Update on allergy immunotherapy: American Academy of Allergy, Asthma & Immunology/European Academy of Allergy and Clinical Immunology/PRACTALL consensus report

Allergen-Specific Immunotherapy for Respiratory Allergy in Children: Unmet Needs and Future Goals

Allergen-specific immunotherapy for the treatment of respiratory allergy is currently supported, at least for selected products, by evidence of efficacy and effectiveness in the pediatric age. However, unmet needs remain in terms of administration regimens, duration of treatment, biomarkers, and preventive effects. These knowledge gaps need to be urgently addressed to provide pediatricians and pediatric allergists with more definite recommendations for the use of this treatment in children. This article critically appraises the most relevant debated issues on allergen-specific immunotherapy in children, focusing on allergen standardization procedures, heterogeneity of clinical studies, and regulatory and pharmacoeconomic aspects.

Molecular fingerprinting of complex grass allergoids: size assessments reveal new insights in epitope repertoires and functional capacities

Background

Subcutaneous allergen immunotherapy (SCIT) is a well-documented treatment for allergic disease which involves injections of native allergen or modified (allergoid) extracts. The use of allergoid vaccines is a growing sector of the allergy immunotherapy market, associated with shorter-course therapy. The aim of this study was the structural and immunological characterisation of group 1 (Lol p 1) IgG-binding epitopes within a complex mix grass allergoid formulation containing rye grass.

Methods

HP-SEC was used to resolve a mix grass allergoid preparation of high molecular weight into several distinct fractions with defined molecular weight and elution profiles. Allergen verification of the HP-SEC allergoid fractions was confirmed by mass spectrometry analysis. IgE and IgG immunoreactivity of the allergoid preparations was explored and Lol p 1 specific IgG-binding epitopes mapped by SPOT synthesis technology (PepSpot™) with structural analysis based on a Lol p 1 homology model.

Results

Grass specific IgE reactivity of the mix grass modified extract (allergoid) was diminished in comparison with the mix grass native extract. A difference in IgG profiles was observed between an intact mix grass allergoid preparation and HP-SEC allergoid fractions, which indicated enhancement of accessible reactive IgG epitopes across size distribution profiles of the mix grass allergoid formulation. Detailed analysis of the epitope specificity showed retention of six Lol p 1 IgG-binding epitopes in the mix grass modified extract.

Conclusion

The structural and immunological changes which take place following the grass allergen modification process was further unravelled revealing distinct IgG immunological profiles. All epitopes were mapped on the solvent exposed area of Lol p 1 homology model accessible for IgG binding. One of the epitopes was identified as an ‘immunodominant’ Lol p 1 IgG-binding epitope (62-IFKDGRGCGSCFEIK-76) and classified as a novel epitope. The results from this study support the concept that modification allows shorter-course therapy options as a result of providing an IgG epitope repertoire important for efficacy. Additionally, the work paves the way to help further develop methods for standardising allergoid platforms.

Electronic supplementary material

The online version of this article (doi:10.1186/s40413-017-0146-3) contains supplementary material, which is available to authorized users.

Safety and efficacy of short-term oral immunotherapy with Cry j 1-galactomannan conjugate for Japanese cedar pollinosis: a randomized controlled trial

Current allergen-specific immunotherapy (AIT) for pollinosis requires long-term treatment with potentially severe side effects. Therefore, development of an AIT that is safe and more convenient with a shorter regimen is needed. This prospective, double-blind, placebo-controlled trial randomized 55 participants with Japanese cedar pollinosis (JCP) to active or placebo groups to test the safety and efficacy of short-term oral immunotherapy (OIT) with Cry j 1-galactomannan conjugate for JCP. Mean symptom-medication score as the primary outcome in the active group improved 27.8% relative to the placebo group during the entire pollen season. As the secondary outcomes, mean medication score in active group improved significantly, by 56.2%, compared with placebo during the entire pollen season. Mean total symptom score was similar between active and placebo groups during the entire pollen season. There were no severe treatment-emergent adverse events in the active and placebo groups. Therefore short-term OIT with Cry j 1-galactomannan conjugate is safe, and effective for reducing the amount of medication use for JCP.

