Specific Allergy Immunotherapy for Allergic Rhinitis: Subcutaneous and Sublingual

Identification of key genes and the pathophysiology associated with allergen-specific immunotherapy for allergic rhinitis

BACKGROUND

Allergen-specific immunotherapy (AIT) is a causative treatment in allergic rhinitis (AR), comprising long-term allergen administration and over three years of treatment. This study is carried out for revealing the mechanisms and key genes of AIT in AR.

METHODS

The present study utilized online Gene Expression Omnibus (GEO) microarray expression profiling dataset GSE37157 and GSE29521 to analyze the hub genes changes related to AIT in AR. Based on limma package, differential expression analysis for the two groups (samples of allergic patients prior to AIT and samples of allergic patients undergoing AIT) was performed to obtain differentially expressed genes (DEGs). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs were conducted using DAVID database. A Protein-Protein Interaction network (PPI) was built and a significant network module was acquired by using Cytoscape software (Cytoscape, 3.7.2). Utilizing the miRWalk database, we identified potential gene biomarkers, constructed interaction networks of target genes and microRNAs (miRNAs) using Cytoscape software, and explore the cell type-specific expression patterns of these genes in peripheral blood using publicly available single-cell RNA sequencing data (GSE200107). Finally, we are using PCR to detect changes in the hub genes that are screened using the above method in peripheral blood before and after AIT treatment.

RESULTS

GSE37157 and GSE29521 included 28 and 13 samples, respectively. A total of 119 significantly co-upregulated DEGs and 33 co-downregulated DEGs were obtained from two datasets. The GO and KEGG analyses demonstrated that protein transport, positive regulation of apoptotic process, Natural killer cell mediated cytotoxicity, T cell receptor signaling pathway, TNF signaling pathway, B cell receptor signaling pathway and Apoptosis may be potential candidate therapeutic targets for AIT of AR. From the PPI network, 20 hub genes were obtained. Among them, the PPI sub-networks of CASP3, FOXO3, PIK3R1, PIK3R3, ATF4, and POLD3 screened out from our study have been identified as reliable predictors of AIT in AR, especially the PIK3R1.

CONCLUSION

Our analysis has identified novel gene signatures, thereby contributing to a more comprehensive understanding of the molecular mechanisms underlying AIT in the treatment of AR.

Alternatives to Subcutaneous Immunotherapy for Allergic Rhinitis

Allergic rhinitis (AR) is an important public health issue worldwide due to its increasing prevalence and impact on quality of life, school performance, and work productivity. Subcutaneous immunotherapy (SCIT) is used to treat AR and involves repeated injections of allergen extracts. SCIT is used for cases of severe AR with symptoms that are not adequately controlled by medication, when the side effects of medication limit treatment options, or where the aim is to cure rather than symptomatically treat. Although SCIT is effective, it is not necessarily curative. Furthermore, there is also a low but present risk of systemic allergic reactions, with systemic side effects occurring in less than 0–1% of treated patients. Sublingual immunotherapy (SLIT) has emerged as an effective and safe alternative to SCIT. SCIT and SLIT are the only immunotherapies currently available for AR. In addition to sublingual administration as an alternative to SCIT, other routes of antigen administration have been attempted with the goal of increasing safety while maintaining efficacy. This review discusses the efficacies of SCIT and SLIT, their mechanisms, the utility of intralymphatic immunotherapy (ILIT) as an alternative route of antigen administration, and the potential for immunotherapy using other routes of antigen administration.

Allergic sensitization in patients with rhinitis and bronchial asthma in Ningxia region of China

BACKGROUND

Allergic rhinitis and bronchial asthma are common allergic diseases. The pattern of dominant allergens depends on the degree of urbanization and the geographic region. The present study characterized the allergens of patients with allergic rhinitis and bronchial asthma in Ningxia region of China.

METHODS

A total of 309 patients were enrolled in this study. Western blotting assays were performed of the serum samples to evaluate allergen-specific IgE antibody for inhaled and ingested allergens. Statistical analysis was performed to compare the positive rate among different subgroups.

