Immunotherapy for allergic rhinitis

The effect of allergen immunotherapy in the onset of new sensitizations: a meta-analysis

BACKGROUND

Although the preventive efficacy of allergen immunotherapy (AIT) in the onset of new allergen sensitizations has been asserted by many reviews, position papers, and consensus conferences, the evidence available is from only 3 studies. The objective of this work was a systematic review to evaluate the preventive efficacy of AIT in the onset of new allergen sensitizations. The end-point was the risk difference (RD) in the onset of new allergen sensitizations between patients treated with AIT and pharmacotherapy.

METHODS

Computerized bibliographic searches of MEDLINE, EMBASE, and the Cochrane Library (until November 30th, 2016) were done. Random-effects and fixed-effects model meta-analyses were performed. Randomized controlled trials or observational studies comparing children treated with AIT with house dust mite (HDM) to subjects who did not receive AIT, with a long-term observation period (at least 3 years including treatment and follow-up) have been included.

RESULTS

Eight studies totaling 721 children (390 treated with AIT and 331 with pharmacotherapy) met the inclusion criteria. The risk of bias was high. Low evidence supports the conclusion that AIT prevents the onset of new allergen sensitizations, with 3 of 8 studies reporting a reduction in the onset of new sensitizations in patients treated with AIT vs pharmacotherapy. Our meta-analysis found no difference between AIT and pharmacotherapy, with high heterogeneity (RD, -0.10; 95% confidence interval [CI], -0.31 to 0.11; p = 0.32; I² = 91.4%).

CONCLUSION

The data of this systematic review do not support a preventive effect in the onset of new allergen sensitizations, in children treated with AIT in comparison with those treated with pharmacotherapy.

Efficacy of allergen immunotherapy in reducing the likelihood of developing new allergen sensitizations: a systematic review

BACKGROUND

Guidelines and position papers indicate that allergen immunotherapy (AIT) is the only disease-modifying treatment, including prevention of the onset of new allergen sensitizations. However, this preventive effect was shown by only a few observational studies. Our aim was to systematically review the efficacy of AIT in preventing the onset of new allergen sensitizations.

METHODS

Computerized bibliographic searches of Medline, EMBASE, and the Cochrane Library (through June 2015) were supplemented with manual searches of reference lists. Observational studies or randomized controlled trials with a long-term observation period were included. Paired reviewers extracted data about study characteristics and assessed biases. The end point was the risk difference in the onset of new allergen sensitizations between patients treated with AIT and pharmacotherapy. The strength of the evidence was graded based on the risk of bias, consistency, and magnitude of effect, according to the GRADE Working Group's guide.

RESULTS

Eighteen studies (1049 children, 10 057 adults) met the inclusion criteria. The risk of bias was high in all but one study. Low evidence supports the position that AIT prevents the onset of new allergen sensitizations, with 10 of 18 studies reporting a reduction in the onset of new sensitizations in patients treated with AIT vs placebo. Small studies and studies with a shorter follow-up showed the highest benefit of AIT.

CONCLUSIONS

The overall evidence provides a low-grade level of the evidence supporting the efficacy of AIT in preventing the onset of new allergen sensitizations, but high-quality studies could change this estimate.

Effect of 2 Years of Treatment With Sublingual Grass Pollen Immunotherapy on Nasal Response to Allergen Challenge at 3 Years Among Patients With Moderate to Severe Seasonal Allergic Rhinitis: The GRASS Randomized Clinical Trial

IMPORTANCE

Sublingual immunotherapy and subcutaneous immunotherapy are effective in seasonal allergic rhinitis. Three years of continuous treatment with subcutaneous immunotherapy and sublingual immunotherapy has been shown to improve symptoms for at least 2 years following discontinuation of treatment.

OBJECTIVE

To assess whether 2 years of treatment with grass pollen sublingual immunotherapy, compared with placebo, provides improved nasal response to allergen challenge at 3-year follow-up.

DESIGN, SETTING, AND PARTICIPANTS

A randomized double-blind, placebo-controlled, 3-parallel-group study performed in a single academic center, Imperial College London, of adult patients with moderate to severe seasonal allergic rhinitis (interfering with usual daily activities or sleep). First enrollment was March 2011, last follow-up was February 2015.

INTERVENTIONS

Thirty-six participants received 2 years of sublingual immunotherapy (daily tablets containing 15 µg of major allergen Phleum p 5 and monthly placebo injections), 36 received subcutaneous immunotherapy (monthly injections containing 20 µg of Phleum p 5 and daily placebo tablets) and 34 received matched double-placebo. Nasal allergen challenge was performed before treatment, at 1 and 2 years of treatment, and at 3 years (1 year after treatment discontinuation).

MAIN OUTCOMES AND MEASURES

Total nasal symptom scores (TNSS; range; 0 [best] to 12 [worst]) were recorded between 0 and 10 hours after challenge. The minimum clinically important difference for change in TNSS within an individual is 1.08. The primary outcome was TNSS comparing sublingual immunotherapy vs placebo at year 3. Subcutaneous immunotherapy was included as a positive control. The study was not powered to compare sublingual immunotherapy with subcutaneous immunotherapy.

RESULTS

Among 106 randomized participants (mean age, 33.5 years; 34 women [32.1%]), 92 completed the study at 3 years. In the intent-to-treat population, mean TNSS score for the sublingual immunotherapy group was 6.36 (95% CI, 5.76 to 6.96) at pretreatment and 4.73 (95% CI, 3.97 to 5.48) at 3 years, and for the placebo group, the score was 6.06 (95% CI, 5.23 to 6.88) at pretreatment and 4.81 (95% CI, 3.97 to 5.65) at 3 years. The between-group difference (adjusted for baseline) was -0.18 (95% CI, -1.25 to 0.90; [P = .75]).

CONCLUSIONS AND RELEVANCE

Among patients with moderate to severe seasonal allergic rhinitis, 2 years of sublingual grass pollen immunotherapy was not significantly different from placebo in improving the nasal response to allergen challenge at 3-year follow-up.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01335139; EudraCT Number: 2010-023536-16.

An update on allergen immunotherapy

Allergen-specific immunotherapy (AIT) has been used to treat allergic diseases for over a century. It is the only treatment that addresses immune dysfunction underlying allergic responses rather than simply treating symptoms or suppressing inflammation. Its safety and efficacy in allergic rhinitis, asthma and insect allergy has been documented in a number of systematic reviews but its cost effectiveness is less clear. AIT reduces symptoms and requirement for medication, while improving quality of life. Further, the effect continues for years after discontinuation of treatment. However, evidence regarding cost effectiveness is limited. During AIT, allergen extracts are administered through a subcutaneous or sublingual route for 3-5 years. Subcutaneous immunotherapy is more effective in inducing long-term remission but systemic reactions do occur occasionally. Sublingual immunotherapy is safer and more convenient for the patient but evidence regarding its long-term efficacy is patchy. AIT is used widely in western Europe and the USA. In the UK, subcutaneous immunotherapy is often used for bee and wasp allergy, while both subcutaneous and sublingual immunotherapies are used for severe allergic rhinitis and occasionally for house dust mite and pet allergies. In conclusion, AIT is safe and effective and should be considered as a treatment option for those with allergic diseases.

Evidence in immunotherapy for paediatric respiratory allergy: Advances and recommendations

Allergic respiratory diseases are major health problems in paediatric population due their high level of prevalence and chronicity, and to their relevance in the costs and quality of life. One of the most important risk factors for the development of airway diseases in children and adolescents is atopy. The mainstays for the treatment of these diseases are avoiding allergens, controlling symptoms, and preventing them through sustained desensitization by allergen immunotherapy (AIT). AIT is a treatment option that consists in the administration of increasing amounts of allergens to modify the biological response to them, inducing long-term tolerance even after treatment has ended. This treatment approach has shown to decrease symptoms and improve quality of life, becoming cost effective for a large number of patients. In addition, it is considered the only treatment that can influence the natural course of the disease by targeting the cause of the allergic inflammatory response. The aim of this publication is to reflect the advances of AIT in the diagnosis and treatment of allergic respiratory diseases in children and adolescents reviewing articles published since 2000, establishing evidence categories to support the strength of the recommendations based on evidence. The first part of the article covers the prerequisite issues to understand how AIT is effective, such as the correct etiologic and clinical diagnosis of allergic respiratory diseases. Following this, the article outlines the advancements in understanding the mechanisms by which AIT achieve immune tolerance to allergens. Administration routes, treatment regimens, dose and duration, efficacy, safety, and factors associated with adherence are also reviewed. Finally, the article reviews future advances in the research of AIT.

