A randomized placebo-controlled trial of rush preseasonal depigmented polymerized grass pollen immunotherapy

Breaking the mold: nontraditional approaches to allergen immunotherapy for environmental allergens

Allergen immunotherapy is a disease-modifying treatment for allergic diseases. The predominant traditional immunotherapy is through subcutaneous administration of allergens to gradually desensitize allergic individuals. While effective, traditional allergen immunotherapy approaches are often lengthy, time consuming for patients and can result in local or systemic adverse reactions. Nontraditional immunotherapies are emerging as promising alternatives, offering potentially more convenient, safe and efficacious treatment options. This review sought to comprehensively examine the safety, efficacy and performance of various nontraditional immunotherapies for environmental allergens. Nontraditional immunotherapy approaches covered in this review include sublingual, local nasal, intralymphatic rush and ultra-rush immunotherapy, allergoid, microbial and anti-IgE immunotherapies. Nontraditional immunotherapies show significant promise in addressing the limitations of traditional subcutaneous immunotherapy. Methods like intralymphatic and rush immunotherapy offer shorter treatment regimens, enhancing patient adherence and convenience. The co-administration of probiotics or monoclonal antibodies, like omalizumab, with AIT appears to improve treatment efficacy and safety. Despite these advancements, further large-scale, long-term studies are needed to establish standardized protocols, dosing and validate long-term effects of these nontraditional immunotherapies. Standardizing outcome measurements across studies is crucial for accurate comparisons of nontraditional immunotherapies prior to widespread clinical adoption of these innovative techniques.

[Allergen-specific immunotherapy : A brief overview in association with allergic conjunctivitis]

Allergen-specific immunotherapy (AIT) is the only causal and disease-modifying treatment for immunoglobulin E (IgE)-mediated type I allergies. Regular exposure to the causative allergen results in an immunomodulatory effect by which the predominant T‑helper (Th) 2 lymphocyte response is shifted to a Th1 lymphocyte response and more allergen-specific blocking immunoglobulins are produced. The approval of substances for AIT is regulated by the Therapy Allergens Ordinance (TAV). There are subcutaneous and/or sublingual AITs for the following indications: allergic rhinitis, allergic conjunctivitis, allergic asthma and insect venom allergy. In this article the indications for allergic conjunctivitis are discussed in particular. Clinical symptoms and a relevant type 1 sensitization are the prerequisites for the indications for AIT. The assessment of the indications and carrying out an AIT should only be carried out by physicians who have been trained in allergology.

Single-cell RNA sequencing identifies precise tolerogenic cellular and molecular pathways induced by depigmented-polymerized grass pollen allergen extract

BACKGROUND

Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these immunotherapeutic vaccine products. Novel single-cell RNA sequencing technology offers a bridge to this gap in knowledge.

OBJECTIVE

We sought to identify the underpinning tolerogenic molecular and cellular mechanisms of depigmented-polymerized Phleum pratense (Phl p) extract.

METHODS

The molecular mechanisms underlying native Phl p, depigmented Phl p (DPG-Phl p), and depigmented-polymerized (DPG-POL-Phl p) allergoid were investigated by single-cell RNA sequencing. Allergen-specific T_H2A, T follicular helper (Tfh), and IL-10⁺ regulatory B cells were quantified by flow cytometry in peripheral blood mononuclear cells from 16 grass pollen-allergic and 8 nonatopic control subjects. The ability of Phl p, DPG-Phl p, and DPG-POL-Phl p to elicit FcεRI- and FcεRII-mediated IgE responses was measured by basophil activation test and IgE-facilitated allergen binding assay.

RESULTS

Analysis revealed that DPG-POL-Phl p downregulated genes associated with T_H2 signaling, induced functional regulatory T cells exhibiting immunosuppressive roles through CD52 and Siglec-10, modulated genes encoding immunoproteasome that dysregulate the processing and presentation of antigens to T cells and promoted a shift from IgE toward an IgA₁ and IgG responses. In grass pollen-allergic subjects, DPG-POL-Phl p exhibited reduced capacity to elicit proliferation of T_H2A, IL-4⁺ Tfh and IL-21⁺ Tfh cells while being the most prominent at inducing IL-10⁺CD19⁺CD5^hi and IL-10⁺CD19⁺CD5^hiCD38^intCD24^int regulatory B-cell subsets compared to Phl p (all P < .05). Furthermore, DPG-POL-Phl p demonstrated a hypoallergenic profile through basophil activation and histamine release compared to Phl p (31.54-fold, P < .001).

CONCLUSIONS

Single-cell RNA sequencing provides an in-depth resolution of the mechanisms underlying the tolerogenic profile of DPG-POL-Phl p.

A real-world retrospective study of safety, efficacy, compliance and cost of combination treatment with rush immunotherapy plus one dose of pretreatment anti-IgE in Chinese children with respiratory allergies

Background

The efficacy of allergen immunotherapy (AIT) in treating pediatric allergy has been clearly demonstrated, however, many patients hesitate to initiate AIT due to weekly hospital visits during the 3-4 months up-dosing phase. Meanwhile, rush immunotherapy (RIT) shortens the duration of the up-dosing phase to 7 days. However, considering that patients receiving RIT are exposed to the allergens during a much shorter period of time and thus may be at a greater risk of systemic reactions, RIT is currently underused, especially in children. This study investigated the utility of combination treatment with RIT plus 1 dose of pretreatment anti-IgE in children with respiratory allergies.

Methods

In this retrospective study, we reviewed records of children with allergic rhinitis (AR) and/or allergic asthma (AA) sensitized to dust mite allergens receiving RIT+1 dose of pretreatment anti-IgE (the RIT group) or conventional immunotherapy (the CIT group) at our hospital from January 2020 to March 2021. Data such as visual analogue scale (VAS) scores, comprehensive symptom and medication score (CSMS), allergy blood test results, adverse reactions, compliance and cost were collected and analyzed.

Results

40 patients in the RIT group and 81 patients in the CIT group were included in this study. Both treatments were well tolerated and patients in the 2 treatment groups had comparable local and systemic reactions. Compared to CIT, RIT + anti-IgE combination led to significantly faster symptomatic improvement as demonstrated by significantly decreased VAS and CSMS starting as early as 1 month after AIT initiation (P&lt;0.05). Nobody dropped out in the RIT group during the 1 year follow-up, while 11 out of 81 patients in the CIT group dropped out (loss rate 13.5%). Thus, the RIT group had a significantly higher compliance rate than the CIT group (P&lt;0.05). Finally, the 2 treatment regimens had comparable cost per patient per injection (P&gt; 0.05).

Conclusions

RIT + 1 dose of pretreatment anti-IgE combination has practical advantages over CIT, including comparable safety, better compliance, and probably a faster onset of clinical efficacy at no additional cost, so it can be an useful regimen for the treatment of Chinese children with respiratory allergies.