RESULTS

Among the 309 patients, 221 of them had positive test results. There were 157 positive cases for ingested allergens and 174 positive cases for inhaled allergens. No significant differences in positive rates were found between the ingested and inhaled allergens. Among the inhaled allergens, Artemisia was the most frequent allergen, followed by fungi and dog hair. Cashew was the most common ingested allergen, followed by crab, mango, and beef. Further analysis showed no significant differences in positive rate between males and females. However, significant differences in positive rate of inhaled and ingested allergens were found between children (1-13 years old) and adults (above 18 years old) (P < .05), while no significant differences were found between the children and teenagers (14-18 years old). For the comparison between teenagers and adults, significant difference in positive rate was found only in the ingested allergen.

CONCLUSION

This study provided the characteristics of allergens in Ningxia population, providing clinical and epidemiological data for prevention and treatment of the diseases in the region.

Subcutaneous immunotherapy with depigmented-polymerized allergen extracts: a systematic review and meta-analysis

BACKGROUND

Double-blind, placebo-controlled trials (DBPCTs) have confirmed the efficacy of allergen-specific immunotherapy (AIT) with depigmented-polymerized allergen extracts (DPAEs). This systematic review evaluates the efficacy of AIT using different allergens in different severity stages of rhinoconjunctivitis with or without asthma in the pollen studies and asthma and rhinitis in the house dust mite studies in comparison to placebo.

METHODS

We used MEDLINE, Embase, CENTRAL and LILACS databases to review DBPCTs published until July 2016. The combined symptom and medication score (cSMS) served as primary endpoint. The total rhinoconjunctivitis symptom score (RCSS) and total score in Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) were secondary efficacy endpoints. Solicited local and systemic adverse events were secondary safety endpoints. We assumed a random effects model with standardized mean differences (SMDs) or mean differences as summary statistics. In a subgroup analysis, we classified the studies following the GINA (Global Initiative for Asthma) and ARIA (Allergic Rhinitis and its Impact on Asthma) guidelines for rhinoconjunctivitis and asthma severity.

RESULTS

Six DBPCTs in pollen and 2 trials in house dust mites (HDM) were selected. Patients (N = 915) with intermittent or mild persistent asthma were included in 3 (37.5%) and 5 (62.5%) trials, respectively. Two (25%) HDM studies included patients with moderate persistent asthma, 4 trials patients with moderate-to-severe rhinoconjunctivitis. Treatment periods ranged from 12 to 24 months. AIT with DPAEs yielded significantly lower cSMS (SMD: 1.9, 95% CI: 0.9-2.8) and RQLQ (SMD: 0.3, 95% CI: 0.1-0.5) values than did placebo. An exploratory analysis of cSMS and RCSS suggested that the efficacy of AIT treatment with DPAEs was higher in trials including patients with more severe rhinoconjunctivitis and asthma. A publication bias was not detected. Heterogeneity between individual studies was explained by differences in severity. Patients receiving DPAEs did not experience a significantly higher risk of local (OR: 1.55, 95% CI: 0.86-2.79) or systemic reactions (OR: 1.94, 95% CI: 0.98-3.84).

CONCLUSIONS

Compared to placebo, AIT with DPAEs is effective in patients with pollen- or HDM-induced rhinoconjunctivitis with or without allergic asthma and improves health-related quality of life. It does not differ significantly in safety and tolerability.

[Costs of allergic diseases and saving potential by allergen-specific immunotherapy : A personal assessment]

BACKGROUND

The burden of allergic diseases is of particular relevance for the economy and the social welfare and health insurance framework. Allergic rhinitis (AR) has a life-time prevalence of approximately 30% and is one of the most common chronic diseases with considerable socioeconomic impact thus leading to substantial direct, indirect and intangible costs. This article explores the common hypothesis that allergen-specific immunotherapy (ASIT) saves national economic expenses in the long term in comparison to other standard symptomatic treatment or no therapy.

METHODS

We conducted a selective search and analysis of the literature in PubMed and Medline including otherwise listed publications in German. Using a predefined model and data extrapolation over 9 years for data from different sources and short-term clinical studies we further discuss the problems and difficulties in analyzing heterogeneous datasets.

RESULTS

Using a health-economic model with currently available and accepted variables ASIT proves to be cost-effective in comparison to symptomatic treatment in allergic rhinitis; however, numerous parameters from other models have to be controlled, such as adherence to therapy and therapy discontinuation, heterogeneous costs for different treatment modalities, effect sizes with respect to symptoms including cross-influences with symptomatic rescue medication, duration of efficacy after treatment discontinuation and asthma protection.