Allergen immunotherapy for allergic rhinoconjunctivitis: protocol for a systematic review

Background

The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines for Allergen Immunotherapy (AIT) for the Management of Allergic Rhinoconjunctivitis. We seek to critically assess the effectiveness, cost-effectiveness and safety of AIT in the management of allergic rhinoconjunctivitis.

Methods

We will undertake a systematic review, which will involve searching international biomedical databases for published, in progress and unpublished evidence. Studies will be independently screened against pre-defined eligibility criteria and critically appraised using established instruments. Data will be descriptively and, if possible and appropriate, quantitatively synthesised.

Conclusion

The findings from this review will be used to inform the development of recommendations for EAACI’s Guidelines on AIT.

The efficiency of peptide immunotherapy for respiratory allergy

Allergen immunotherapy (AIT) was introduced more than a century ago and is yet the only disease-modifying treatment for allergy. AIT is currently conducted with whole allergen extracts and several studies clearly support its efficacy in the treatment of respiratory allergies, however the need for a long treatment - that affects costs and patients compliance - and possible IgE-mediated adverse events are still unresolved issues. Peptide immunotherapy is based on the use of short synthetic peptides which represent major T-cell epitopes of the allergen with markedly reduced ability to cross-link IgE and activate mast cells and basophils. Data from clinical trials confirmed the efficacy and tolerability of peptide immunotherapy in patients with cat allergy, with a sustained clinical effect after a short course treatment. Peptide therapy is a promising safe and effective new specific treatment for allergy to be developed for the most important allergens causing rhinitis or asthma.

Randomized dose–response study of subcutaneous immunotherapy with a Dermatophagoides pteronyssinus extract in patients with respiratory allergy

Aim: To evaluate the efficacy of Dermatophagoides pteronyssinus (DPT) subcutaneous immunotherapy in allergic rhinoconjunctivitis patients. Patients & methods: This 17-week double-blind study randomized 136 patients (95 evaluable) to five dose groups of DPT depot extract (0.0625–0.75 skin prick test [SPT] units) or placebo, administered in a six updosing schedule. Results: A dose–response was observed for clinical efficacy (allergen concentration needed to induce a positive nasal provocation test response from baseline to final visit) and safety (adverse reactions). Local and systemic reactions occurred with 14.8 and 6.4% of administered doses, respectively; a single anaphylactic reaction occurred in each of Groups 3, 4 and 5 (0.3% of doses). Conclusion: The risk–benefit profile appeared most favorable with a DPT dose of 0.125 SPT units.

Orphan immunotherapies for allergic diseases

OBJECTIVE

As confirmed by systematic reviews and meta-analyses, allergen immunotherapy is clinically effective in the treatment of allergic diseases. In particular, subcutaneous immunotherapy is a pivotal treatment in patients with severe reactions to Hymenoptera venom, whereas subcutaneous immunotherapy and sublingual immunotherapy are indicated in the treatment of allergic rhinitis and asthma by inhalant allergens. Other allergies related to animal dander (other than cat, which is the most studied), such as dog, molds, occupational allergens, and insects, have also been recognized. For these allergens, immunotherapy is poorly studied and often unavailable. Thus, use of the term orphan immunotherapies is appropriate.

DATA SOURCES

We used MEDLINE to search the medical literature for English-language articles.

STUDY SELECTION

Randomized, controlled, masked studies for orphan immunotherapies were selected. In the remaining cases, the available reports were described.

RESULTS

The literature on food desensitization is abundant, but for other orphan allergens, such as mosquito, Argas reflexus, dog, or occupational allergens, there are only a few studies, and most are small studies or case reports.

CONCLUSION

Orphan immunotherapy is associated with insufficient evidence of efficacy from controlled trials, an erroneous belief of the limited importance of some allergen sources, and the unlikelihood for producers to have a profit in making commercially available extracts (with an expensive process for registration) to be used in few patients. It should be taken into consideration that adequate preparations should be available also for orphan allergens.

Pediatric investigation plans for specific immunotherapy: Questionable contributions to childhood health

Allergen-specific immunotherapy (SIT) is the only disease-modifying treatment for children, adolescents, and adults with allergic diseases. The EU has a combined system of national and EU-wide marketing authorization for all medicines. Germany introduced a new therapy allergen ordinance in 2008. Allergen products manufacturers had to apply for marketing authorization application for the major allergen groups (grass group, birch group, mites group, bee/wasp venom). Due to the EU pediatric regulation, in force since 2007, manufacturers had also to submit a pediatric investigation plan (PIP) for each allergen product. We investigated the allergic rhinoconjunctivitis (ARC) standard PIP, developed jointly by the European Medicines Agency (EMA) and the German Paul Ehrlich Institut (PEI). We analyzed the 118 EMA PIP decisions, looked for SIT trials in children in www.clinicaltrials.gov, and further analyzed EMA/EU justifications. The PIPs request a 1-year dose-finding study in adults, a 5-year placebo-controlled (PC) efficacy & safety (E&S) study in adults, and a 5-year PC E&S study in children. Fifty-eight PIP development programs will have to be performed until 2031. But children benefit even more from SIT for ARC than adults. There is no convincing medical/scientific justification for PC E&S studies in children in the relevant EMA documents. The PIP requirement to withhold effective treatment to thousands of children in the placebo group over a 5-year period raises profound concerns. The EMA justifications are formalistic and lack scientific foundation. A critical academic review of the ARC PIPs and the entire PIP system is urgently needed.

Guiding principles of sublingual immunotherapy for allergic rhinitis in Japanese patients

OBJECTIVE

Sublingual immunotherapy (SLIT) appears to offer practical advantages for the treatment of allergic rhinitis (AR). Based on a review of the scientific literature, we present recommendations as guiding principles to administer SLIT safely.

METHODS

Clinical questions concerning SLIT were prepared. Literature published between January 2003 and December 2012 was searched from PubMed, the Cochrane Library, and Japana Centra Revuo Medicina. Qualified studies were analyzed and the results were evaluated, consolidated, and codified. We answered 17 clinical questions and, based on this, presented evidence-based recommendations.

RESULTS

Sublingual immunotherapy improved symptoms (e.g., quality of life [QOL]) and reduced medication scores in seasonal AR and perennial AR. Most SLIT-induced adverse effects were local oral reactions, although systemic adverse effects such as gastrointestinal symptoms, urticaria, and asthma are occasionally reported. There have been no reports of lethal anaphylactic reactions by SLIT. When SLIT is continued for 3-4 years, its effect persists long after discontinuation.

CONCLUSION

A correct diagnosis of AR and sufficient informed consent from patients are required before initiating SLIT. Sublingual immunotherapy should be continued for 3 years or longer. The initial administration of SLIT during the uptitration of an allergen vaccine and the general condition of patients are critical for the safe performance of SLIT.

Allergy immunotherapy: the future of allergy treatment

Allergic respiratory disease represents a significant and expanding health problem worldwide. Allergic symptoms, such as asthma and hay fever, cause sleep impairment and reduce school and work performance. The cost to society is substantial. Allergen avoidance and pharmacotherapy cannot control the disease. Only allergy immunotherapy has disease-modifying potential and should be included in optimal treatment strategies. Allergy immunotherapy was first administered as subcutaneous injections and has been practiced for the past 100 years or so. Recently, tablet-based sublingual allergy immunotherapy (SLIT) was introduced with comprehensive clinical documentation. SLIT tablets represent a more patient-friendly concept because they can be used for self-treatment at home.