The Role of Allergen-Specific Immunotherapy in ENT Diseases: A Systematic Review

Previous studies have demonstrated that both subcutaneous (SCIT) and sublingual specific immunotherapy (SLIT) are effective in treating allergic rhinitis (AR). Further studies have evaluated the efficacy of allergen-specific immunotherapy (AIT) on different ear, nose, and throat (ENT) manifestations, in which allergy might have an etiopathogenetic role, such as local allergic rhinitis (LAR), rhinosinusitis (RS), otitis media (OM), and adenotonsillar (AT) disease. Nevertheless, the management of allergy in ENT diseases is still debated. To the best of our knowledge, this is the first systematic review assessing the efficacy of AIT in ENT diseases aside from AR. Literature data confirmed that AIT might be an effective therapeutic option in LAR, although its effect is restricted to studies with short-term follow-up. Furthermore, previous research demonstrated that AIT may improve symptoms and surgical outcomes of chronic rhinosinusitis when used as an adjunctive treatment. Few studies supported the hypothesis that AIT may exert positive therapeutic effects on recurrent upper airway infections as adenotonsillar disease. Finally, some clinical observations suggested that AIT may add some benefits in the management of otitis media with effusion (OME). The results of this systematic review allow us to conclude that the efficacy of AIT in ENT disorders has been only slightly investigated and additional studies are needed.

miRNA profiles change during grass pollen immunotherapy irrespective of clinical outcome

Background: Subcutaneous immunotherapy (SCIT) is widely used in the treatment of allergic rhinitis (AR). This study aimed to determine the expression of 48 miRNAs in patients with AR undergoing grass pollen SCIT and investigate relations with clinical outcomes. Methodology: Expression of selected miRNAs was determined using RT-PCR in the full blood of 16 patients with AR and seven healthy controls. Results: miR-136, miR-208 and miR-190 were upregulated in the AR group. After 6 months of SCIT, significant downregulation of some proinflammatory miRNAs and upregulation of several miRNAs regulating Th1/Th2 balance were found. No differences were found between good and poor responders. Conclusion: miRNAs may play a regulatory role in SCIT, leading to tolerance induction.

Allergen Immunotherapy in Pediatric Respiratory Allergy

Purpose of Review

Atopic diseases such as asthma and allergic rhinitis are highly prevalent in children. Common triggers include tree and grass pollens, house dust mites, molds, and animal dander. These diseases are most often treated symptomatically; however, many patients show partial or poor response and require long-term medication use. Allergen immunotherapy (AIT) stands as the only treatment modality that can alter the underlying disease process and potentially offer a cure. In this review article, we discuss the merits of AIT with particular emphasis on its efficacy and safety in pediatric patients. We also discuss the challenges for AIT implementation and present an overview of current research that aims at improving its applicability for the treatment of allergic diseases.

Recent Findings

Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are both safe and efficacious treatment options in children with allergic rhinitis and allergic asthma. Additionally, AIT has efficacy in preventing the development of asthma in children. Although there are clear advantages with AIT, there are challenges to overcome to optimize treatment. Solutions include improved diagnostics with pre-treatment biomarkers and molecular multiplex assays, biomarkers for prediction of response (e.g., basophil activation markers), improved allergen immunogenicity with the use of recombinant AIT, adjuvants, and allergoids, and lastly improved safety with the concurrent use of omalizumab.

Summary

AIT has shown safety and efficacy in major clinical trials for the treatment of allergic rhinitis and allergic asthma in children. AIT provides a curative treatment option for atopic disorders and should be considered in children with allergic rhinitis and allergic asthma. There are many continued advances being made in the field of allergy to further improve the safety and efficacy profile and shorten the duration of AIT treatment.

Changes in Immunologic Indicators During Allergen-Specific Immunotherapy for Allergic Rhinitis and Determinants of Variability: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

To date, there are no generally recognized biomarkers for allergen immunotherapy (AIT) and even the changes in immunological indicators during AIT are inconsistent in different publications.

OBJECTIVE

This study was conducted to quantify the immunological changes that occur during AIT and identify the determinants of heterogeneity.

METHODS

Randomized controlled trials of AIT published in the past 10 years were searched in Medline, Embase and Cochrane CENTRAL. Data on immunological indicators were extracted, and the characteristics of the included studies were collected. Meta-analysis and meta-regression were conducted for each indicator. The study was registered on the PROSPERO website (CRD42020176127).

RESULTS

We reviewed 1898 studies. Forty-six studies met the inclusion criteria, and 31 studies were included in the quantitative analyses. Subset analyses by time demonstrated that serum allergen-specific IgE (sIgE) of AIT patients increased in the first 12 months, then decreased and became slightly lower than that of control patients. Allergen-specific IgG4 (sIgG4) was elevated in the AIT group during and after treatment. IgE-blocking factor (IgE-BF) was increased and IgE-facilitated allergen binding (IgE-FAB) was reduced in AIT patients. Both of them of the 2 factors were associated with clinical efficacy in the multivariate regression analysis. sIgE/sIgG4 decreased in AIT patients, while there was no change in total IgE.

CONCLUSION

The levels of serum sIgE and sIgG4 during AIT showed a time-dependent pattern. IgE-BF and IgE-FAB should be further investigated as biomarkers for predicting and monitoring AIT efficacy.

Evaluation of safety and tolerability of a rush up-dosing allergen-specific immunotherapy with grass pollen, birch, hazel, and alder allergoid in children with allergic rhinoconjunctivitis, with or without asthma

Background:

Usually, the number of injections required to achieve the maintenance dose in subcutaneous immunotherapy (SCIT) is relatively small for some of the currently used allergens, but this may still be uncomfortable for patients, thus compromising adherence and compliance.

Objective:

The purpose of this study was to evaluate the safety and tolerability of a dose acceleration of a conventional induction schedule using an allergoid extract of grass pollen, birch, hazel, and alder, needed to achieve the ideal maintenance dose.

Methods:

In this open-label study, 34 patients with allergic rhinoconjunctivitis, with or without asthma, were treated with SCIT using an allergoid for grass pollen or birch or mix trees with an increase in accelerated induction dose comprising only 3 injections, one per week, compared to a conventional induction pattern in five injections (once a week). Safety determination was assessed by evaluating local and systemic adverse events. Tolerability was evaluated by patients and physicians who performed the treatment.

Results:

No treatment-related adverse events were observed in any of the patients undergoing rush SCIT. No local reactions, no systemic reactions of any degree (WAO Grade) have been observed. Tolerability has always been rated as very good by both patients and physician.

Conclusions:

The induction phase, needed to achieve the monthly maintenance dose for a pollen extract, can be greatly accelerated, ensuring a tolerability comparable to that of the conventional schedule. (www.actabiomedica.it)

Presentation, diagnosis, and the role of subcutaneous and sublingual immunotherapy in the management of ocular allergy

Allergic eye disease or ocular allergy is a debilitating condition with a significant impact on quality of life and productivity. As atopy continues to be on the rise, primary care providers are likely to encounter increasing numbers of patients with allergic eye disease. This review outlines the classification and pathophysiology of allergic eye disease and its clinical presentation. This paper does not detail traditional first-line therapies of allergic eye disease but describes the interdisciplinary management between the eye-care provider and allergist. It is recommended that patients with ongoing signs and symptoms of ocular allergy despite first-line therapies be referred for allergen immunotherapy, as it is highly effective for treatment of allergic eye disease. Through induction of immune tolerance, allergen immunotherapy is a disease-modifying therapy that can result in long-term improvement of ocular allergy. A thorough literature review was conducted on the efficacy and safety of allergen immunotherapy, including subcutaneous immunotherapy and sublingual immunotherapy, and its role in allergic eye disease.