[Immunological mechanisms of allergen-specific immunotherapy]

Allergen-specific immunotherapy is accompanied by multiple changes on the cellular and humoral level. A shift of Th2 immune responses towards immune responses of the Th1 type, which goes along with an increase of regulatory T cells and B cells, IL-10 as well as reduction of effector cells and eosinophils in the tissue, combined with lower IgE production in favor of higher IgG4 production, are regarded as key mechanisms of allergen-specific immunotherapy . A better understanding of immunologic pathways of specific immunotherapy would be essential for the improvement of this therapy as well as for the development of reliable biomarkers capable to monitor therapeutic responses as well as compliance of the patients.

European Survey on Adverse Systemic Reactions in Allergen Immunotherapy (EASSI): a real-life clinical assessment

BACKGROUND

Outside clinical trials, data on systemic reactions (SRs) due to allergen immunotherapy (AIT) are scarce.

METHODS

A prospective, longitudinal, web-based survey of 'real-life' respiratory allergen immunotherapy (AIT) clinical practice was conducted in France, Germany and Spain. SRs were recorded and coded according to the Medical Dictionary for Regulatory Activities (MedDRA) and risk factors associated with SRs were identified.

RESULTS

A total of 4316 patients (corresponding to 4363 ongoing courses of AIT) were included. A total of 109 SRs were recorded, and 90 patients (2.1%) presented at least one SR. Most of the SRs occurred in subcutaneous allergen immunotherapy (SCIT) (89%, n = 97). The most frequently reported symptoms were urticaria, rhinitis, dyspnoea and cough. Respiratory symptoms appeared before skin symptoms. Most SRs occurred during the up-dosing phase (75.8%) and were mild in severity (71.6%). Intramuscular adrenaline was administered in 17 SRs, but only 65% of these were subsequently classified as anaphylaxis. Independent risk factors for SRs during SCIT were as follows: the use of natural extracts (odds ratio, OR) [95% confidence interval (CI)] = 2.74 [1.61-4.87], P = 0.001), the absence of symptomatic allergy medications (1.707 [1.008-2.892], P = 0.047), asthma diagnosis (1.74 [1.05-2.88], P = 0.03), sensitization to animal dander (1.93 [1.21-3.09], P = 0.006) or pollen (1.16 [1.03-1.30], P = 0.012) and cluster regimens (vs rush) (4.18 [1.21-14.37], P = 0.023). A previous episode of anaphylaxis increased the risk for anaphylaxis in SCIT (OR [95% CI] = 17.35 [1.91-157.28], P = 0.01).

CONCLUSION

AIT for respiratory allergy is safe, with a low number of SRs observed in real-life clinical practice. A personalized analysis of risk factors could be used to minimize SRs.

Evaluation of a sublingual immunotherapy solution in olive-induced respiratory allergy in Jordan: a retrospective observational study

Background

Olive pollen is an important cause of respiratory allergy in the Middle East. In this study, the clinical characteristics of adults and children with confirmed allergic rhinitis (AR; with or without asthma) in Jordan were described, and the use of sublingual immunotherapy (SLIT) in a real-life clinical setting was assessed.

Methods

This retrospective observational study evaluated the clinical features of olive-induced allergy and the use of an SLIT solution of standardized extracts toward Ole e 1 given in a pre- and coseasonal scheme with a daily dose of 300 index of reactivity for two consecutive seasons. Inclusion criteria were as follows: ≥5 years of age, AR, proven olive sensitization, and at least 2 years follow-up after SLIT initiation. The following data were recorded at SLIT initiation: clinical characteristics, rhinitis and asthma symptom scores, and concomitant symptomatic medications. During follow-up and at the end of each season, the following data were recorded: symptom progression/scores, any changes to symptomatic medications, and treatment compliance. The secondary objective was to determine any effect on quality of life, use of concomitant AR medications, and treatment compliance.