DISCUSSION

The personal appraisal of the authors demonstrates not only the current knowledge but also the problems in health economical evaluation of ASIT in allergic diseases.

The changes in different symptom scores during subcutaneous immunotherapy in Chinese house dust mite allergic patients: a two-year, observational study

BACKGROUND

Subcutaneous immunotherapy is an effective and safe treatment for allergic rhinitis and allergic asthma. Different symptom scores are used to evaluate the efficacy of subcutaneous immunotherapy in clinical trials.

METHOD

A total of 58 allergic rhinitis patients sensitised to house dust mites, with or without mild asthma, were included. Symptom score, medication score, visual analogue scale score and quality of life were assessed before and after 6, 12 and 24 months of subcutaneous immunotherapy.

RESULTS

After two years of subcutaneous immunotherapy, asthma symptom scores nearly reached zero, whereas the scores remained higher for nasal symptoms. The changes in asthma symptom scores were markedly different (p &lt; 0.05) and occurred faster than the changes in nasal symptom scores when compared between monosensitised and polysensitised groups. Significant reductions in visual analogue scale score and medication score were demonstrated after subcutaneous immunotherapy.

CONCLUSION

Two-year subcutaneous immunotherapy with house dust mite vaccine is an effective treatment for both monosensitised and polysensitised allergic patients. The changes in asthma symptom scores were markedly different and occurred quicker than the changes in nasal symptom scores in Chinese house dust mite allergic patients.

Dose-finding study of carbamylated monomeric allergoid tablets in grass-allergic rhinoconjunctivitis patients

AIM

To determine the optimal effective and safe dose of sublingual immunotherapy tablets containing carbamylated monomeric allergoids in patients with grass pollen-induced allergic rhinoconjunctivitis.

METHODS

In this prospective, randomized, double-blind, active-controlled, multicenter, Phase II study, four different daily doses were applied preseasonally for 12 weeks.

RESULTS

Of 158 randomized adults, 155 subjects (safety population) received 300 units of allergy (UA)/day (n = 36), 600 UA/day (n = 43), 1000 UA/day (n = 39), or 2000 UA/day (n = 37). After treatment, 54.3, 47.6, 59.0 and 51.4% of patients, respectively, ceased to react to the highest allergen concentration in a conjunctival provocation test. Furthermore, the response threshold improved in 70.4, 62.9, 76.7 and 66.7% of patients, respectively. No serious adverse events occurred.

CONCLUSION

This study found 1000 UA/day to be the optimal effective and safe dose.

Cost-effectiveness of grass pollen subcutaneous immunotherapy (SCIT) compared to sublingual immunotherapy (SLIT) and symptomatic treatment in Austria, Spain, and Switzerland

BACKGROUND

While specific immunotherapy (SIT) has been proven to be cost-effective for the treatment of allergic rhinitis compared to symptomatic treatment, there is a lack of European studies in which sublingual (SLIT) and subcutaneous (SCIT) immunotherapy were compared. The present analysis is focused on the cost-effectiveness of SCIT compared to SLIT and symptomatic treatment of grass pollen allergy in Austria, Spain, and Switzerland. It will address specific properties of the underlying healthcare systems.

METHODS

The investigation is based on a previously published health economic model calculation. This was designed as a Markov model with pre-defined health stages and a duration of 9 years covering specific preparations for SCIT (Allergovit) and SLIT (Oralair). The effectiveness was assessed as symptom-score based quality-adjusted life years (QALYs). Additionally, total cost has been determined as well as the cost-effectiveness of SCIT. The robustness of model results was proved in further sensitivity analyses.

RESULTS

With regard to the effectiveness of both SCIT and SLIT, preparations were dominant compared to pharmacological symptomatic therapy. Both strategies were associated with additional cost, but, combined with the results on effectiveness, both have to be regarded as cost-effective. A direct comparison of the SCIT (Allergovit) and SLIT (Oralair) showed lower total costs of SCIT vs SLIT for Austria, Spain, and Switzerland (€1,368 vs €2,012, €2,229 vs €2,547, and €1,901 vs €2,220) and superior effectiveness (SCIT =8.02 QALYs; SLIT =7.98 QALYs; and symptomatic therapy =7.90 QALYs).