Molecular approaches to allergen-specific immunotherapy: Are we so far from clinical implementation?

Conventional allergen-specific immunotherapy (AIT), based on administrations of allergen extracts, represents up to now the unique protocol for the desensitization of allergic patients. Whereas the effectiveness of AIT was evidenced for the treatment of allergic rhinitis and allergic asthma, such strategy remains experimental for food allergies up to now. However, important issues are commonly associated with AIT as the quality of natural allergen extracts, the long duration and adverse side-effects which negatively affect successful desensitization together with the patient compliance. The rapid progression of molecular allergology made possible the quest of safer, shorter and more effective immunotherapeutic approaches. The aim of this review was to provide an update on these different innovative recombinant derivatives including their efficacy but also their limitations. Despite promising preclinical and early clinical studies, the absence of convincing data in large phase III trials precludes so far the translation of these immunotherapeutic candidates into the clinic.

Allergen-specific Immunotherapy for Inhalant Allergens in Children

Allergen-specific immunotherapy (AIT) for aeroallergens consists of the administration of standardized allergen extracts to patients with respiratory IgE-mediated diseases to the same allergen in order to achieve immune tolerance to the allergen and prevent the onset of symptoms. AIT is usually delivered by sublingual (SLIT), subcutaneous (SCIT) route. AIT with one or multiple allergens currently represents the only causal treatment able to change the natural history of allergic airway diseases. Significant progresses have been made in terms of AIT efficacy and safety. In this paper, mechanisms of action, indication and side effects of allergen immunotherapy are reviewed. SLIT and SCIT have been found to be effective in the treatment of asthma and rhinoconjunctivitis due to inhalant allergens. The route of AIT administration should be selected on availability, cost (dependent from the local health system), tolerability (better for SLIT), patient's preference (injections are less accepted in young children), and adherence (higher for SCIT beyond pediatric age). However, it should be taken into account that metanalyses on AIT do not consider that effectiveness and safety depend upon the product chosen for treatment. Each product should be separately assessed to avoid generalization on administration routes or age group that may affect the decision.

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.

Familial Success in Allergen Desensitization

INTRODUCTION

Allergic rhinitis (AR) is a widely prevalent immunoglobulin E-mediated inflammatory nasal condition resulting from reexposure to an allergen in a sensitized individual. The genetic associations behind AR and other allergic conditions have been studied. However, familial success with AR therapies, specifically allergen desensitization through subcutaneous immunotherapy (SCIT), has never been reported in the literature. Pharmocogenetics has been gradually applied to link heritable genetic variants with drug responses, such as intergenic region variants APOBEC3B and APOBEC3C and β2-adrenergic receptor and glycoprotein ADAM33 polymorphisms as predictive biomarkers for biologic treatment response in asthma. We provide the first reported survey of familial success with SCIT.

METHODS

We administered a month-long, institutional review board-approved (20190493) questionnaire to 200 adult patients receiving SCIT in a suburban allergy/immunology practice. The anonymous survey inquired about demographics, target allergens for their SCIT, current symptom improvement on SCIT, and family history of allergies and SCIT management.

RESULTS

Twenty-six percent (52 of 200, 26%) SCIT patients reported familial success with the same allergy treatment modality. AR diagnosis and symptom improvement from SCIT was similar among previous/same (18 of 52, 38%; 26 of 52, 54%) and subsequent (10 of 52, 21%; 19 of 52, 40%) generations of family members. A combination of seasonal and perennial allergies was most prevalent (81%) among this population.

CONCLUSION

In a subpopulation of SCIT patients, there appears to be a familial success rate with this allergen desensitization treatment. This is the first reported pharmocogenetic evidence of assessing hereditary influence on effective AR therapy. Understanding pharmacogenetic associations involved with SCIT may improve allergists' recommendations for this treatment option.

Short course of grass allergen peptides immunotherapy over 3 weeks reduces seasonal symptoms in allergic rhinoconjunctivitis with/without asthma: A randomized, multicenter, double-blind, placebo-controlled trial

Background

Immunotherapy with peptide hydrolysates from Lolium perenne (LPP) is an alternative treatment for seasonal allergic rhinitis with or without asthma. The aim of this study was to assess the clinical efficacy and safety of a cumulative dose of 170 μg LPP administered subcutaneously over 3 weeks.

Methods

In a randomized, double‐blind, placebo‐controlled trial, 554 adults with grass pollen rhinoconjunctivitis were randomized (1:2 ratio) to receive 8 subcutaneous injections of placebo or 170 μg LPP administered in increasing doses in 4 visits over 3 weeks. The primary outcome was the combined symptom and medication score (CSMS) measured over the peak pollen season. Reactivity to conjunctival provocation test (CPT) and quality of life (QOL) was assessed as secondary endpoints.

Results

The mean reduction in CSMS in the LPP vs placebo group was −15.5% (P = .041) during the peak period and −17.9% (P = .029) over the entire pollen season. LPP‐treated group had a reduced reactivity to CPT (P < .001) and, during the pollen season, a lower rhinoconjunctivitis QOL global score (P = .005) compared with placebo group. Mostly mild and WAO grade 1 early systemic reaction (ESR) were observed ≤30 minutes in 10.5% of LPP‐treated patients, whereas 3 patients with a medical history of asthma (<1%) experienced a serious ESR that resolved with rescue medication.

Conclusion

Lolium perenne pollen peptides administered over 3 weeks before the grass pollen season significantly reduced seasonal symptoms and was generally safe and well‐tolerated.

New approaches to allergen immunotherapy

OBJECTIVE

New insights into mechanisms should enable strategic improvement of allergen immunotherapy, aiming to make it safer, faster, more effective, and able to induce long-term tolerance. We review novel approaches with potential to translate into clinical use.

DATA SOURCES

Database searches were conducted in PubMed, Scopus, and Google Scholar.

STUDY SELECTIONS

Search terms were based on current and novel approaches in immunotherapy. Literature was selected primarily from recent randomized double-blinded placebo-controlled trials and meta-analyses.

RESULTS

Alum, microcrystalline tyrosine, and calcium phosphate are adjuvants in current use. Toll-like receptor-4 agonists combined with allergen have potential to shorten duration of treatment. Other novel adjuvants, nanoparticles, and virus-like particles in combination with allergen have shown early promise. Omalizumab lessens systemic side effects but does not improve efficacy. Intralymphatic immunotherapy for aeroallergens, epicutaneous immunotherapy for food allergens, and use of modified allergens (allergoids), recombinant allergens (and hypoallergenic variants), and T- and B-cell peptide approaches have shown evidence of efficacy and permitted shortened courses but have only rarely been compared with conventional extracts.

