT, in both forms, is able to prevent the progress of allergic rhinitis into asthma and the development of new sensitizations. These effects should be related to the mechanisms of action of AIT. In fact, it has been demonstrated that both SCIT and SLIT are able to modify the allergen presentation by dendritic cells, with result in modification of the phenotype of allergen-specific T cells, switching from the typical of allergic inflammation Th2-type response to a Th1-type one. Also allergen-specific T regulatory (Treg) cells play a pivotal role by producing suppressive cytokines, such as IL-10 and TGF-beta. However, the only plain evidence of a preventive effect concerns VIT, while the other outcomes need to be furtherly investigated.