Clinical contraindications to allergen immunotherapy: an EAACI position paper

Clinical indications for allergen immunotherapy (AIT) in respiratory and Hymenoptera venom allergy are well established; however, clinical contraindications to AIT are not always well documented. There are some discrepancies when classifying clinical contraindications for different forms of AIT as 'absolute' or 'relative'. EAACI Task Force on 'Contraindications to AIT' was created to evaluate and review current literature on clinical contraindications, and to update recommendations for both sublingual and subcutaneous AIT for respiratory and venom immunotherapy. An extensive review of the literature was performed on the use of AIT in asthma, autoimmune disorders, malignant neoplasias, cardiovascular diseases, acquired immunodeficiencies and other chronic diseases (including mental disorders), in patients treated with β-blockers, ACE inhibitors or monoamine oxidase inhibitors, in children under 5 years of age, during pregnancy and in patients with poor compliance. Each topic was addressed by the following three questions: (1) Are there any negative effects of AIT on this concomitant condition/disease? (2) Are more frequent or more severe AIT-related side-effects expected? and (3) Is AIT expected to be less efficacious? The evidence, for the evaluation of these clinical conditions as contraindications, was limited, and most of the conclusions were based on case reports. Based on an extended literature research, recommendations for each medical condition assessed are provided. The final decision on the administration of AIT should be based on individual evaluation of any medical condition and a risk/benefit assessment for each patient.

Specific immunotherapy for allergic rhinitis in children

PURPOSE OF REVIEW

Allergic rhinitis is a highly prevalent inflammatory disease affecting 20-40% of the children worldwide. Allergen-specific immunotherapy (SIT) is an effective treatment for allergic rhinitis. This article reviews the recent advances in SIT for children.

RECENT FINDINGS

In current clinical practice, immunotherapy is delivered as either subcutaneous immunotherapy or sublingual immunotherapy (SLIT). Most meta-analyses and reviews concluded a trend that subcutaneous immunotherapy was better than SLIT in reducing symptoms of allergic rhinitis and rescue medication use, however, SLIT has a better safety profile than subcutaneous immunotherapy. Additionally, the absence of pain on administration of therapy is a character of SLIT, which is well suited for children. T regulatory cells, especially Tr1 cells that secrete interleukin-10 and induce production of immunoglobulin G4, play a role during SIT.

SUMMARY

Although there is substantial evidence for effectiveness of both subcutaneous immunotherapy and SLIT, safer and more effective SIT approaches are needed. New approaches to improve SIT include omalizumab pretreatment, use of recombinant allergens, and alternate routes of administration.

Optimal management of allergic rhinitis

Allergic rhinitis (AR), the most common chronic disease in childhood is often ignored, misdiagnosed and/or mistreated. Undertreated AR impairs quality of life, exacerbates asthma and is a major factor in asthma development. It can involve the nose itself, as well as the organs connected with the nose manifesting a variety of symptoms. Evidence-based guidelines for AR therapy improve disease control. Recently, paediatric AR guidelines have been published by the European Academy of Allergy and Clinical Immunology and are available online, as are a patient care pathway for children with AR and asthma from the Royal College of Paediatrics and Child Health. Management involves diagnosis, followed by avoidance of relevant allergens, with additional pharmacotherapy needed for most sufferers. This ranges, according to severity, from saline sprays, through non-sedating antihistamines, oral or topical, with minimally bioavailable intranasal corticosteroids for moderate/severe disease, possibly plus additional antihistamine or antileukotriene. The concept of rhinitis control is emerging, but there is no universally accepted definition. Where pharmacotherapy fails, allergen-specific immunotherapy, which is uniquely able to alter long-term disease outcomes, should be considered. The subcutaneous form (subcutaneous immunotherapy) in children has been underused because of concerns regarding safety and acceptability of injections. Sublingual immunotherapy is both efficacious and safe for grass pollen allergy. Further studies on other allergens in children are needed. Patient, carer and practitioner education into AR and its treatment are a vital part of management.

Allergen immunotherapy, routes of administration and cytokine networks: an update

Allergen immunotherapy is a disease-modifying therapy, effective for the treatment of allergic rhinitis, allergic asthma, conjunctivitis or stinging insect allergy. Allergen immunotherapy involves the administration of increasing doses of allergens with the aim of ameliorating the allergic response. Although precise underlying mechanisms of the induction of immune tolerance remain unclear, immunotherapy has been associated with the induction of distinct subsets of Tregs that eventually lead to peripheral tolerance by inducing a deviation from Th2 to Th1 immune responses. This review focuses on the current knowledge of the mechanisms of immunotherapy in relationship to different routes of administration and also provides a unifying view.

Systematic review of immunotherapy for chronic rhinosinusitis

BACKGROUND

Immunotherapy (IT) has been well established as an effective treatment for allergic rhinitis (AR), but little is known about the benefits of IT on clinical outcomes of comorbid chronic rhinosinusitis (CRS). The goal of this publication is to systematically review the literature regarding outcomes of IT in patients with atopic CRS.

METHODS

A systematic review of the literature was conducted including studies that assessed the efficacy of IT on clinical outcome measures in CRS including without polyp, with polyp, and allergic fungal rhinosinusitis subgroups. Excluded articles were those only reporting outcomes specific to asthma or AR.

RESULTS

Seven studies met the inclusion and exclusion criteria for this review, none of which were randomized controlled trials. Generally, symptom scores improved in patients treated with IT when compared with baseline data and control patients. Objective endoscopic exam measures improved with IT treatment in short-term studies. Significant improvements were observed in radiographic assessments, and there was a decreased necessity for revision surgery, interventional office visits, and intranasal and oral steroid use.

CONCLUSION

Conclusions are limited by the paucity of available data on the efficacy of IT for treating CRS-specific outcome measures. There is weak evidence to support the use of IT as an adjunctive treatment in CRS patients, particularly in the postoperative period.

[Specific immunotherapy]

SCIT (subcutaneous immunotherapy) and SLIT (sublingual immunotherapy) are the only routinely available therapies, which modify allergic diseases sustainably. The ongoing reduction of symptoms and the lower need of symptomatic medication are able to improve the quality of life over a long period of time. However, allergic patients are underprovided due to low use of SIT (specific immunotherapy). After thorough diagnostic workup, the indication has to be checked carefully especially in patients with allergic rhinitis and allergic asthma, to insure that SIT is standard therapy. Allergen extracts are manufacturer-specific preparations, therefore their effects cannot be compared directly, just as SCIT and SLIT efficacy cannot be compared directly. In general, preparations with proven efficacy and safety profile should be preferred. Allergens listed in the TAV (Therapeutic Allergen Regulation) fulfill these requirements. However, it is important to ensure adherence for 3 years of therapy, independent of the route of application. SIT has proven socioeconomic benefit already after a short time of therapy.

Arguing the misconceptions in allergen-specific immunotherapy

Allergen immunotherapy (AIT) has a clear evidence of efficacy and safety, as shown by a number of meta-analyses. However, a number of issues limit the use of AIT, many of them being not actually supported by solid data from the literature. In particular, several contraindications to AIT deserve to be argued, being needed to accurately balance in single cases the benefits versus the disadvantages. This concerns comorbidities, such as autoimmune diseases and malignancies, concomitant drug treatments, particularly β-blockers and angiotensin-converting enzyme inhibitors, pregnancy, patient's age, the severity of asthma, allergen polysensitization and the period of starting the treatment. Another important aspect producing misconceptions on AIT is the quality of the allergen extracts, because currently a patient with respiratory allergy to a given source may be prescribed to treat his allergyby products with very different quality. Improving characterization and standardization of allergen extracts will pave the way to the general acknowledgment of AIT as an effective treatment.

Clinical and cytokine responses to house dust mite sublingual immunotherapy

BACKGROUND

Cytokine responses accompanying sublingual immunotherapy (SLIT) responder phenotypes have not previously been reported.

OBJECTIVE

To investigate clinical and cytokine responses of house dust mite (HDM) sensitive patients with allergic rhinitis receiving HDM SLIT or placebo for 2 years.

METHODS

Sixty adults were randomized to receive SLIT or placebo. Clinical symptoms were measured using the Total 5 Symptom Score (TSS5) and Juniper Rhinitis Quality of Life Questionnaire. HDM specific IgE, IgG, skin prick tests, and HDM-stimulated release of interleukin (IL) 5 and interferon γ (IFN-γ) in peripheral blood mononuclear cells was studied at 0, 6, 12, and 24 months and IL-13, IL-4, and IL-10 at 0 and 24 months.