CONCLUSION

Novel routes of immunotherapy, use of modified allergens, and combination of allergens with immunostimulatory adjuvants or immune modifiers have been developed to augment downregulation of T-helper cell type 2 immunity and/or induce "protective" blocking antibodies. Although these strategies have permitted shortened courses, confirmatory phase 3 trials are required to confirm efficacy and safety and head-to-head trials are required for comparative efficacy. Currently, subcutaneous and sublingual immunotherapies using in-house standardized crude extracts remain the only approaches proved to induce long-term tolerance.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Accelerated subcutaneous immunotherapy in pediatric population - Systematic review

BACKGROUND

Accelerated subcutaneous immunotherapy (SCIT) schedules represent an alternative to conventional SCIT, providing immunotherapy benefits in a shorter period of time. The objectives of this systematic review were to assess clinical and immunological efficacy as well as safety of accelerated SCIT build-up schedules for the treatment of respiratory allergy in pediatric patients.

METHODS

Studies were located by searching PubMed, using "immunotherapy" and "desensitization" as keywords. The selection of studies, published from January 1st, 2006, to December 31th, 2015, was performed in two stages: screening of titles and abstracts, and assessment of the full papers identified as relevant, considering the inclusion criteria. Data were extracted in a standardized way and synthesized qualitatively to assess efficacy and safety of accelerated schedules in respiratory allergy.

RESULTS

Eleven trials were included: two evaluated rush SCIT and nine assessed cluster SCIT. This review demonstrated that rush and cluster schedules are clinically and immunological efficacious, with faster effect than conventional schedules. No relevant difference with respect to clinical outcomes was noticed between subgroups (pediatric, adult and mixed populations). Regarding safety, most local adverse reactions were mild and there were neither life-threatening systemic reactions nor fatal events. No relevant differences in the incidence and severity of either local or systemic reactions between the accelerated schedule group and control group were registered.

CONCLUSIONS

Accelerated SCIT build-up schedules are effective in the treatment of respiratory allergy in pediatric patients, representing a safe alternative to the conventional schedules with the advantage of achieving clinical effectiveness sooner.

Allergen immunotherapy for allergic rhinoconjunctivitis: A systematic review and meta-analysis

BACKGROUND

The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis. To inform the development of clinical recommendations, we undertook a systematic review to assess the effectiveness, cost-effectiveness, and safety of AIT in the management of allergic rhinoconjunctivitis.

METHODS

We searched nine international biomedical databases for published, in-progress, and unpublished evidence. Studies were independently screened by two reviewers against predefined eligibility criteria and critically appraised using established instruments. Our primary outcomes of interest were symptom, medication, and combined symptom and medication scores. Secondary outcomes of interest included cost-effectiveness and safety. Data were descriptively summarized and then quantitatively synthesized using random-effects meta-analyses.

RESULTS

We identified 5960 studies of which 160 studies satisfied our eligibility criteria. There was a substantial body of evidence demonstrating significant reductions in standardized mean differences (SMD) of symptom (SMD -0.53, 95% CI -0.63, -0.42), medication (SMD -0.37, 95% CI -0.49, -0.26), and combined symptom and medication (SMD -0.49, 95% CI -0.69, -0.30) scores while on treatment that were robust to prespecified sensitivity analyses. There was in comparison a more modest body of evidence on effectiveness post-discontinuation of AIT, suggesting a benefit in relation to symptom scores.

CONCLUSIONS

AIT is effective in improving symptom, medication, and combined symptom and medication scores in patients with allergic rhinoconjunctivitis while on treatment, and there is some evidence suggesting that these benefits are maintained in relation to symptom scores after discontinuation of therapy.

Chinese Guideline on allergen immunotherapy for allergic rhinitis

The present document is based on a consensus reached by a panel of experts from Chinese Society of Allergy (CSA) and Chinese Allergic Rhinitis Collaborative Research Group (C2AR2G). Allergen immunotherapy (AIT), has increasingly been used as a treatment for allergic rhinitis (AR) globally, as it has been shown to provide a long-term effect in improving nasal and ocular symptoms, reducing medication need, and improving quality of life. AIT is currently the only curative intervention that can potentially modify the immune system in individuals suffering from AR and prevent the development of new sensitization and the progression of disease from AR to asthma. Although the use of AIT is becoming more acceptable in China, to date no AR immunotherapy guideline from China is available for use by the international community. This document has thus been produced and covers the main aspects of AIT undertaken in China; including selection of patients for AIT, the allergen extracts available on the Chinese market, schedules and doses of allergen employed in different routes of AIT, assessment of effect and safety, patients' administration and follow-up, and management of adverse reactions. The Chinese guideline for AR immunotherapy will thus serve as a reference point by doctors, healthcare professionals and organizations involved in the AIT of AR in China. Moreover, this guideline will serve as a source of information for the international community on AIT treatment strategies employed in China.

Dexpanthenol: An Overview of its Contribution to Symptom Relief in Acute Rhinitis Treated with Decongestant Nasal Sprays

Nasal blockage is the most bothersome symptom of acute rhinitis. Nasal decongestant sprays containing alpha-sympathomimetics, such as oxymetazoline and xylometazoline, have a rapid onset of action. However, this effect decreases with repeated application and, furthermore, the ciliary function of the nasal mucosa is practically paralyzed. Dexpanthenol promotes cell proliferation and protects the epithelium. Combining these two agents has demonstrated beneficial synergetic effects on the symptoms of acute rhinitis. In a post hoc analysis of a large-scale double-blind, active-controlled study including 152 patients, we could demonstrate that the benefit of added dexpanthenol appears as early as on the third day of the combined application of xylometazoline and dexpanthenol in terms of complete or near-to-complete freedom from symptoms. After 5 days, 47% of the patients were cured under the combined treatment compared with only 1% under xylometazoline monotherapy. These data show that the addition of dexpanthenol to an alpha-sympathomimetic nasal spray not only improves its tolerability but also further increases its effectiveness and leads to expedited cure.

FUNDING

Klosterfrau Healthcare Group.

Allergen Immunotherapy Clinical Trial Outcomes and Design: Working Toward Harmonization of Methods and Principles

Progress has been made in the harmonization of efficacy and safety outcome measures for allergen immunotherapy (AIT) trials, but unresolved issues still remain. Furthermore, there are discrepancies in recommendations from professional medical societies and regulatory agencies regarding requirements for AIT trials. In this article, we reviewed published recommendations and current data from recent clinical trials, as well as the criteria applied by regulatory authorities for approval of AIT products, to provide updated considerations for conducting phase 3 AIT trials. Topics discussed include analysis of outcomes and trial designs for pediatric and asthma indications, as well as trial designs for perennial allergic rhinoconjunctivitis. In addition, the need for harmonization of safety reporting is emphasized. Considerations presented in this article may further effort to find common ground among professional medical societies and government agencies in developing future recommendations for AIT trial design.

Defining pollen exposure times for clinical trials of allergen immunotherapy for pollen-induced rhinoconjunctivitis - an EAACI position paper

BACKGROUND

Clinical efficacy of pollen allergen immunotherapy (AIT) has been broadly documented in randomized controlled trials. The underlying clinical endpoints are analysed in seasonal time periods predefined based on the background pollen concentration. However, any validated or generally accepted definition from academia or regulatory authorities for this relevant pollen exposure intensity or period of time (season) is currently not available. Therefore, this Task Force initiative of the European Academy of Allergy and Clinical Immunology (EAACI) aimed to propose definitions based on expert consensus.