Results

Eighty-six patients with seasonal AR were included in this analysis (52.3% with coexisting asthma). Between the initiation of treatment and the end of second pollen season, symptoms of AR and asthma were decreased by 79.5% and 41.7%, respectively, with an improvement in quality of life score in 71.5% of the patients (P<0.0001 for all). Physicians reported that after 2 years of SLIT, there was an improvement in the symptoms of both AR (95.2%) and asthma (93.3%), with 98.8% of the patients showing good treatment compliance. A reduction in symptomatic medications was also found. SLIT was well tolerated with no systemic reactions being reported.

Conclusion

In children and adults with olive-associated respiratory allergy in Jordan, the use of a pre- and coseasonal SLIT with a 300 index of reactivity daily dose is effective in reducing the clinical burden of AR and asthma with no tolerability issues.

Cost-effectiveness of SQ® HDM SLIT-tablet in addition to pharmacotherapy for the treatment of house dust mite allergic rhinitis in Germany

Background

Allergic rhinitis is a global health problem that burdens society due to associated health care costs and its impact on health. Standardized quality (SQ^®) house dust mite (HDM) sublingual immunotherapy (SLIT)-tablet is a sublingually administered allergy immunotherapy tablet for patients with persistent moderate to severe HDM allergic rhinitis despite use of allergy pharmacotherapy.

Objective

To assess the cost-effectiveness of SQ HDM SLIT-tablet in Germany for patients suffering from HDM allergic rhinitis.

Methods

A pharmacoeconomic analysis, based on data collected in a double-blinded, phase III randomized placebo-controlled trial (n=992), was undertaken to compare SQ HDM SLIT-tablet in addition to allergy pharmacotherapy to placebo plus allergy pharmacotherapy. Quality-adjusted life year (QALY) scores and health care resource use data recorded in the trial were applied to each treatment group and extrapolated over a nine-year time horizon. A series of scenarios were used to investigate the impact of changes on long-term patient health for both treatment groups, which was measured by annual changes in QALY scores. Deterministic and probabilistic sensitivity analyses were also performed.

Results

In the base case analysis, compared with allergy pharmacotherapy, SQ HDM SLIT-tablet led to a QALY gain of 0.31 at an incremental cost of €2,276 over the nine-year time horizon, equating to an incremental cost-effectiveness ratio of €7,519. The treatment was cost-effective for all scenarios analyzed; however, results were sensitive to changes in individual parameter values during the deterministic sensitivity analysis.

Conclusion

SQ HDM SLIT-tablet in addition to pharmacotherapy is cost-effective compared with allergy pharmacotherapy plus placebo for the treatment of persistent moderate to severe HDM allergic rhinitis that is not well controlled by allergy pharmacotherapy.

A review of clinical efficacy, safety, new developments and adherence to allergen-specific immunotherapy in patients with allergic rhinitis caused by allergy to ragweed pollen (Ambrosia artemisiifolia)

Allergic rhinitis is a common health problem in both children and adults. The number of patients allergic to ragweed (Ambrosia artemisiifolia) is on the rise throughout Europe, having a significant negative impact on the patients' and their family's quality of life. Allergen-specific immunotherapy (AIT) has disease-modifying effects and can induce immune tolerance to allergens. Both subcutaneous immunotherapy and sublingual immunotherapy with ragweed extracts/preparations have clear positive clinical efficacy, especially over pharmacological treatment, even years after the treatment has ended. AIT also has very good safety profiles with extremely rare side effects, and the extracts/preparations used in AIT are commonly well tolerated by patients. However, patient adherence to treatment with AIT seems to be quite low, mostly due to the fact that treatment with AIT is relatively time-demanding and, moreover, due to patients not receiving adequate information and education about the treatment before it starts. AIT is undergoing innovations and improvements in clinical efficacy, safety and patient adherence, especially with new approaches using new adjuvants, recombinant or modified allergens, synthetic peptides, novel routes of administration (epidermal or intralymphatic), and new protocols, which might make AIT more acceptable for a wider range of patients and novel indications. Patient education and support (eg, recall systems) is one of the most important goals for AIT in the future, to further enhance treatment success.