RESULTS

A total of 32 of 39 SLIT and 16 of 21 placebo patients completed the study. There was significant clinical improvement in both the SLIT and placebo groups. Median T5SS decreased from 14.75 to 5.25 in the SLIT group (P < .001) and 12.7 to 6.0 in the placebo group (P = .003). The median quality-of-life score also decreased in the SLIT group (P < .001) and the placebo group (P < .001). A subgroup analysis of patients found a 60% or greater improvement (on the T5SS and the Juniper Rhinitis Quality of Life Questionnaire) in the good responders group and a 30% to 59% improvement or no improvement in the intermediate responders group. This subgroup analysis also found more good responders in the SLIT group (47%) compared with the placebo group (25%; P = .07). Significant decreases in the IL-5/IFN-γ (P < .001), IL-13/IFN-γ (P < .001), and IL-4/IFN-γ (P = .03) ratios were found in the combined good clinical improvement group at 24 months.

CONCLUSION

A good clinical response (≥60% improvement in both TSS5 and quality of life) is associated with significant decreases in IL-5, IL-13, and IL-4 relative to IFN-γ during 2 years of SLIT therapy for HDMs.

Predictors of quality of life improvement in allergic rhinitis patients after sublingual immunotherapy

OBJECTIVES

Sublingual immunotherapy (SLIT) has been described as a significant intervention in the treatment of allergic rhinitis (AR). However, factors that may predict treatment outcomes with respect to quality of life (QoL) results and mainly the role of olfactory function are still being underestimated. In this study, we investigated determinants that best predict treatment outcomes for QoL, exploring mainly the role of olfaction.

METHODS

One hundred forty-five patients following SLIT, 45 placebo-controls, and 48 healthy subjects were studied. Olfactory function was objectively evaluated using "Sniffin' Sticks" test pre- and post-cessation of SLIT. Three categories of validated QoL questionnaires were filled out by all subjects: questionnaire specific for olfaction (Questionnaire of Olfactory Deficits), questionnaires for assessing psychology (Beck Depression Inventory, Zung Depression Scale, State & Trait Anxiety Inventory), general Short Form-36 health survey.

RESULTS

Statistically significant improvement of olfactory function by 11.1% and of all QoL questionnaires results (all P<.001) was observed on final evaluation. Anosmia, asthma history, and the severity of symptoms-expressed by the Total Symptoms Score-were proven independent determinants of clinically significant improvement in patients' QoL.

CONCLUSIONS

Several factors were found that may predict QoL outcomes in AR patients following SLIT.

The evolution of allergen and non-specific immunotherapy: past achievements, current applications and future outlook

Recent epidemiological studies estimated that more than 30% of European suffer from allergic rhinitis or conjunctivitis, while up to 20% suffer from asthma and 15% from allergic skin conditions, while for many other regions the prevalence is increasing. Allergen immunotherapy represents the only available treatment that can modify the allergic disease process, and thus is worth considering as a treatment in affected individuals. A beneficial effect of allergen immunotherapy has been shown in both adults and children affected by allergic rhinitis, allergic conjunctivitis, allergic asthma and hymenoptera venom allergy. The present study represents an overview on allergen immunotherapy, focusing on the principal aspects of the use of immunotherapy in the past, its recent clinical applications and future outlook.

Mechanisms of allergen-specific immunotherapy: multiple suppressor factors at work in immune tolerance to allergens

Allergen-specific immunotherapy (AIT) has been used for more than 100 years as a desensitizing therapy for IgE-mediated allergic diseases and represents a potentially curative way of treatment. The mechanisms of action of AIT include the induction of very early desensitization of mast cells and basophils; generation of regulatory T and regulatory B (Breg) cell responses; regulation of IgE and IgG4; decreases in numbers and activity of eosinophils and mast cells in mucosal allergic tissues; and decreases in the activity of basophils in circulation. Skewing of allergen-specific effector T and effector B cells to a regulatory phenotype appears as a key event in the course of AIT and normal immune response to allergens. Recently, inducible IL-10-secreting Breg cells were also demonstrated to contribute to allergen tolerance through suppression of effector T cells and selective induction of IgG4 isotype antibodies. Allergen-specific regulatory T and Breg cells orchestrate a general immunoregulatory activity, which can be summarized as suppression of cytokines from inflammatory dendritic cells; suppression of effector TH1, TH2, and TH17 cells; suppression of allergen-specific IgE and induction of IgG4; and suppression of migration of mast cells, basophils, eosinophils, and effector T cells to tissues. A detailed knowledge of the mechanisms of AIT is not only important in designing the prevention and treatment of allergic diseases but might also find applications in the treatment of autoimmune diseases, organ transplantation, chronic infection, and cancer.

Sublingual immunotherapy: World Allergy Organization position paper 2013 update

We have prepared this document, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2013 Update", according to the evidence-based criteria, revising and updating chapters of the originally published paper, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2009", available at http://www.waojournal.org. Namely, these comprise: "Mechanisms of sublingual immunotherapy;" "Clinical efficacy of sublingual immunotherapy" - reporting all the data of all controlled trials published after 2009; "Safety of sublingual immunotherapy" - with the recently published Grading System for adverse reactions; "Impact of sublingual immunotherapy on the natural history of respiratory allergy" - with the relevant evidences published since 2009; "Efficacy of SLIT in children" - with detailed analysis of all the studies; "Definition of SLIT patient selection" - reporting the criteria for eligibility to sublingual immunotherapy; "The future of immunotherapy in the community care setting"; "Methodology of clinical trials according to the current scientific and regulatory standards"; and "Guideline development: from evidence-based medicine to patients' views" - including the evolution of the methods to make clinical recommendations.Additionally, we have added new chapters to cover a few emerging crucial topics: "Practical aspects of schedules and dosages and counseling for adherence" - which is crucial in clinical practice for all treatments; "Perspectives and new approaches" - including recombinant allergens, adjuvants, modified allergens, and the concept of validity of the single products. Furthermore, "Raising public awareness about sublingual immunotherapy", as a need for our patients, and strategies to increase awareness of allergen immunotherapy (AIT) among patients, the medical community, all healthcare stakeholders, and public opinion, are also reported in detail.

Allergen-specific immunotherapy for allergic rhinitis in the elderly: is it never too late?

Evaluation of: Bozek A, Ignasiak B, Filipowska B, Jarzab J. House dust mite sublingual immunotherapy: a double-blind, placebo-controlled study in elderly patients with allergic rhinitis. Clin. Exp. Allergy 43(2), 242-248 (2013). There is a well-accepted tenet in allergen-specific immunotherapy (SIT), especially for respiratory allergies such as rhinitis and asthma: this approach should be, in general, reserved for the pediatric population and young adults. This belief is based on the fact that SIT is considered the only therapy able to modify the course of allergic diseases. In the case of allergic rhinitis, for example, SIT could reduce the risk of asthma developing. Therefore, SIT is evaluated with 'the sooner the better' conviction. In elderly people with respiratory allergies, the 'course' of the disease is considered too advanced and therefore the room and therapeutic value of SIT is considered very limited. Bozek et al. evaluated the clinical efficacy of sublingual SIT (SLIT) with house dust mite (HDM) extracts in elderly (age >60 years) patients with a long history of allergic rhinitis due to HDM allergen exposure. In a 3-year double-blind placebo-controlled study, SLIT was able to significantly reduce the nose-related symptoms and the medication score. The conclusions of the authors were that SLIT with HDM allergens resulted in a significant clinical improvement in the active group compared with the placebo group, particularly during the period of the year in which the heating would be on. This therapy was well tolerated. These observations may lead to the more frequent use of SLIT immunotherapy in the elderly.

Trends in Specific Immunotherapy for Allergic Rhinitis: A Survey of Chinese ENT Specialists

Purpose

Specific immunotherapy (SIT) is a suitable but uncommon treatment option for allergic rhinitis (AR) in China. The current understanding and attitude of Chinese ENT (ear, nose, and throat) specialists in regards to SIT is unclear. This study investigates current trends in the awareness and application status of SIT among Chinese ENT specialists.

Methods

We performed a nationwide, cross-sectional survey with a specially designed questionnaire given to 800 ENT specialists in China. A member of the trained research group conducted face-to-face interviews with each respondent.