CONCLUSION

In patients with allergic rhinitis, SIT offers cost-effective treatment options compared to symptomatic treatment. When comparing SCIT (Allergovit) and SLIT (Oralair), SCIT was dominant in terms of QALYs as well as costs, in particular due to a slightly higher patient compliance and lower drug costs.

IV Brazilian Consensus on Rhinitis - an update on allergic rhinitis

INTRODUCTION

The guidelines on allergic rhinitis aim to update knowledge about the disease and care for affected patients. The initiative called "Allergic Rhinitis and its Impact on Asthma", initially published in 2001 and updated in 2008 and 2010, has been very successful in disseminating information and evidence, as well as providing a classification of severity and proposing a systemized treatment protocol. In order to include the participation of other medical professionals in the treatment of allergic rhinitis, it is important to develop algorithms that accurately indicate what should and can be done regionally.

OBJECTIVE

To update the III Brazilian Consensus on Rhinitis - 2012, with the creation of an algorithm for allergic rhinitis management.

METHODS

We invited 24 experts nominated by the Brazilian Association of Allergy and Immunology, Brazilian Association of Otorhinolaryngology and Head and Neck Surgery and Brazilian Society of Pediatrics to update the 2012 document.

RESULTS

The update of the last Brazilian Consensus on Rhinitis incorporated and adapted the relevant information published in all "Allergic Rhinitis and its Impact on Asthma" Initiative documents to the Brazilian scenario, bringing new concepts such as local allergic rhinitis, new drugs and treatment evaluation methods.

CONCLUSION

A flowchart for allergic rhinitis treatment has been proposed.

The Role of the Level of Interleukin-33 in the Therapeutic Outcomes of Immunotherapy in Patients with Allergic Rhinitis

Introduction  Allergic rhinitis (AR) affects up to 40% of the population and results in nasal itching, congestion, sneezing, and clear rhinorrhea.

Objectives  This study aimed to evaluate the changes in the clinical symptoms and in the level of serum interleukin (IL)-33 before and after pollen immunotherapy (IT) in patients with AR.

Methods  The total symptom score and the levels of total immunoglobulin E (IgE) and IL-33 were determined in the serum of 10 non-allergic healthy controls and 45 patients with AR who were equally divided into 3 groups: GI (patients did not receive IT), GII (patients had received IT for 6 months) and GIII (patients had received IT for 2 years).

Results  There was a significantly higher concentration of IgE and IL-33 in the serum of patients with AR than in that of non-allergic patients. Furthermore, serum level of IL-33 decreased significantly after pollen IT. But, there was no significant reduction in the serum level of IL-33 between GII and GIII patients.

Conclusion  Our results show a clinical improvement associated with a decrease in serum level of IL-33 after pollen IT.

Cost-effectiveness of grass pollen SCIT compared with SLIT and symptomatic treatment

Background

Whereas specific immunotherapy (SIT) has already been shown to be cost-effective in the treatment of allergic rhinitis compared with symptomatic treatment, only a small number of investigations have compared sublingual (SLIT) and subcutaneous (SCIT) immunotherapeutic approaches. This analysis discusses the cost-effectiveness of SCIT compared with SLIT and a symptomatic treatment modality. At the same time, particular attention is paid to preparation-specific characteristics.

Methods

The investigation is based on a previously published health economic model calculation. A Markov model, with predefined disease stages and a time period of 9 years, formed the basis of the analysis. The data on specific SCIT (Allergovit®) and SLIT (Oralair®) preparations required for the calculation were adjusted for the present analysis. Quality-adjusted life years (QALYs) based on symptom scores were calculated as the endpoint for effectiveness. Furthermore, the total costs and cost effectiveness of SCIT were determined. Model uncertainties were estimated by means of additional sensitivity analyses.

Results

With regard to effectiveness, both the SCIT and SLIT preparations proved superior compared to symptomatic treatment. Although more expensive, SIT seem to be cost-effective. A direct comparison of SCIT (Allergovit®) and SLIT (Oralair®) showed lower total costs for SCIT treatment over the study period (SCIT 1159 € versus SLIT 1322 €) and improved effectiveness (SCIT 7.112 QALYs versus SLIT 7.060 QALYs).