METHODS

A Task Force of the Immunotherapy and Aerobiology and Pollution Interest Groups of the EAACI reviewed the literature on pollen exposure in the context of defining relevant time intervals for evaluation of efficacy in AIT trials. Underlying principles in measuring pollen exposure and associated methodological problems and limitations were considered to achieve a consensus.

RESULTS

The Task Force achieved a comprehensive position in defining pollen exposure times for different pollen types. Definitions are presented for 'pollen season', 'high pollen season' (or 'peak pollen period') and 'high pollen days'.

CONCLUSION

This EAACI position paper provides definitions of pollen exposures for different pollen types for use in AIT trials. Their validity as standards remains to be tested in future studies.

Increasing time interval and decreasing allergen dose interval improves ex vivo desensitization of human blood basophils

BACKGROUND

Desensitization is a method for inducing temporary tolerance to allergen. The mechanism underlying desensitization is yet to be established.

METHODS

Basophil granulocytes in whole blood from grass pollen allergic subjects were desensitized ex vivo by sequential addition of increasing allergen concentrations. At each step basophil activation (CD193 ⁺ CD63⁺ ) was monitored with and without (background activation) allergen challenge at optimal concentration. The sequential desensitization protocol was compared to two single-dose desensitization protocols with threshold and subthreshold allergen concentrations. Incubation intervals and allergen concentrations were varied in order to optimise the protocol.

RESULTS

Sequential desensitization effectively reduced basophil response. The single-dose subthreshold protocol and single-dose threshold protocol did not reduce basophil activation with optimal allergen challenge from a mean 57.1 (95% CI: 32.7 - 81.5) to 50.4% (95% CI: 16.3 - 84.4; n = 5; P = 0.43) and 45.0% (95% CI: 23.1 - 66.9; P = 0.14) respectively, while the sequential desensitization protocol reduced activation to a mean 37.2% (95% CI: 16.3 - 58.1; P = 0.018). Reducing incubation time from 10 to 5 minutes increased mean background activation from 22.4 (95% CI: 11.7 - 33.1) to 30.0% (95% CI: 19.7 - 40.3; n = 5; P = 0.026). Increasing time intervals from 10 to 20 minutes reduced background activation from 30.9 (95% CI: 22.8 - 39.0) to 21.9% (95% CI: 16.0 - 27.7; n = 5; P = 0.020). Increasing allergen concentration intervals from 2-fold to 5- and 10-fold did not have significant effect on basophil activation.

CONCLUSIONS

Sequential desensitization ex vivo effectively attenuates the basophil response to allergen. Increasing the time spent at each step improves desensitization. This protocol could be valuable for investigation the mechanism of desensitization. © 2016 International Clinical Cytometry Society.

An accelerated dose escalation with a grass pollen allergoid is safe and well-tolerated: a randomized open label phase II trial

Background

The number of injections in the dose escalation of subcutaneous immunotherapy (SCIT) is small for some currently used hypoallergenic allergoids, but can still be inconvenient to patients and can impair compliance. The aim of this trial was to compare safety and tolerability of an accelerated to the conventional dose escalation scheme of a grass pollen allergoid.

Methods

In an open label phase II trial, 122 patients were 1:1 randomized for SCIT using a grass pollen allergoid with an accelerated dose escalation comprising only 4 weekly injections (Group I) or a conventional dose escalation including 7 weekly injections (Group II). Safety determination included the occurrence of local and systemic adverse events. Tolerability was assessed by patients and physicians.

Results

Treatment-related adverse events were observed in 22 (36.1 %) patients in Group I and 15 (24.6 %) in Group II. Local reactions were reported by 18 patients in Group I and 11 in Group II. Five Grade 1 systemic reactions (WAO classification) were observed in Group I and 2 in Group II. Grade 2 reactions occurred 3 times in Group I and 2 times in Group II. Tolerability was rated as “good” or “very good” by 53 (86.9 %) patients in Group I and 59 (100 %) in Group II by investigators. Forty-eight patients in Group I (80.0 %) and 54 in Group II (91.5 %) rated tolerability as “good” or “very good”.

Conclusions

The dose escalation of a grass pollen allergoid can be accelerated with safety and tolerability profiles comparable to the conventional dose escalation.

Ultrarush schedule of subcutaneous immunotherapy with modified allergen extracts is safe in paediatric age

Background

Traditional subcutaneous immunotherapy up dosing with allergenic extracts has been shown to be associated with frequent adverse reactions. In recent studies it has been demonstrated that using modified extracts, namely allergoids, it is a safe and effective procedure particularly on accelerated schedules. However data assessing its safety in paediatric age is scarce.

Objective

To evaluate the safety profile in paediatric population of using modified allergen extracts, in an ultrarush schedule, to reach the maintenance dose in the first day.

Methods

We included children undergoing treatment with subcutaneous immunotherapy during a five-year period, using modified aeroallergen extracts, depigmented, polymerized with glutaraldehyde and adsorbed on aluminium hydroxide using an ultrarush induction phase. The type of adverse reactions during the ultrarush protocol was recorded.

Results

We studied 100 paediatric patients (57 males) with a mean age of 11.6 years (5 to 18 years; standard deviation, 3.3), all with moderate to severe persistent rhinitis, with or without allergic conjunctivitis, asthma and atopic eczema, sensitized to mites and/or pollens. All reached the maintenance dose of 0.5 mL in the first day, except 1 child. During the ultrarush protocol the total number of injections was 199. There were 21 local adverse reactions in 11 patients, 11 immediate and 10 delayed; from those, had clinical relevance 1 immediate and 4 delayed. Systemic reactions were recorded in 2 cases, both immediate and mild.

Conclusion

The ultrarush protocol, without premedication, was a safe alternative to be used in paediatric age during the induction phase of subcutaneous immunotherapy using allergoid depigmented extracts.

Timothy grass pollen therapeutic vaccine: optimal dose for subcutaneous immunotherapy

AIMS

To establish the optimal dose of Phleum pratense subcutaneous immunotherapy (SCIT) in patients with allergic rhinoconjunctivitis with/without asthma.

MATERIALS & METHODS

One hundred and fifty-one patients were randomized to receive SCIT 0.25, 0.5, 1.0, 2.0 or 4.0 skin-prick test units (SPT) or placebo. The primary end point was the variation in the concentration of Phleum pratense extract needed to produce a positive nasal provocation test from baseline (V0) to final visit (FV).

RESULTS

After 17 weeks, a dose-dependent trend was apparent in the concentration of P. pratense extract needed to produce a positive nasal provocation response. Systemic adverse reactions occurred with 3.2% of administered doses. Grade III (n = 2) and IV (n = 2) events were observed only at the two highest doses.

CONCLUSION

P. pratense depot SCIT showed signs of clinical and immunological efficacy by dose-dependently decreasing the allergen sensitization rate. Risk-benefit favored doses below 1.0 SPT units for confirmatory trials.

Safety and effect on reported symptoms of depigmented polymerized allergen immunotherapy: a retrospective study of 2927 paediatric patients

BACKGROUND

Allergen immunotherapy (AIT) is effective treatment for allergic diseases, and subcutaneous use of depigmented polymerized extracts may allow rapid up-dosing and safe therapy. To date, there is little information on their safety and clinical effects for children and adolescents with allergic disease.