Results

Most of the respondents considered AR (96.0%) and allergic asthma (96.0%) the most suitable indications for SIT. Of all respondents, 77.0% recommended the application of SIT as early as possible; in addition, SIT was considered 'relatively controllable and safe' by most respondents (80.6%). The highest allergen-positive rate in AR was associated with house dust mite (47.7%) and obvious differences existed among geographical regions. Conventional subcutaneous immunotherapy was the most highly recommended treatment option (96.2%). 'The high cost of SIT' (86.6%) and 'lack of patient knowledge of SIT' (85.2%) were probably the main reasons for the lower clinical use of SIT in China.

Conclusions

Most cases showed that the opinions of Chinese ENT specialists appeared to be in agreement with recent SIT progress and international guidelines; however, many areas still need to enhance the standardization and use of SIT in China. Clinical guidelines for SIT require improvement; in addition, Chinese ENT specialists need continuing medical education on SIT.

Differential CD4+ T-cell responses of allergic and non-allergic subjects to the immunodominant epitope region of the horse major allergen Equ c 1

The responses of allergen-specific CD4(+) T cells of allergic and healthy individuals are still incompletely understood. Our objective was to investigate the functional and phenotypic properties of CD4(+) T cells of horse-allergic and healthy subjects specific to the immunodominant epitope region of the major horse allergen Equ c 1. Specific T-cell lines (TCLs) and clones were generated from peripheral blood mononuclear cells with Equ c 1(143-160), the peptide containing the immunodominant epitope region of Equ c 1. The frequency, proliferative response, cytokine production and HLA restriction of the cells were examined. The frequency of Equ c 1-specific CD4(+) T cells was low (approximately 1 per 10(6) CD4(+) T cells) in both allergic and non-allergic subjects. The cells of allergic subjects had a stronger proliferative capacity than those of non-allergic subjects, and they predominantly emerged from the memory T-cell pool and expressed the T helper type 2 cytokine profile, whereas the cells of non-allergic subjects emerged from the naive T-cell pool and produced low levels of interferon-γ and interleukin-10. T-cell response to Equ c 1(143-160) was restricted by several common HLA class II molecules from both DQ and DR loci. As the phenotypic and functional properties of Equ c 1-specific CD4(+) T cells differ between allergic and non-allergic subjects, allergen-specific T cells appear to be tightly implicated in the development of diseased or healthy outcome. Restriction of the specific CD4(+) T-cell response by multiple HLA alleles suggests that Equ c 1(143-160) is a promising candidate for peptide-based immunotherapy.

Aluminium adjuvants and adverse events in sub-cutaneous allergy immunotherapy

Sub-cutaneous immunotherapy is an effective treatment for allergy. It works by helping to modify or re-balance an individual’s immune response to allergens and its efficacy is greatly improved by the use of adjuvants, most commonly, aluminium hydroxide. Aluminium salts have been used in allergy therapy for many decades and are assumed to be safe with few established side-effects. This assumption belies their potency as adjuvants and their potential for biological reactivity both at injection sites and elsewhere in the body. There are very few data purporting to the safety of aluminium adjuvants in allergy immunotherapy and particularly so in relation to longer term health effects. There are, if only few, published reports of adverse events following allergy immunotherapy and aluminium adjuvants are the prime suspects in the majority of such incidents. Aluminium adjuvants are clearly capable of initiating unwanted side effects in recipients of immunotherapy and while there is as yet no evidence that such are commonplace it is complacent to consider aluminium salts as harmless constituents of allergy therapies. Future research should establish the safety of the use of aluminium adjuvants in sub-cutaneous allergy immunotherapy.

Guideline on allergen-specific immunotherapy in IgE-mediated allergic diseases: S2k Guideline of the German Society for Allergology and Clinical Immunology (DGAKI), the Society for Pediatric Allergy and Environmental Medicine (GPA), the Medical Association of German Allergologists (AeDA), the Austrian Society for Allergy and Immunology (ÖGAI), the Swiss Society for Allergy and Immunology (SGAI), the German Society of Dermatology (DDG), the German Society of Oto- Rhino-Laryngology, Head and Neck Surgery (DGHNO-KHC), the German Society of Pediatrics and Adolescent Medicine (DGKJ), the Society for Pediatric Pneumology (GPP), the German Respiratory Society (DGP), the German Association of ENT Surgeons (BV-HNO), the Professional Federation of Paediatricians and Youth Doctors (BVKJ), the Federal Association of Pulmonologists (BDP) and the German Dermatologists Association (BVDD)