Discussion

SIT represents a cost-effective treatment option for patients with allergic rhinitis compared with symptomatic treatment. The comparison of SCIT (Allergovit®) and SLIT (Oralair®) showed SCIT to be predominant and cost-effective, due in particular to somewhat greater patient compliance and lower drug costs. It also became evident that, as far as possible, product-specific model variables are required for an economic evaluation of SIT treatment.

High-dose sublingual immunotherapy in patients with uncontrolled allergic rhinitis sensitized to pollen: a real-life clinical study

BACKGROUND

High-dose pollen sublingual immunotherapy (SLIT) is indicated in patients with moderate to severe allergic rhinitis (AR), especially those who are unable to control their disease with pharmacotherapy. We explore the use of high-dose SLIT in patients with severe AR and sensitized to pollen, in real-life clinical practice. We also analyzed the effect on asthma.

METHODS

This was a prospective observational study conducted at the Allergy outpatient clinic at Hotel Dieu de France Hospital (HDF), Beirut, Lebanon. The cohort, composed of 118 patients between 7 and 55 years old, was regularly evaluated at inclusion, at 12 months, and at 36 months. Fifty-five percent of AR patients had associated controlled asthma. Patients received a standardized pollen extract (Staloral 300IR). The pollen combination was 1 to 3 pollens, the most commonly used were Parietaria judaica, Cupressaceae, 5 grasses, and Oleaceae. In a previous study, those were the main allergenic pollens correlated to AR in the same population. Global assessment of the effect of SLIT was measured using a rhinitis total symptom score (RTSS), a rhinitis medication consumption score (RMCS), a global asthma score (ASS), and an asthma medication consumption score (AMCS).

RESULTS

Using a t test we found that the average scores at inclusion, 12 months, and 36 months, respectively, were as follows: RTSS: 31.32, 16.39 (p < 0.041), and 13.35 (p < 0.041); RMCS: 6.96, 1.96 (p < 0.0162), and 1.61 (p < 0.0162); ASS: 4.62, 1.96 (p < 0.0005), and 1.33 (p < 0.0005); and AMCS: 2.35, 0.78 (p < 0.0005), and 0.7 (p < 0.0005).

CONCLUSION

Our study showed favorable results of SLIT to aeroallergens in patients with uncontrolled AR. The effect is also applicable to the subgroup of patients suffering from concomitant, controlled asthma.

Patient initiation and persistence with allergen immunotherapy

BACKGROUND

Allergen immunotherapy (AIT) is advised for patients with allergic rhinitis who remain symptomatic despite the use of pharmacotherapy and allergen avoidance. Several factors influence the decision to initiate and complete the AIT regimen.

OBJECTIVE

To evaluate patient initiation and persistence with subcutaneous and sublingual immunotherapies (SCIT and SLIT) according to physician recommendation.

METHODS

A retrospective review of electronic health records of patients with allergic rhinitis for whom AIT was recommended was conducted in a large private allergy practice in Pennsylvania.

RESULTS

Of 8,790 patients advised to consider AIT, 36.2% initiated AIT (57% adults, 43% children); 78% chose SCIT and 22% chose SLIT drops. Election of AIT was significantly associated with select comorbidities, specifically chronic sinusitis (8.1% for AIT vs 10% for no AIT), allergic conjunctivitis (12.5% for AIT vs 18.5% for no AIT), and asthma (33.8% for AIT vs 37.4% for no AIT; P < .05). Choice of SCIT vs SLIT drops was significantly associated with older age, female sex, select comorbidities, and more allergy medications at initiation (P < .05). Of adults, 30.2% completed at least 3 years of recommended treatment. Median time on treatment was longer for adults on SCIT vs SLIT drops (3 vs 1.6 years). Similarly, 35.4% of children completed treatment, with a longer median time on treatment for SCIT (4.7 years) vs SLIT drops (3.5 years).

CONCLUSION

A minority of patients initiated AIT according to allergist recommendation and a subset of these patients completed therapy. AIT might be an underused option that could benefit patients unable to manage allergic rhinitis symptoms by other means.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01549340.

Sublingual immunotherapy and quality of life

PURPOSE OF REVIEW

Sublingual immunotherapy (SLIT) has been shown to be a new and promising treatment for people with various allergic syndromes. Several studies have examined its efficacy. However, significantly fewer investigations have explored its specific impact on the patient's quality of life (QOL).