Clinical practice recommendations for allergen-specific immunotherapy in children: the Italian consensus report

Allergen-specific immunotherapy (AIT) is currently recognized as a clinically effective treatment for allergic diseases, with a unique disease-modifying effect. AIT was introduced in clinical practice one century ago, and performed in the early years with allergenic extracts of poor quality and definition. After the mechanism of allergic reaction were recognized, the practice of AIT was refined, leading to remarkable improvement in the efficacy and safety profile of the treatment. Currently AIT is accepted and routinely prescribed worldwide for respiratory allergies and hymenoptera venom allergy. Both the subcutaneous (SCIT) and sublingual (SLIT) routes of administration are used in the pediatric population.AIT is recommended in allergic rhinitis/conjunctivitis with/without allergic asthma, with an evidence of specific IgE-sensitization towards clinically relevant inhalant allergens. Long-term studies provided evidence that AIT can also prevent the onset of asthma and of new sensitizations. The favorable response to AIT is strictly linked to adherence to treatment, that lasts 3-5 years. Therefore, several factors should be carefully evaluated before starting this intervention, including the severity of symptoms, pharmacotherapy requirements and children and caregivers' preference and compliance.In recent years, there have been increasing interest in the role of AIT for the treatment of IgE-associated food allergy and extrinsic atopic dermatitis. A growing body of evidence shows that oral immunotherapy represents a promising treatment option for IgE-associated food allergy. On the contrary, there are still controversies on the effectiveness of AIT for patients with atopic dermatitis.This consensus document was promoted by the Italian Society of Pediatric Allergy and Immunology (SIAIP) to provide evidence-based recommendations on AIT in order to implement and optimize current prescription practices of this treatment for allergic children.

Effects of sublingual immunotherapy in a murine asthma model sensitized by intranasal administration of house dust mite extracts

BACKGROUND

Sublingual immunotherapy (SLIT) has received attention as a method for allergen immunotherapy. However, the mechanism of SLIT has not yet been fully investigated. Therefore, we evaluated the effects of SLIT in a murine asthma model, sensitized by intranasal administration of house dust mite (HDM) extracts.

METHODS

Female BALB/c mice were intranasally exposed to HDM for either 3 or 5 weeks (5 consecutive days per week). Mice were administered either low-dose (0.5 mg/day) or high-dose (5 mg/day) sublingual HDM extracts for 2 weeks, followed by an additional week of intranasal exposure. Airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cell count, cytokine levels in the BALF and lymph node cell culture supernatants, and allergen-specific antibodies were measured. Lung histology was also investigated.

RESULTS

In mice sensitized for 5 weeks, high-dose SLIT ameliorated AHR, airway eosinophilia and goblet cell metaplasia. In mice sensitized for 3 weeks, even low dose SLIT ameliorated AHR and airway eosinophilia. Th2 cytokine levels in culture supernatants of submandibular lymph node cells in high-dose SLIT mice decreased, whereas IL-10 levels increased. Total IgA in BALF increased in mice sensitized for 3 or 5 weeks, and high-dose SLIT also increased allergen-specific IgG2a in mice sensitized for 5 weeks.

CONCLUSIONS

These data suggest that earlier induction of SLIT in HDM-sensitized mice provides superior suppression of AHR and goblet cell metaplasia. The modulation of allergen specific IgG2a and local IgA might play a role in the amelioration of AHR and airway inflammation.

Subcutaneous and Sublingual Immunotherapy in Allergic Asthma in Children

This review presents up-to-date understanding of immunotherapy in the treatment of children with allergic asthma. The principal types of allergen immunotherapy (AIT) are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). Both of them are indicated for patients with allergic rhinitis and/or asthma, who have evidence of clinically relevant allergen-specific IgE, and significant symptoms despite reasonable avoidance measures and/or maximal medical therapy. Studies have shown a significant decrease in asthma symptom scores and in the use of rescue medication, and a preventive effect on asthma onset. Although the safety profile of SLIT appears to be better than SCIT, the results of some studies and meta-analyses suggest that the efficacy of SCIT is better and that SCIT has an earlier onset than SLIT in children with allergic asthma. Severe, not controlled asthma, and medical error were the most frequent causes of SCIT-induced adverse events.

Anti-Interleukin-9 Antibody Increases the Effect of Allergen-Specific Immunotherapy in Murine Allergic Rhinitis

Purpose

Interleukin (IL)-9 induces allergic responses; however, the roles of anti-IL-9 antibody in the induction of tolerance remain unclear. This study investigated the effects of anti-IL-9 antibody on oral tolerance (OT) in a mouse model of allergic rhinitis (AR).