METHODS

We performed a retrospective survey of patient notes of 2927 children and adolescents across 136 centres who had received subcutaneous AIT (SCIT) with depigmented polymerized extracts to pollen or mite allergens for at least 1 yr to collect documentation on safety and clinical symptoms.

RESULTS

16.3% percent of patients had local reactions, of these 148 were larger than 12 cm in diameter. Systemic reactions were documented in 1.6% of children and in 0.8% of adolescents. There were no documented cases of anaphylactic shock. There were significant reductions in the frequency of patients with recorded nasal symptoms over time of treatment. Moreover, the prescribing rate of rescue medication was reduced over the course of SCIT.

CONCLUSION

These 'real-life' data from a large retrospective analysis including 2927 children and adolescents with pollen- and/or mite-induced allergic rhinoconjunctivitis with/or without allergic asthma indicate that AIT with depigmented polymerized extracts is well tolerated, and they are compatible with clinical response.

Conjunctival provocation tests: a predictive factor for patients' seasonal allergic rhinoconjunctivitis symptoms

BACKGROUND

No parameters currently exist that can reliably predict the impact of preseasonal immunotherapy on the symptoms occurring during the season.

OBJECTIVE

The purpose of our studies was to prove a correlation between preseasonal conjunctival allergen challenge and coseasonal primary clinical endpoints using the total combined score, ie, a combination of symptoms and medication score, as the primary outcome parameter.

METHODS

Twelve weeks before both the birch and the grass pollen seasons, 2 separate prospective, double-blind, randomized, controlled studies were conducted followed by posttrial observations for each study during the active season. In the studies, patients who reacted to conjunctival allergen challenge were treated with sublingual immunotherapy tablets that contain either birch and/or alder or grass pollen allergoids.

RESULTS

In all, 158 patients were included in the grass and 160 in the tree pollen study; of these, 100 and 109 patients, respectively, took part in the posttrial observations. When comparing patients with and without a positive reaction in the final conjunctival allergen challenge, the results revealed a significant difference in the total combined score (grass: P < .001; birch: P = .025). The same applied to the rescue medication score (P = .005; P = .025). A significant difference regarding the rhinoconjunctivitis symptom score was shown in the grass pollen study (P = .002), and the difference of well days was significant in the tree pollen study (P = .049).

CONCLUSION

When comparing patients based on their reaction to allergen challenge after immunotherapy, each study leads to similarly significant results. Therefore, conjunctival allergen challenge can be used effectively as a parameter to predict allergic rhinoconjunctivitis symptoms during the season in patients treated with preseasonal sublingual immunotherapy tablets. Whether this can be transferred to untreated patients needs to be determined.

Health economic comparison of SLIT allergen and SCIT allergoid immunotherapy in patients with seasonal grass-allergic rhinoconjunctivitis in Germany

BACKGROUND

Allergoids are chemically modified allergen extracts administered to reduce allergenicity and to maintain immunogenicity. Oralair® (the 5-grass tablet) is a sublingual native grass allergen tablet for pre- and co-seasonal treatment. Based on a literature review, meta-analysis, and cost-effectiveness analysis the relative effects and costs of the 5-grass tablet versus a mix of subcutaneous allergoid compounds for grass pollen allergic rhinoconjunctivitis were assessed.

METHODS

A Markov model with a time horizon of nine years was used to assess the costs and effects of three-year immunotherapy treatment. Relative efficacy expressed as standardized mean differences was estimated using an indirect comparison on symptom scores extracted from available clinical trials. The Rhinitis Symptom Utility Index (RSUI) was applied as a proxy to estimate utility values for symptom scores. Drug acquisition and other medical costs were derived from published sources as well as estimates for resource use, immunotherapy persistence, and occurrence of asthma. The analysis was executed from the German payer's perspective, which includes payments of the Statutory Health Insurance (SHI) and additional payments by insurants. Comprehensive deterministic and probabilistic sensitivity analyses and different scenarios were performed to test the uncertainty concerning the incremental model outcomes.

RESULTS

The applied model predicted a cost-utility ratio of the 5-grass tablet versus a market mix of injectable allergoid products of € 12,593 per QALY in the base case analysis. Predicted incremental costs and QALYs were € 458 (95% confidence interval, CI: € 220; € 739) and 0.036 (95% CI: 0.002; 0.078), respectively. Compared to the allergoid mix the probability of the 5-grass tablet being the most cost-effective treatment option was predicted to be 76% at a willingness-to-pay threshold of € 20,000. The results were most sensitive to changes in efficacy estimates, duration of the pollen season, and immunotherapy persistence rates.

CONCLUSIONS

This analysis suggests the sublingual native 5-grass tablet to be cost-effective relative to a mix of subcutaneous allergoid compounds. The robustness of these statements has been confirmed in extensive sensitivity and scenario analyses.

A high polymerized grass pollen extract is efficacious and safe in a randomized double-blind, placebo-controlled study using a novel up-dosing cluster-protocol

BACKGROUND

Cluster immunotherapy represents an interesting alternative to conventional up-dosing schedules because it allows achieving the maintenance dose within a shorter time interval. In this study, the efficacy and safety of cluster immunotherapy with a high polymerized allergen extract of a grass/rye pollen mixture have been evaluated in a randomized, double-blind, placebo-controlled, multicenter study.

METHODS

In total, 121 patients with allergic rhinoconjunctivitis due to grass pollen were randomized 1 : 1 to verum or placebo group. A short cluster up-dosing schedule of only 1 week was applied to achieve the maintenance dose which was administered monthly during the study period of 1 year. Total combined symptom and medication score (TCS) was defined as primary outcome parameter. Secondary outcome parameters were individual symptom and medication scores, 'well days,' global improvement as well as immunological effects and nasal allergen challenge. The safety profile was evaluated based on the European academy of allergy and clinical immunology grading system.

RESULTS

Significant reduction in the verum compared to the placebo group (intention-to-treat, population, verum: n = 55; placebo: n = 47) was found regarding TCS (P = 0.005), rhinoconjunctivitis total symptom score (RTSS, P = 0.006), and total rescue medication score (TRMS, P = 0.002). Additionally, secondary outcomes such as 'well days,' nasal challenge results, and increase of specific IgG4 were in favor of the active treatment. All systemic adverse reactions (0.8% of all injections in the verum group) were of mild intensity. No severe reactions related to the study medication were observed.

CONCLUSION

Cluster immunotherapy with high polymerized grass pollen extracts resulted in significant clinical efficacy and has been shown to be a safe treatment for grass pollen-allergic patients.

Recommendations for the standardization of clinical outcomes used in allergen immunotherapy trials for allergic rhinoconjunctivitis: an EAACI Position Paper

BACKGROUND

Allergen immunotherapy (AIT) has been thoroughly documented in randomized controlled trials (RCTs). It is the only immune-modifying and causal treatment available for patients suffering from IgE-mediated diseases such as allergic rhinoconjunctivitis, allergic asthma and insect sting allergy. However, there is a high degree of clinical and methodological heterogeneity among the endpoints in clinical studies on AIT, for both subcutaneous and sublingual immunotherapy (SCIT and SLIT). At present, there are no commonly accepted standards for defining the optimal outcome parameters to be used for both primary and secondary endpoints.