RECENT FINDINGS

SLIT has an excellent safety profile, superior in many ways to subcutaneous immunotherapy (SCIT). Additionally, SLIT significantly decreases the use of allergy medications, as well as decreasing the money spent on allergy symptom control. Finally, SLIT has been shown to improve the patient's QOL when compared to placebo or even second-generation antihistamines.

SUMMARY

Increasing data support the use of SLIT as a well tolerated, cost-effective, and time-efficient modality for the treatment of multiple allergic syndromes. However, additional studies are needed, particularly QOL studies which compare SLIT to the FDA-approved SCIT.

Perception and practice of sublingual immunotherapy among practicing allergists in the United States: a follow-up survey

BACKGROUND

Limited information regarding current trends of sublingual immunotherapy (SLIT) use, perception, and prescribing patterns among allergists in the United States is available.

OBJECTIVE

To obtain information about current allergist perception and practice of SLIT compared with 2007.

METHODS

On behalf of the American College of Allergy, Asthma and Immunology (ACAAI) Immunotherapy and Diagnostics Committee, an electronic survey was sent to all practicing allergists of the ACAAI in August 2011.

RESULTS

Fifty-nine of 519 US respondents (11.4%) reported experience using SLIT compared with 45 of 766 (5.9%) in 2007 (P < .001). Lack of Food and Drug Administration (FDA) approval was the primary barrier in using SLIT in the United States among 469 of 520 respondents (90.2%), which was increased from 471 of 763 (61.7%) in 2007 (P < .001). Among US respondents, 344 of 516 (66.7%) believed that SLIT was safer than subcutaneous immunotherapy (SCIT) compared with 554 of 755 (73.4%) in 2007 (P < .01). In total, 22 of 51 SLIT users (43.1%) reported SLIT efficacy equal to or even greater than SCIT, which was similar to 21 of 38 (55.3%) reported in 2007 (P < .36).

CONCLUSION

Rates of SLIT use reported by US respondents have nearly doubled in the last 4 years, with 11.4% of US respondents reporting SLIT use. Because the greatest barrier to SLIT use in the United States is the lack of FDA approval, it is anticipated that once an FDA-approved product is available, there will be widespread use of SLIT in the United States. Practice guidelines, which include effective dosages and schedules, will be critical to the broad implementation of SLIT in the United States.

Allergen-specific immunotherapy for pediatric asthma and rhinoconjunctivitis: a systematic review

BACKGROUND AND OBJECTIVE

Subcutaneous immunotherapy (SCIT) is approved in the United States for the treatment of pediatric asthma and rhinitis; sublingual immunotherapy (SLIT) does not have regulatory approval but is used in clinical practice. The objective of this study was to systematically review the evidence regarding the efficacy and safety of SCIT and SLIT for the treatment of pediatric asthma and allergic rhinoconjunctivitis.

METHODS

Two independent reviewers selected articles for inclusion, extracted data, and graded the strength of evidence for each clinical outcome. All studies were randomized controlled trials of children with allergic asthma or rhinoconjunctivitis treated with SCIT or an aqueous formulation of SLIT. Data sources were Medline, Embase, LILACS, CENTRAL, and the Cochrane Central Register of Controlled Trials through May 2012.

RESULTS

In 13 trials, 920 children received SCIT or usual care; in 18 studies, 1583 children received SLIT or usual care. Three studies compared SCIT with SLIT head-to-head in 135 children. The strength of evidence is moderate that SCIT improves asthma and rhinitis symptoms and low that SCIT improves conjunctivitis symptoms and asthma medication scores. Strength of evidence is high that SLIT improves asthma symptoms and moderate that SLIT improves rhinitis and conjunctivitis symptoms and decreases medication usage. The evidence is low to support SCIT over SLIT for improving asthma or rhinitis symptoms or medication usage. Local reactions were frequent with SCIT and SLIT. There was 1 report of anaphylaxis with SCIT.

CONCLUSIONS

Evidence supports the efficacy of both SCIT and SLIT for the treatment of asthma and rhinitis in children.

Specific immunotherapy with allergens: an important tool in the treatment of the allergic diseases

Immunotherapy was introduced 100 years ago and still is the only treatment that modifies the course of allergic diseases. The success of its use depends on correct indications, use of standardized extracts and monitoring the therapeutic response.