The present guideline (S2k) on allergen-specific immunotherapy (AIT) was established by the German, Austrian and Swiss professional associations for allergy in consensus with the scientific specialist societies and professional associations in the fields of otolaryngology, dermatology and venereology, pediatric and adolescent medicine, pneumology as well as a German patient organization (German Allergy and Asthma Association; Deutscher Allergie- und Asthmabund, DAAB) according to the criteria of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF). AIT is a therapy with disease-modifying effects. By administering allergen extracts, specific blocking antibodies, toler-ance-inducing cells and mediators are activated. These prevent further exacerbation of the allergen-triggered immune response, block the specific immune response and attenuate the inflammatory response in tissue. Products for SCIT or SLIT cannot be compared at present due to their heterogeneous composition, nor can allergen concentrations given by different manufacturers be compared meaningfully due to the varying methods used to measure their active ingredients. Non-modified allergens are used for SCIT in the form of aqueous or physically adsorbed (depot) extracts, as well as chemically modified allergens (allergoids) as depot extracts. Allergen extracts for SLIT are used in the form of aqueous solutions or tablets. The clinical efficacy of AIT is measured using various scores as primary and secondary study endpoints. The EMA stipulates combined symptom and medication scores as primary endpoint. A harmonization of clinical endpoints, e. g., by using the combined symptom and medication scores (CSMS) recommended by the EAACI, is desirable in the future in order to permit the comparison of results from different studies. The current CONSORT recommendations from the ARIA/GA2LEN group specify standards for the evaluation, presentation and publication of study results. According to the Therapy allergen ordinance (TAV), preparations containing common allergen sources (pollen from grasses, birch, alder, hazel, house dust mites, as well as bee and wasp venom) need a marketing authorization in Germany. During the marketing authorization process, these preparations are examined regarding quality, safety and efficacy. In the opinion of the authors, authorized allergen preparations with documented efficacy and safety, or preparations tradeable under the TAV for which efficacy and safety have already been documented in clinical trials meeting WAO or EMA standards, should be preferentially used. Individual formulations (NPP) enable the prescription of rare allergen sources (e.g., pollen from ash, mugwort or ambrosia, mold Alternaria, animal allergens) for specific immunotherapy. Mixing these allergens with TAV allergens is not permitted. Allergic rhinitis and its associated co-morbidities (e. g., bronchial asthma) generate substantial direct and indirect costs. Treatment options, in particular AIT, are therefore evaluated using cost-benefit and cost-effectiveness analyses. From a long-term perspective, AIT is considered to be significantly more cost effective in allergic rhinitis and allergic asthma than pharmacotherapy, but is heavily dependent on patient compliance. Meta-analyses provide unequivocal evidence of the efficacy of SCIT and SLIT for certain allergen sources and age groups. Data from controlled studies differ in terms of scope, quality and dosing regimens and require product-specific evaluation. Therefore, evaluating individual preparations according to clearly defined criteria is recommended. A broad transfer of the efficacy of certain preparations to all preparations administered in the same way is not endorsed. The website of the German Society for Allergology and Clinical Immunology (www.dgaki.de/leitlinien/s2k-leitlinie-sit; DGAKI: Deutsche Gesellschaft für Allergologie und klinische Immunologie) provides tables with specific information on available products for AIT in Germany, Switzerland and Austria. The tables contain the number of clinical studies per product in adults and children, the year of market authorization, underlying scoring systems, number of randomized and analyzed subjects and the method of evaluation (ITT, FAS, PP), separately given for grass pollen, birch pollen and house dust mite allergens, and the status of approval for the conduct of clinical studies with these products. Strong evidence of the efficacy of SCIT in pollen allergy-induced allergic rhinoconjunctivitis in adulthood is well-documented in numerous trials and, in childhood and adolescence, in a few trials. Efficacy in house dust mite allergy is documented by a number of controlled trials in adults and few controlled trials in children. Only a few controlled trials, independent of age, are available for mold allergy (in particular Alternaria). With regard to animal dander allergies (primarily to cat allergens), only small studies, some with methodological deficiencies are available. Only a moderate and inconsistent therapeutic effect in atopic dermatitis has been observed in the quite heterogeneous studies conducted to date. SCIT has been well investigated for individual preparations in controlled bronchial asthma as defined by the Global Initiative for Asthma (GINA) 2007 and intermittent and mild persistent asthma (GINA 2005) and it is recommended as a treatment option, in addition to allergen avoidance and pharmacotherapy, provided there is a clear causal link between respiratory symptoms and the relevant allergen. The efficacy of SLIT in grass pollen-induced allergic rhinoconjunctivitis is extensively documented in adults and children, whilst its efficacy in tree pollen allergy has only been shown in adults. New controlled trials (some with high patient numbers) on house dust mite allergy provide evidence of efficacy of SLIT in adults. Compared with allergic rhinoconjunctivitis, there are only few studies on the efficacy of SLIT in allergic asthma. In this context, newer studies show an efficacy for SLIT on asthma symptoms in the subgroup of grass pollen allergic children, adolescents and adults with asthma and efficacy in primary house dust mite allergy-induced asthma in adolescents aged from 14 years and in adults. Aspects of secondary prevention, in particular the reduction of new sensitizations and reduced asthma risk, are important rationales for choosing to initiate treatment early in childhood and adolescence. In this context, those products for which the appropriate effects have been demonstrated should be considered. SCIT or SLIT with pollen or mite allergens can be performed in patients with allergic rhinoconjunctivitis using allergen extracts that have been proven to be effective in at least one double-blind placebo-controlled (DBPC) study. At present, clinical trials are underway for the indication in asthma due to house dust mite allergy, some of the results of which have already been published, whilst others are still awaited (see the DGAKI table "Approved/potentially completed studies" via www.dgaki.de/Leitlinien/s2k-Leitlinie-sit (according to www.clinicaltrialsregister.eu)). When establishing the indication for AIT, factors that favour clinical efficacy should be taken into consideration. Differences between SCIT and SLIT are to be considered primarily in terms of contraindications. In individual cases, AIT may be justifiably indicated despite the presence of contraindications. SCIT injections and the initiation of SLIT are performed by a physician experienced in this type of treatment and who is able to administer emergency treatment in the case of an allergic reaction. Patients must be fully informed about the procedure and risks of possible adverse events, and the details of this process must be documented (see "Treatment information sheet"; available as a handout via www.dgaki.de/Leitlinien/s2k-Leitlinie-sit). Treatment should be performed according to the manufacturer's product information leaflet. In cases where AIT is to be performed or continued by a different physician to the one who established the indication, close cooperation is required in order to ensure that treatment is implemented consistently and at low risk. In general, it is recommended that SCIT and SLIT should only be performed using preparations for which adequate proof of efficacy is available from clinical trials. Treatment adherence among AIT patients is lower than assumed by physicians, irrespective of the form of administration. Clearly, adherence is of vital importance for treatment success. Improving AIT adherence is one of the most important future goals, in order to ensure efficacy of the therapy. Severe, potentially life-threatening systemic reactions during SCIT are possible, but - providing all safety measures are adhered to - these events are very rare. Most adverse events are mild to moderate and can be treated well. Dose-dependent adverse local reactions occur frequently in the mouth and throat in SLIT. Systemic reactions have been described in SLIT, but are seen far less often than with SCIT. In terms of anaphylaxis and other severe systemic reactions, SLIT has a better safety profile than SCIT. The risk and effects of adverse systemic reactions in the setting of AIT can be effectively reduced by training of personnel, adhering to safety standards and prompt use of emergency measures, including early administration of i. m. epinephrine. Details on the acute management of anaphylactic reactions can be found in the current S2 guideline on anaphylaxis issued by the AWMF (S2-AWMF-LL Registry Number 061-025). AIT is undergoing some innovative developments in many areas (e. g., allergen characterization, new administration routes, adjuvants, faster and safer dose escalation protocols), some of which are already being investigated in clinical trials. Cite this as Pfaar O, Bachert C, Bufe A, Buhl R, Ebner C, Eng P, Friedrichs F, Fuchs T, Hamelmann E, Hartwig-Bade D, Hering T, Huttegger I, Jung K, Klimek L, Kopp MV, Merk H, Rabe U, Saloga J, Schmid-Grendelmeier P, Schuster A, Schwerk N, Sitter H, Umpfenbach U, Wedi B, Wöhrl S, Worm M, Kleine-Tebbe J. Guideline on allergen-specific immunotherapy in IgE-mediated allergic diseases - S2k Guideline of the German Society for Allergology and Clinical Immunology (DGAKI), the Society for Pediatric Allergy and Environmental Medicine (GPA), the Medical Association of German Allergologists (AeDA), the Austrian Society for Allergy and Immunology (ÖGAI), the Swiss Society for Allergy and Immunology (SGAI), the German Society of Dermatology (DDG), the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNO-KHC), the German Society of Pediatrics and Adolescent Medicine (DGKJ), the Society for Pediatric Pneumology (GPP), the German Respiratory Society (DGP), the German Association of ENT Surgeons (BV-HNO), the Professional Federation of Paediatricians and Youth Doctors (BVKJ), the Federal Association of Pulmonologists (BDP) and the German Dermatologists Association (BVDD). Allergo J Int 2014;23:282-319.

Pediatric allergic rhinitis and asthma: can the march be halted?

The strong epidemiologic and pathophysiologic link between allergic rhinitis (AR) and asthma has led to the concept of 'united airways disease' or 'respiratory allergy', implying that allergy, in its widest sense, underlies this clinical syndrome. Progression from AR to asthma is frequent and part of the 'atopic march'. Since pediatric immune responses are more adaptable and therefore may be more amenable to treatment, interventions at early childhood are characterized by a higher chance to affect the natural history of respiratory allergy. Although current treatments are quite effective in alleviating respiratory allergy symptoms, it has proven much more difficult to confirm any influence on the progression of the disease. Much more promising is the field of specific allergen immunotherapy, where current evidence, although not yet of ideal robustness, points towards a disease-modifying effect. In addition, newer or emerging, possibly more effective or more targeted interventions are promising in the preventive sense.

A comparison of immunotherapy delivery methods for allergen immunotherapy

BACKGROUND

Allergic diseases are among the most common diseases in humans. Besides allergen avoidance, allergen-specific immunotherapy is the only causative treatment option. During recent years, many innovations of this therapy have emerged.

METHODS

Selective literature research in Medline and PubMed, under the inclusion of national and international guidelines and Cochrane meta analyses.

RESULTS

In several meta-analyses, the clinical efficacy of subcutaneous immunotherapy (SCIT) has been largely demonstrated. Recently, major research activities in mucosal immunotherapies focused on the sublingual application route. There are well-documented clinical data on the efficacy and safety of this form of immunotherapy. New application routes as well as new immune-modifying agents such as virus-like particles or CpG-motifs have also been investigated.

CONCLUSION

SIT is accepted to be the only causative treatment option for allergies. New application routes and new immune-modifying agents will allow for different delivery methods in the future.

Peptide-induced immune regulation by a promiscuous and immunodominant CD4T-cell epitope of Timothy grass pollen: a role of Cbl-b and Itch in regulation

BACKGROUND

T-cell targeted peptide epitope tolerogens from grass pollen allergens may be useful in treating seasonal allergic rhinitis, but there is urgent need for optimisation of approaches from improved understanding of mechanism.

OBJECTIVE

We sought to identify human leukocyte antigen (HLA)-DR1-restricted epitopes from the Timothy grass pollen allergen, Phleum pratense, and characterise T-cell immune regulation following intranasal administration of a single, immunodominant epitope.

METHODS

T-cell epitopes within P pratense were identified using HLA-DR1 transgenic mice and tetramer-guided epitope mapping (TGEM) in HLA-DR1-positive individuals with grass allergy. An immunodominant epitope was tested in HLA-DR1 transgenics for impact on responses to whole Phl p5 b or peptide. Microarrays and quantitative PCR were used to characterise T-cell immunity.