METHODS

As elaborated by a Task Force (TF) of the European Academy of Allergy and Clinical Immunology (EAACI) Immunotherapy Interest Group, this Position Paper evaluates the currently used outcome parameters in different RCTs and also aims to provide recommendations for the optimal endpoints in future AIT trials for allergic rhinoconjunctivitis.

RESULTS

Based on a thorough literature review, the TF members have outlined recommendations for nine domains of clinical outcome measures. As the primary outcome, the TF recommends a homogeneous combined symptom and medication score (CSMS) as a simple and standardized method that balances both symptoms and the need for antiallergic medication in an equally weighted manner. All outcomes, grouped into nine domains, are reviewed.

CONCLUSION

A standardized and globally harmonized method for analysing the clinical efficacy of AIT products in RCTs is required. The EAACI TF highlights the CSMS as the primary endpoint for future RCTs in AIT for allergic rhinoconjunctivitis.

Sublingual or subcutaneous immunotherapy for seasonal allergic rhinitis: an indirect analysis of efficacy, safety and cost

RATIONALE, AIMS AND OBJECTIVES

The standard of preventive care for poorly controlled seasonal allergic rhinitis (AR) is subcutaneous immunotherapy (SCIT) with allergen extracts, administered in a physician's office. As an alternative to SCIT, sublingual immunotherapy (SLIT) is now an option for patients with seasonal AR. Oralair, a SLIT tablet containing freeze-dried allergen extracts of five grasses [cocksfoot (Dactylis glomerata), meadow grass (Poa pratensis), rye grass (Lolium perenne), sweet vernal grass (Anthoxanthum odoratum) and timothy grass (Phleum pratense)], and Grazax, a SLIT tablet containing a standardized extract of grass pollen allergen from timothy grass (P pratenase), are two such agents currently available in many countries. However, head-to-head comparative data are not available. In this study, an indirect comparison on efficacy, safety and cost was undertaken between Oralair, Grazax and SCIT.

METHODS

A systematic review was conducted for double-blind placebo-controlled randomized trials evaluating Oralair, Grazax or SCIT in patients with grass-induced seasonal AR. Using placebo as the common control, an indirect statistical comparison between treatments was performed using meta regression analysis with active drug as the primary independent variable. An economic analysis, which included both direct and indirect costs for the Canadian setting, was also undertaken.

RESULTS

Overall, 20 placebo-controlled trials met the study inclusion criteria. The indirect analysis suggested improved efficacy with Oralair over SCIT [standardized mean difference (SMD) in AR symptom control = -0.21; P = 0.007] and Grazax (SMD = -0.18; P = 0.018). In addition, there were no significant differences in the risk of discontinuation due to adverse events between therapies. Oralair was associated with cost savings against year-round SCIT ($2471), seasonal SCIT ($948) and Grazax ($1168) during the first year of therapy.

CONCLUSIONS

Oralair has at least non-inferior efficacy and comparable safety against SCIT and Grazax at a lower annual cost.

Depigmented-polymerised allergoids favour regulatory over effector T cells: enhancement by 1α, 25-dihydroxyvitamin D3

Background

Allergen immunotherapy (SIT) is the only treatment for allergic disease capable of modifying disease long term. To reduce the risk of anaphylaxis from SIT, allergen-extracts have been modified by polymerisation with glutaraldehyde to reduce IgE binding. It is suggested that these allergoid extracts also have reduced T cell activity, which could compromise clinical efficacy. Effective SIT is thought to act through regulatory T cells (Tregs) rather than activation of effector T cells. There is no published data on the activity of modified extracts on Tregs.

Results

We compared the capacity of modified (depigmented-polymerised) versus unmodified (native) allergen extracts of grass pollen and house dust mite to stimulate proliferation/cytokine production and to modulate Treg/effector T cell frequency in cultures of peripheral blood mononuclear cells (PBMC), from volunteers sensitised to both allergens in vitro. Depigmented-polymerised allergen extracts stimulated less proliferation of PBMC, and reduced effector cell numbers after 7 days in culture than did native extracts. However, the frequency of Foxp3+ Tregs in cultures were similar to those seen with native extract so that ratios of regulatory to effector T cells were significantly increased in cultures stimulated with depigmented-polymerised extracts. Addition of 1α, 25-dihydroxyvitamin D3 further favoured Treg, and reduced effector cytokine production, but not interleukin-10.

Conclusions

Depigmented-polymerised allergen extracts appear to favour Treg expansion over activation of effector T cells and this may relate to their demonstrated efficacy and safety in SIT. 1α, 25-dihydroxyvitamin D3 further reduces effector T cell activation by allergen extracts and may be a useful adjuvant for SIT.

Safety and efficacy of tree pollen specific immunotherapy on the ultrarush administration schedule method using purethal trees

Background. Specific immunotherapy (SIT) with an ultrarush administration schedule with Purethal for tree pollen allergens has been evaluated to assess its efficacy and safety. Methods. The study group consisted of 22 patients with symptoms of allergic rhinitis and confirmed allergy to tree pollens. Patients were randomized and given an administration schedule of either ultrarush therapy or conventional preseasonal SIT. Treatment was performed during three consecutive years. Results. After three years of treatment, a similar reduction in nasal symptoms was observed; according to the visual analog scale, there was a decrease from 3.991 ± 0.804 points to 1.634 ± 0.540 in the ultrarush group and from 3.845 ± 0.265 to 1.501 ± 0.418 in the group desensitized using the conventional method (P > 0.05). There was also a comparable reduction in the use of relief drugs during pollen season and an increase in the serum concentration of IgG4 to tree pollens. No significant differences in the safety profile were observed. Conclusion. An administration schedule of ultrarush SIT with Purethal Trees is a safe treatment in preliminary observations. This therapy is comparable with conventional administration of SIT in the field of efficacy and safety.

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.

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.

Depigmented allergoids reveal new epitopes with capacity to induce IgG blocking antibodies

Background. The synthesis of allergen-specific blocking IgGs that interact with IgE after allergen immunotherapy (SIT) has been related to clinical efficacy. The objectives were to investigate the epitope specificity of IgG-antibodies induced by depigmented-polymerized (Dpg-Pol) allergoids and unmodified allergen extracts, and examine IgE-blocking activity of induced IgG-antibodies. Methods. Rabbits were immunized with native and Dpg-Pol extracts of birch pollen, and serum samples were obtained. Recognition of linear IgG-epitopes of Bet v 1 and Bet v 2 and the capacity of these IgG-antibodies to block binding of human-IgE was determined. Results. Serum from rabbits immunized with native extracts recognised 11 linear epitopes from Bet v 1, while that from Dpg-Pol-immunized animals recognised 8. For Bet v 2, 8 epitopes were recognized by IgG from native immunized animals, and 9 from Dpg-Pol immunized one. Dpg-Pol and native immunized serum did not always recognise the same epitopes, but specific-IgG from both could block human-IgE binding sites for native extract. Conclusions. Depigmented-polymerized birch extract stimulates the synthesis of specific IgG-antibodies which recognize common but also novel epitopes compared with native extracts. IgG-antibodies induced by Dpg-Pol effectively inhibit human-IgE binding to allergens which may be part of the mechanism of action of SIT.