Methods

BALB/c mice were divided into 4 groups: the control, AR, OT, and OT with anti-IL-9 antibody (OT+IL9AB) groups. Ovalbumin (OVA) was used for sensitization and challenge. Mice in the OT and OT+IL9AB groups were fed OVA for immunotherapy. During immunotherapy, OT+IL9AB mice were injected with anti-IL-9 antibody. Allergic symptoms, tissue eosinophil counts, and serum OVA-specific immunoglobulin E (IgE) were measured. The mRNA expressions of cytokines and transcription factors of T cells of nasal mucosa were determined by real-time polymerase chain reaction (PCR). The protein levels of GATA3, ROR-γt, and Foxp3 in nasal mucosa were determined by Western blot. CD4⁺CD25⁺Foxp3⁺ T cells in the spleen were analyzed by flow cytometry.

Results

Administration of anti-IL-9 antibody decreased allergic symptoms, OVA-specific IgE levels, and eosinophil counts. In addition, it inhibited T-helper (Th) 2 responses, but had no effect on Th1 responses. Protein levels of ROR-γt and mRNA levels of PU.1 and ROR-γt were reduced by anti-IL-9 antibody. Anti-IL-9 antibody increased Foxp3 and IL-10 mRNA expression, Foxp3 protein, and induction of CD4⁺CD25⁺Foxp3⁺ T cells.

Conclusions

Anti-IL-9 antibody decreased allergic inflammation through suppression of Th2 and Th17 cells. Anti-IL-9 antibody enhanced the tolerogenic effects of regulatory T cells. These results suggest that anti-IL-9 antibody might represent a potential therapeutic agent for allergen immunotherapy in patients with uncontrolled allergic airway disease.

Efficacy and Safety of Sublingual Immunotherapy for Allergic Rhinitis in Pediatric Patients: A Meta-Analysis of Randomized Controlled Trials

Background

Allergic rhinitis (AR) has become a global health problem that constantly affects a large part of the general population, especially children.

Objective

Sublingual allergen immunotherapy (SLIT) has been used extensively for pediatric AR, although its efficacy and safety are often questioned. In this meta-analysis of randomized controlled trials (RCT), we evaluated the use of SLIT for pediatric AR.

Methods

A number of medical literature data bases were searched through January 2016 to identify RCTs that examined the use of SLIT for pediatric AR and that assessed clinical outcomes related to efficacy. Descriptive and quantitative information was abstracted. Standardized mean differences (SMD) were calculated by using fixed- and random-effects models. Subgroup analyses were performed. Heterogeneity was assessed by using the I2 metric. A network meta-analysis was used to estimate SMDs between two SLIT protocols for pediatric seasonal AR. All data were extracted from publications or received from the authors.

Results

Twenty-six studies were eligible for inclusion in the meta-analysis of rhinitis or rhinoconjunctivitis symptom scores, and 19 studies were eligible for the meta-analysis of medication scores. Descriptive and quantitative data were extracted. SLIT differed significantly from placebo in terms of symptom scores (SMD -0.55 [95% confidence interval {CI}, -0.86 to -0.25]; p = 0.0003, I2 = 90%) and medication scores (SMD -0.67 [95% CI, -0.96 to -0.38J; p < 0.00001, I2 = 83%). Oral pruritus was the adverse effect, which occurred most commonly in children who were receiving SLIT. Network meta-analysis revealed no significant difference between the pre-coseasonal and continuous SLIT protocols for seasonal AR in symptom scores (SMD -6.55 [95% CI, -25.38 to 12.29]; p = 0.496) and medication scores (SMD -8.83 [95% CI, -22.10 to 4.43]; p = 0.192).

Conclusions

Our meta-analysis results indicated that SLIT provided significant symptom relief and reduced the need for medication in pediatric patients Moreover, the safety of SLIT needs to be confirmed in RCTs with larger samples.