RESULTS

Peptide 26 (p26) was identified in HLA-DR1 transgenic mice and by TGEM analysis of HLA-DR1-positive individuals with grass allergy. p26 shows promiscuous binding to a wide range of HLA class II alleles, making it of relevance across immunogenetically diverse patients. The epitope is conserved in rye and velvet grass, making it applicable across a spectrum of grass pollen allergy. Intranasal pretreatment of mice with p26 results in significantly reduced T-cell responses. Transcriptomic array analysis in mice showed T-cell regulation in the intranasal treatment group associated with increased expression of members of the Cbl-b and Itch E3 ubiquitin ligase pathway.

CONCLUSIONS

We defined an immunodominant P pratense epitope, p26, with broad binding across multiple HLA class II alleles. Intranasal treatment of mice with p26 results in T-cell regulation to whole allergen, involving the Cbl-b and Itch regulatory pathway.

Balancing efficacy against safety in sublingual immunotherapy with inhalant allergens: what is the best approach?

Over the last 20 years, studies and clinical trials have demonstrated efficacy, safety and cost-effectiveness of sublingual immunotherapy (SLIT) for respiratory allergic diseases. Nevertheless, it seems to be mostly used as a second-line therapeutic option, and adherence to treatment is not always optimal. Selective literature research was done in Medline and PubMed, including guidelines, position papers and Cochrane meta-analyses concerning SLIT in adult patients. The most recent reviews confirm SLIT as viable and efficacious treatment especially for allergic rhinitis, even if the optimal dosage, duration, schedule are not clearly established for most of the products. Despite an optimal safety profile, tolerability and patient-reported outcomes concerning SLIT have received poor attention until now. Recently, new tools have been specifically developed in order to investigate these aspects. Regular assessment of tolerability profile and SLIT-related patient-reported outcomes will allow balancing efficacy with tolerability and all the other patient-related variables that may affect treatment effectiveness beyond its efficacy.

Allergy training and immunotherapy in Latin America: results of a regional overview

BACKGROUND

One main practice gap in allergology that has been detected in several regions of the world is the application of specific immunotherapy (SIT). The prescription and practice of SIT should characterize allergologic specialists, but there are regional discrepancies in such practice. A detailed knowledge of the regulatory and legislation aspects and drawbacks would help improve and harmonize SIT practice.

OBJECTIVE

To describe in Latin America the level of allergy training and the characteristics of the use of SIT, including the medical and legal aspects.

METHODS

Three sources were used: a 24-item questionnaire sent to 22 allergologic leaders in 11 Latin American countries, 2 face-to-face meetings, and information from health authorities involved in the approval of medical substances.

RESULTS

In 56% of countries, the specialty of allergology is a third-level care specialty and/or a subspecialty. Two countries have a special training program for pediatric allergists. Passing a board examination is mandatory in 3 countries, and recertification every 2 to 5 years occurs without examination. Sublingual and subcutaneous SITs are available in all Latin American countries. No legislation restricts SIT prescription and it can be performed by nonspecialists in 7 of 11 countries. In 90% of countries, allergists use allergen extracts from the United States (subcutaneous immunotherapy) and Europe (sublingual and subcutaneous immunotherapies), and 50% also manufacture extracts locally. Only 1 country has legal requirements for the quality of raw materials.

CONCLUSION

The present analysis helps to identify gaps in the field of allergologic training and SIT in Latin America, many of them amendable.

Paediatric rhinitis: position paper of the European Academy of Allergy and Clinical Immunology

Rhinitis is a common problem in childhood and adolescence and impacts negatively on physical, social and psychological well-being. This position paper, prepared by the European Academy of Allergy and Clinical Immunology Taskforce on Rhinitis in Children, aims to provide evidence-based recommendations for the diagnosis and therapy of paediatric rhinitis. Rhinitis is characterized by at least two nasal symptoms: rhinorrhoea, blockage, sneezing or itching. It is classified as allergic rhinitis, infectious rhinitis and nonallergic, noninfectious rhinitis. Similar symptoms may occur with other conditions such as adenoidal hypertrophy, septal deviation and nasal polyps. Examination by anterior rhinoscopy and allergy tests may help to substantiate a diagnosis of allergic rhinitis. Avoidance of relevant allergens may be helpful for allergic rhinitis (AR). Oral and intranasal antihistamines and nasal corticosteroids are both appropriate for first-line AR treatment although the latter are more effective. Once-daily forms of corticosteroids are preferred given their improved safety profile. Potentially useful add-on therapies for AR include oral leukotriene receptor antagonists, short bursts of a nasal decongestant, saline douches and nasal anticholinergics. Allergen-specific immunotherapy is helpful in IgE-mediated AR and may prevent the progression of allergic disease. There are still a number of areas that need to be clarified in the management of rhinitis in children and adolescents.

Protocol for a double-blind randomised controlled trial of low dose intradermal grass pollen immunotherapy versus a histamine control on symptoms and medication use in adults with seasonal allergic rhinitis (PollenLITE)

BACKGROUND

Subcutaneous immunotherapy with high dose grass pollen (typically microgram quantities) was first described over 100 years ago. This treatment suppresses allergen-induced cutaneous late responses, with lesser effects on early responses. We previously reported that repeated 2-weekly intradermal injections of grass pollen - containing approximately 7 ng of major allergen Phl p 5 - led to a progressive suppression of the allergen-induced cutaneous response, and that by the sixth injection, this was inhibited by over 90%. The purpose of this trial is to investigate the clinical efficacy of intradermal desensitisation with low doses (i.e. nanogram quantities) of grass pollen allergen for seasonal allergic rhinitis.

METHODS/DESIGN

The Pollen Low dose Intradermal therapy Evaluation (PollenLITE) is a single centre double-blind randomised parallel group controlled trial of the efficacy and safety of intradermal grass pollen injections plus standard treatment, versus histamine injections plus standard treatment, in adults with moderate-severe grass pollen-induced allergic rhinitis ('summer hay fever'). A minimum of ninety adults with a history of moderate-severe persistent allergic rhinitis during the UK grass pollen season will be randomised into two equal groups to receive 7 or 8 intradermal injections of grass pollen extract (containing approximately 7 ng of major allergen Phl p 5) or histamine, before the grass pollen season. In the summer, participants will score their symptoms, medication requirements, visual analogue scores, and complete EuroQOL (EQ-5D-5 L) and mini Rhinoconjunctivitis Quality of Life Questionnaires. Global assessments will also be recorded at the end of the pollen season. Blood samples will be collected from all participants for mechanistic immune assays. Skin punch biopsies will also be collected in 40 participants selected at random from intradermal injection sites after the grass pollen season for mechanistic assays. Finally, to investigate if the desensitising effect of intradermal immunotherapy on cutaneous responses is long-lasting, all participants will be randomised to receive a follow up intradermal injection after 3, 6 or 12 months with measurement of early and late response sizes.

DISCUSSION

Randomisation began in February 2013 and the final participant will complete the trial protocol in August 2014.

TRIAL REGISTRATION

ISRCTN 78413121EudraCT number 2012-002193-31.

Sublingual immunotherapy in children with allergic rhinoconjunctivitis mono-sensitized to house-dust-mites: a double-blind-placebo-controlled randomised trial

BACKGROUND

Although sublingual immunotherapy (SLIT) has been demonstrated to be a safe and efficient treatment in children with seasonal allergic rhinitis (AR), there is little evidence on the efficacy of SLIT with house-dust-mite (HDM) extract in children with isolated perennial AR.

OBJECTIVES

We sought to assess the clinical efficacy and safety of HDM-SLIT in children with isolated allergic rhinitis-conjunctivitis mono-sensitized to HDM without asthma symptoms.

METHODS

Twenty-two children (aged 5-10 years) with perennial AR and conjunctivitis symptoms mono-sensitized to Dermatophagoides pteronyssinus and Dermatophagoides farinae were enrolled. During a 2 months run-in period, symptom and medication scores, lung functions, bronchial hyperreactivity, nasal provocation and skin prick tests were evaluated. Subjects were randomized to active or placebo using a double-blind method. A total of eighteen subjects were randomised to receive either active SLIT or placebo for 12 months. Daily symptom and medication scores, baseline lung functions, bronchial hyperreactivity, nasal provocation and skin prick tests were recorded and re-evaluated at the end of treatment.