Depigmented-polymerized mixed grass/birch pollen extract immunotherapy is effective in polysensitized patients

BACKGROUND

Although many patients with allergic rhinoconjunctivitis have symptoms due to sensitization with more than one pollen allergen, and mixed pollen extracts are widely used for allergen immunotherapy in practice, there are few published trials.

METHODS

We performed a 2-year multicentre, double-blind, placebo-controlled trial of subcutaneous immunotherapy with mixed depigmented-polymerized birch and grass pollen extract in 285 patients with allergic rhinoconjunctivitis symptomatic during both birch and grass pollen seasons. Primary outcome was combined symptom and medication score (SMS) assessed by daily visual analogue scales (VAS). Analysis included a placebo-based analysis examining the effect of treatment only on days when placebo patients were symptomatic.

RESULTS

There was a significant reduction in median SMS for actively treated patients (median 5.70 (interquartile range 2.62-10.02) compared with 7.07 (3.47-10.71) for placebo, P = 0.0385). Rhinitis quality-of-life scores were significantly better for active compared with placebo, and other secondary endpoints were not significantly different. Placebo-based analysis showed a 33.7% reduced SMS at year 2 for active treatment compared with placebo on days when placebo patients were symptomatic. Both birch pollen- and grass pollen-specific IgG4 increased with active treatment.

CONCLUSIONS

This study shows efficacy of mixed pollen extracts for immunotherapy for patients symptomatic to both birch and grass pollen allergens. The relatively modest effect may reflect 50% dose reduction for each allergen in the mixture. It supports VAS for symptom assessment and placebo-based analysis as useful for the analysis of immunotherapy trials. The safety of modified extracts may allow study of mixed extracts without dose reduction to improve efficacy.

Accelerated immunotherapy schedules

Rush and cluster immunotherapy schedules are accelerated immunotherapy build-up schedules. A cluster immunotherapy schedule involves the patient receiving several allergen injections (generally 2-4) sequentially in a single day of treatment on nonconsecutive days. The maintenance dose is generally reached in 4-8 weeks. In rush immunotherapy protocols, higher doses are administered at 15- to 60-min intervals over a 1- to 3-day period until the maintenance dose is achieved. This review will serve as an update for accelerated immunotherapy schedules. The review will include recent investigations demonstrating the safety of cluster schedules in atopic dermatitis, pediatric patients, and inhalant allergen mixtures and an accelerated protocol utilizing an infusion pump for allergen delivery. There has also been further elucidation on the immunological changes which occur during accelerated immunotherapy. Finally, new studies analyzing systemic reaction risk factors are discussed.

Intranasal, liposome-adjuvanted cockroach allergy vaccines made of refined major allergen and whole-body extract of Periplaneta americana

BACKGROUND

Cockroach (CR) allergens frequently cause severe asthma in CR-sensitized subjects. Allergen-specific immunotherapy causes a shift of allergic Th2 responses towards Th1 and/or regulatory T cell (Treg) responses which reduce airway inflammation and prevent disease progression. Data are relatively limited on immunotherapy via CR allergy vaccine.

METHODS

The therapeutic efficacy of an intranasal liposome-adjuvant vaccine made of a refined Periplaneta americana arginine kinase (AK) was compared to the liposome-entrapped P. americana crude extract (CRE) vaccine. Adult BALB/c mice were rendered allergic to CRE. Three allergic mouse groups were immunized intranasally on alternate days with 8 doses of liposome-entrapped CRE (L-CRE), liposome-entrapped AK and placebo, respectively. One week later, all mice received a nebulized CRE provocation. Evaluation of vaccine efficacy was performed 1 day after provocation.

RESULTS

Liposome-entrapped native AK attenuated airway inflammation after the CRE provocation and caused a shift of allergic Th2 to Th1 and Treg responses. The L-CRE also induced a shift from the Th2 to the Th1 response but did not induce a Treg response and could not attenuate the airway inflammation upon allergen reexposure.

CONCLUSIONS

Intranasal liposome-adjuvant CR allergy vaccine containing native AK (Per a 9) is better than L-CRE in attenuating allergic airway inflammation. The findings of this study not only document a more comprehensive and beneficial immune response induced by the refined allergen vaccine but also raise the point that the shift from the Th2 to the Th1 response alone might not correlate with improved airway histopathology, clinical outcome and quality of life.

Immunologic effect and tolerability of intra-seasonal subcutaneous immunotherapy with an 8-day up-dosing schedule to 10,000 standardized quality-units: a double-blind, randomized, placebo-controlled trial

BACKGROUND

International guidelines recommend that allergen-specific immunotherapy for pollen-induced rhinoconjunctivitis is initiated preseasonally. However, because subjects often present to physicians with allergy symptoms during the pollen season, "within-season" initiation of specific immunotherapy is of special interest.

OBJECTIVE

We evaluated the immunomodulatory effects and tolerability of subcutaneous immunotherapy (SCIT) with Standardized Quality (SQ) 6-grass mix and rye allergen extract, using an 8-day intra-seasonal up-dosing schedule to 10,000 SQ-units (SQ-U).

METHODS

In a 9-week, multicenter, randomized, double-blind, placebo-controlled trial, adults (mean age, 34.6 years; 99.3% whites) with grass pollen-induced rhinoconjunctivitis (mean disease duration, 15.1 years) were randomized 3:1 to receive SCIT or placebo. Treatment was initiated during the 2008 pollen season, with an 8-day up-dosing from 100 to 10,000 SQ-U (6 daily injections) followed by 2 maintenance injections of 10,000 SQ-U at intervals of 2 and 4 weeks, respectively. The primary end point examined immunologic effects, assessing the difference in IgE-blocking factor (serum components competing with IgE for allergen binding) between SCIT and placebo at week 9. Secondary/explorative end points included the difference in IgE-blocking factor, specific IgG(4), and specific IgE at various times. Tolerability (adverse events, local and systemic allergic reactions) of the up-dosing schedule was also evaluated.

RESULTS

Of the 148 treated subjects 144 (SCIT n = 109; placebo n = 35) were analyzed for the primary parameter. Immunologic response (significantly higher increase in IgE-blocking factor and IgG(4) levels) occurred with SCIT versus placebo at week 9 (IgE-blocking factor, P = 0.0017; IgG(4,)P = 0.0215). Significant differences were observed as early as week 3. AEs were reported in 60.7% of SCIT- and 30.6% of placebo-treated subjects, with no treatment-related serious AEs. Local allergic reactions occurred in 46.4% of SCIT and 8.3% of placebo subjects (χ(2) test, P < 0.0001). No significant difference was observed between groups in the incidence of systemic reactions (7.1% SCIT vs 5.6% placebo; χ(2) test, P = 0.7413).

CONCLUSIONS

This trial provides the first description of short (8-day) intra-seasonal up-dosing with SCIT, which induced immunologic effects after only 3 weeks, and was generally well tolerated, although it induced a marked increase in the rate of local reactions compared with placebo. ClinicalTrials.gov identifier NCT00807547; ALK trial ID SHX0562.

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.