Efficacy of Sublingual Immunotherapy for House Dust Mite-Induced Allergic Rhinitis: A Meta-Analysis of Randomized Controlled Trials

Purpose

Allergic rhinitis (AR) has become a global issue for a large part of the general population. Sublingual immunotherapy (SLIT) has been used extensively to treat persistent allergic rhinitis (PAR). Although systematic reviews have confirmed the effectiveness of SLIT for the treatment of AR, a considerable number of studies using extracts of house dust mites (HDMs) for immunotherapy found no consensus on basic treatment parameters and questioned the efficacy of SLIT.

Methods

In this study, we evaluated SLIT for PAR by a meta-analysis of randomized controlled trials (RCTs). Medline, Embase, and Cochrane Library database searches were performed for RCTs on the treatment of PAR by SLIT that assessed clinical outcomes related to efficacy through May 2016. Descriptive and quantitative information was abstracted. An analysis was performed with standardized mean differences (SMDs) under a fixed or random effects model. Subgroup analyses were performed. Heterogeneity was assessed using the I² metric.

Results

In total, 25 studies were eligible for inclusion in the meta-analysis for symptom scores and 15 studies for medication scores. SLIT was significantly different from the controls for symptom scores (SMD=1.23; 95% confidence interval [CI]=1.74 to 0.73; P<0.001). For medication scores, significant differences for SLIT were also observed versus the controls (SMD=-1.39; 95% CI=-1.90 to -0.88; P<0.001).

Conclusions

Our meta-analysis indicates that SLIT provided significant symptom relief and reduced the need for medications in PAR. In this study, significant evidence was obtained despite heterogeneity with regard to the use of mite extract. Specifically, the mite extract used was provided by the patients with PAR. Furthermore, to confirm both the objective outcomes and the effective doses of HDM allergen extracts, experimental data should be obtained from large high-quality population-based studies.

The Potential Role of Allergen Immunotherapy in Stepping Down Asthma Treatment

For patients whose asthma is controlled and who have a low risk for future exacerbations, current guidelines recommend gradually stepping down pharmacotherapy to identify the lowest dose needed to maintain control. This review article will discuss the benefits and risks of step down in asthma management and the different strategies of achieving step down with particular focus on allergen immunotherapy (AIT). A literature search was conducted to identify studies that assessed the effect of AIT on asthma step down and evaluated this and asthma control as one of the outcomes. Six studies were identified: 2 subcutaneous and 4 sublingual AIT studies. Five studies assessed house dust mite-induced asthma, whereas 1 study focused on birch-induced seasonal asthma. Regarding house dust mite-induced asthma, the AIT studies reviewed suggest that individuals with moderate rather than mild asthma are the patients who are more likely to benefit from the addition of AIT for their asthma condition. The potential value of AIT is likely to be in enabling successful step down of the inhaled corticosteroid dose in Global Initiative for Asthma step 3 or 4. It is important to further explore this effect so that affected individuals can benefit from this treatment.

The role of allergen immunotherapy in the management of allergic rhinitis

PURPOSE

To evaluate the role of allergen immunotherapy (AIT) in the treatment of allergic rhinitis (AR).

METHOD

Individual studies, systematic reviews, and practice guidelines that included information on sublingual AIT (SLIT) and subcutaneous AIT (SCIT) in the treatment of AR were considered.

RESULTS

AIT via the SLIT or SCIT route has been shown to be effective in treating AR symptoms with resultant improvements in overall quality of life, comorbid illnesses, and medication requirements. Persistent clinical benefits have been demonstrated years after AIT treatment discontinuation. AIT may prevent the progression of AR to asthma. In addition, studies that evaluated the pharmacoeconomics of AR treatment indicate that AIT may be more cost effective than pharmacotherapy. The AIT cost savings are likely underestimated in that few cost comparison studies considered AIT's long-term benefits or preventive effects.

CONCLUSION

Multiple individual studies and systematic reviews provide strong evidence for the clinical effectiveness of AIT in the treatment of AR. Cost-effectiveness and disease modification are additional advantages of AIT compared with standard drug treatment in the management of AR.