RESULTS

After one year of treatment, no significant differences were detected in the between groups and within group comparisons based on total rhinitis symptom/medication scores (p > 0.05). Skin reactivity to Dermatophagoides pteronyssinus was significantly reduced in HDM-SLIT compared to placebo group (p = 0.018). A significant reduction in nasal sensitivity was observed in SLIT group after one year treatment when compared to baseline (p = 0.04). Total conjunctivitis symptoms were reduced significantly in both active and lacebo group at the end of treatment compared to baseline. The proportion of patients with non-specific bronchial hyperreactivity increased to almost 3-fold in placebo group compared to baseline.

CONCLUSION

HDM-SLIT was not superior to placebo in reducing isolated rhinoconjunctivitis symptoms within 12 months of treatment. However, HDM-SLIT has a modulating effect on allergen-specific nasal and skin reactivity in isolated perennial AR children.

CLINICAL TRIAL REGISTRATION

The trial was registered at Anzctr.org.au number, ACTRN12613000315718.

Novel birch pollen specific immunotherapy formulation based on contiguous overlapping peptides

Background

Synthetic contiguous overlapping peptides (COPs) may represent an alternative to allergen extracts or recombinant allergens for allergen specific immunotherapy. In combination, COPs encompass the entire allergen sequence, providing all potential T cell epitopes, while preventing IgE conformational epitopes of the native allergen.

Methods

Individual COPs were derived from the sequence of Bet v 1, the major allergen of birch pollen, and its known crystal structure, and designed to avoid IgE binding. Three sets of COPs were tested in vitro in competition ELISA and basophil degranulation assays. Their in vivo reactivity was determined by intraperitoneal challenge in rBet v 1 sensitized mice as well as by skin prick tests in volunteers with allergic rhinoconjunctivitis to birch pollen.

Results

The combination, named AllerT, of three COPs selected for undetectable IgE binding in competition assays and for the absence of basophil activation in vitro was unable to induce anaphylaxis in sensitized mice in contrast to rBet v 1. In addition no positive reactivity to AllerT was observed in skin prick tests in human volunteers allergic to birch pollen. In contrast, a second set of COPs, AllerT4-T5 displayed some residual IgE binding in competition ELISA and a weak subliminal reactivity to skin prick testing.

Conclusions

The hypoallergenicity of contiguous overlapping peptides was confirmed by low, if any, IgE binding activity in vitro, by the absence of basophil activation and the absence of in vivo induction of allergic reactions in mouse and human.

Trial registration

ClinicalTrials.gov NCT01719133

Developments in the field of allergy in 2011 through the eyes of Clinical and Experimental Allergy

As in previous years, we felt it would be of value to our readership to summarize the new information provided by the authors who have published in Clinical and Experimental Allergy in 2011 and set this in the context of recent advances in our understanding of the pathogenesis and management of allergic disease in all its many manifestations. In 2011, about 210 articles were published in Clinical and Experimental Allergy including editorials, reviews, opinion articles, guidelines, letters, book reviews and of course at the heart of the journal, papers containing original data. As before, this review is divided into sections based on the way the journal is structured, although this year we have grouped together all the papers dealing with mechanisms of allergic disease, whether they involve patients (clinical mechanisms), pure in vitro studies (basic mechanisms) or animal models (experimental models), as we felt this was a more coherent way to deal with the subject. In the field of asthma and rhinitis, the relationship between airway inflammation and airway dysfunction was of perennial interest to investigators, as were phenotypes and biomarkers. Aspirin hypersensitivity appeared in studies in several papers and there was new interest in asthma in the elderly. The mechanisms involved in allergic disease describe advances in our understanding of T cell responses, the relationship between inflammation and disease, mast cell and basophil activation, steroid resistance and novel therapies. In the section dealing with epidemiology, studies seeking to identify risk factors for allergic disease including vitamin D are prominent, as once again are studies investigating gene-environment interactions. The clinical allergy section focuses on drug allergy, food allergy and immunotherapy. The area of oral immunotherapy for food allergy is well covered and we were grateful to Stephen Durham for guest editing an outstanding special issue on immunotherapy in the centenary year of Leonard Noon's pioneering work. Lastly, in the field of allergens, the interest in component-resolved diagnosis continues to grow and there are also articles describing important novel cultivars and the effect of food processing on the allergenic properties of foods. Another terrific year, full of important and high-quality work,which the journal has been proud to bring to the allergy community.

Current and future directions in pediatric allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is a common pediatric problem that significantly affects sleep, learning, performance, and quality of life. In addition, it is associated with significant comorbidities and complications.

OBJECTIVE

The aim was to provide an update on the epidemiology, comorbidities, pathophysiology, current treatment, and future direction of pediatric AR.

METHODS

Literature reviews in each of these areas were conducted, and the results were incorporated.

RESULTS

The prevalence of AR is increasing in the pediatric population and is associated with significant morbidity, comorbidities, and complications. The mainstay of current treatment strategies includes allergen avoidance, pharmacotherapy, and allergen specific immunotherapy.

CONCLUSIONS

In the future, diagnosis will be improved by microarrayed recombinant allergen testing and therapy will be expanded to include emerging treatments such as sublingual immunotherapy and combination products.

Subcutaneous and sublingual immunotherapy for seasonal allergic rhinitis: a systematic review and indirect comparison

BACKGROUND

Severe allergic rhinitis uncontrolled by pharmacotherapy can adversely affect quality of life. Both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) have demonstrated effectiveness in this patient group; however, it remains uncertain which route of administration is more effective.

OBJECTIVES

We sought to update existing systematic reviews on the clinical effectiveness of SCIT and SLIT versus placebo, to undertake a systematic review of head-to-head trials, and to compare the relative effectiveness of SCIT and SLIT in an adjusted indirect comparison.

METHODS

Standard systematic review methods aimed at minimizing bias were used. Double-blind, randomized, placebo-controlled trials of SCIT or SLIT or trials of SCIT versus SLIT were included. Meta-analysis and indirect comparison meta-analysis with meta-regression were performed.

RESULTS

Updated meta-analyses confirmed statistically significant benefits for SCIT and SLIT compared with placebo in adults and, to a lesser extent, in children. Only 1 head-to-head trial met the inclusion criteria; both this and the indirect comparisons did not provide conclusive results in favor of either SCIT or SLIT based on symptom-medication or quality-of-life scores. There was a trend toward favoring SCIT for symptom and medication scores.

CONCLUSIONS

Although there is clear evidence of effectiveness of both SCIT and SLIT, superiority of one mode of administration over the other could not be consistently demonstrated through indirect comparison, and further research is needed to establish the comparative effectiveness of SCIT versus SLIT.

Specific immunotherapy-indications and mode of action

BACKGROUND

It is estimated that up to 24% of the population in Germany suffers from allergic rhinoconjunctivitis and 5% from allergic asthma. Allergic rhinoconjunctivitis is closely related to other atopic diseases.

METHODS

This review is based on pertinent publications retrieved by a selective search of the Medline database, guidelines from Germany and abroad, and Cochrane meta-analyses.

RESULTS

Specific immunotherapy (SIT) is the only diseases-modifying treatment option for allergies. Meta-analysis reveals standardized mean differences in allergic rhinitis symptom scores of -0.73 for subcutaneous immunotherapy (SCIT) and -0.49 for sublingual immunotherapy (SLIT); the corresponding mean differences in medication scores are -0.57 and -0.32, respectively. The treatment should be carried out for at least three years. It is indicated when the symptoms are severe and allergen avoidance is not a realistic option. The efficacy of treatment depends on the allergen dose; thus, every allergen preparation should be evaluated individually, independent of route of administration. SCIT can cause systemic adverse effects, including anaphylaxis. SLIT is safer but often causes allergic symptoms of the oral mucosa at the beginning of treatment.

CONCLUSION

Even though the efficacy of SIT is well documented, it is still underused. SIT should be offered as standard treatment to patients suffering from allergic rhinitis.