Efficacy of subcutaneous and sublingual immunotherapy with grass allergens for seasonal allergic rhinitis: a meta-analysis-based comparison

BACKGROUND

Subcutaneous (SCIT) and sublingual (SLIT) immunotherapy are the 2 most prescribed routes for administering allergen-specific immunotherapy. They were shown to be effective in control of symptoms and in reducing rescue medication use in patients with allergic diseases, but their effectiveness has to be balanced against side effects. In recent years, SLIT has been increasingly prescribed, instead of SCIT, because of improved safety and easy administration.

OBJECTIVE

We assessed which route is the most effective in the treatment of patients with seasonal allergic rhinitis to grass pollen.

METHODS

An indirect meta-analysis-based comparison between SCIT and SLIT was performed. Treatment efficacy was determined as the standardized mean difference (SMD) in symptom and medication scores obtained with active treatment, SCIT or SLIT, compared with placebo. Studies were included if they were double-blind randomized controlled trials comparing SCIT or SLIT with placebo. Thirty-six randomized controlled trials (3014 patients; 2768 controls) were analyzed.

RESULTS

The overall effect size of SCIT for symptom score (SMD, -0.92; 95%CI, -1.26 to -0.58) was significantly higher than SLIT, both administered via drops (SMD, -0.25; 95% CI, -0.45 to -0.05) and tablets (SMD, -0.40; 95%CI, -0.54 to -0.27). Similar results were reported for medication score (SCIT: SMD, -0.58; 95% CI, -0.86 to -0.30. SLIT drops: SMD, -0.37; 95% CI, -0.74 to -0.00. SLIT tablets SMD, -0.30; 95% CI, -0.44 to -0.16).

CONCLUSIONS

Our results provide indirect but solid evidence that SCIT is more effective than SLIT in controlling symptoms and in reducing the use of antiallergic medications in seasonal allergic rhinoconjuntivitis to grass pollen.

Perspectives on allergen-specific immunotherapy in childhood: an EAACI position statement

This article is the result of consensus reached by a working group of clinical experts in paediatric allergology as well as representatives from an ethical committee and the European Medicine Agency (EMA). The manuscript covers clinical, scientific, regulatory and ethical perspectives on allergen-specific immunotherapy in childhood. Unmet needs are identified. To fill the gaps and to bridge the different points of view, recommendations are made to researchers, to scientific and patient organizations and to regulators and ethical committees. Working together for the benefit of the community is essential. The European Academy of Allergy and Clinical Immunology (EAACI) serves as the platform of such cooperation.

Allergen-specific immunotherapy provides immediate, long-term and preventive clinical effects in children and adults: the effects of immunotherapy can be categorised by level of benefit -the centenary of allergen specific subcutaneous immunotherapy

Allergen Specific Immunotherapy (SIT) for respiratory allergic diseases is able to significantly improve symptoms as well as reduce the need for symptomatic medication, but SIT also has the capacity for long-term clinical effects and plays a protective role against the development of further allergies and symptoms. The treatment acts on basic immunological mechanisms, and has the potential to change the pathological allergic immune response. In this paper we discuss some of the most important achievements in the documentation of the benefits of immunotherapy, over the last 2 decades, which have marked a period of extensive research on the clinical effects and immunological background of the mechanisms involved. The outcome of immunotherapy is described as different levels of benefit from early reduction in symptoms over progressive clinical effects during treatment to long-term effects after discontinuation of the treatment and prevention of asthma. The efficacy of SIT increases the longer it is continued and immunological changes lead to potential long-term benefits. SIT alone and not the symptomatic treatment nor other avoidance measures has so far been documented as the therapy with long-term or preventive potential. The allergic condition is driven by a subset of T-helper lymphocytes (Th2), which are characterised by the production of cytokines like IL-4, and IL-5. Immunological changes following SIT lead to potential curative effects. One mechanism whereby immunotherapy suppresses the allergic response is through increased production of IgG4 antibodies. Induction of specific IgG4 is able to influence the allergic response in different ways and is related to immunological effector mechanisms, also responsible for the reduced late phase hyperreactivity and ongoing allergic inflammation. SIT is the only treatment which interferes with the basic pathophysiological mechanisms of the allergic disease, thereby creating the potential for changes in the long-term prognosis of respiratory allergy. SIT should not only be recognised as first-line therapeutic treatment for allergic rhinoconjunctivitis but also as secondary preventive treatment for respiratory allergic diseases.