T-cell epitope-containing hypoallergenic β-lactoglobulin for oral immunotherapy in milk allergy

BACKGROUND

Optimally hydrolyzed β-Lactoglobulin (βLg) is a promising milk oral immunotherapy (OIT) candidate with respect to showing reduced B-cell reactivity but retaining the T-cell epitope. To demonstrate that an edible hypoallergenic βLg hydrolysate containing the T-cell epitope is suitable for OIT. We tested how chymotrypsin affected the retention of the T-cell epitope of βLg when preparing βLg hydrolysates using food-grade trypsin.

METHODS

We investigated the effect of chymotrypsin activity on the formation of the T-cell epitope-containing peptide of βLg (βLg_102-124 ) and prepared an edible βLg hydrolysate containing βLg_102-124 using screened food-grade trypsins. B-cell reactivity was determined using immunoassays in which ELISA was performed with anti-βLg rabbit IgG and Western blotting was performed with a milk-specific IgE antiserum.

RESULTS

In βLg hydrolysis performed by varying the activity of trypsin and chymotrypsin, chymotrypsin activity inhibited the formation of βLg_102-124 with an increase in hydrolysis time in a dose-dependent manner. βLg_102-124 was generated by two of five food-grade trypsins used at a ratio of 1:50 (w/w, enzyme/substrate) for 20 h at 40°C. The edible βLg hydrolysate retained βLg_102-124 and showed a reduction in molecular weight distribution and antigenicity against IgG and IgE.

CONCLUSIONS

Chymotrypsin activity inhibited the formation of βLg_102-124 in the trypsin hydrolysate of βLg. This βLg trypsin hydrolysate is a novel candidate for peptide-based OIT in cow's milk allergy for safely inducing desensitization.

Food allergy: immune mechanisms, diagnosis and immunotherapy

Food allergy is a pathological, potentially deadly, immune reaction triggered by normally innocuous food protein antigens. The prevalence of food allergies is rising and the standard of care is not optimal, consisting of food-allergen avoidance and treatment of allergen-induced systemic reactions with adrenaline. Thus, accurate diagnosis, prevention and treatment are pressing needs, research into which has been catalysed by technological advances that are enabling a mechanistic understanding of food allergy at the cellular and molecular levels. We discuss the diagnosis and treatment of IgE-mediated food allergy in the context of the immune mechanisms associated with healthy tolerance to common foods, the inflammatory response underlying most food allergies, and immunotherapy-induced desensitization. We highlight promising research advances, therapeutic innovations and the challenges that remain.

IgE and allergen-specific immunotherapy-induced IgG4 recognize similar epitopes of Bet v 1, the major allergen of birch pollen

BACKGROUND

Allergen-specific immunotherapy (AIT) with birch pollen generates Bet v 1-specific immunoglobulin (Ig)G₄ which blocks IgE-mediated hypersensitivity mechanisms. Whether IgG₄ specific for Bet v 1a competes with IgE for identical epitopes or whether novel epitope specificities of IgG₄ antibodies are developed is under debate.

OBJECTIVE

We sought to analyze the epitope specificities of IgE and IgG₄ antibodies from sera of patients who received AIT.

METHODS

15 sera of patients (13/15 received AIT) with Bet v 1a-specific IgE and IgG₄ were analyzed. The structural arrangements of recombinant (r)Bet v 1a and rBet v 1a_{_11x} , modified in five potential epitopes, were analyzed by circular dichroism and nuclear magnetic resonance spectroscopy. IgE binding to Bet v 1 was assessed by ELISA and mediator release assays. Competitive binding of monoclonal antibodies specific for Bet v 1a and serum IgE/IgG₄ to rBet v 1a and serum antibody binding to a non-allergenic Bet v 1-type model protein presenting an individual epitope for IgE was analyzed in ELISA and western blot.

RESULTS

rBet v 1a_{_11x} had a Bet v 1a - similar secondary and tertiary structure. Monomeric dispersion of rBet v 1a_{_11x} was concentration and buffer-dependent. Up to 1500-fold increase in the EC₅₀ for IgE-mediated mediator release induced by rBet v 1a_{_11x} was determined. The reduction of IgE and IgG₄ binding to rBet v 1a_{_11x} was comparable in 67% (10/15) of sera. Bet v 1a-specific monoclonal antibodies inhibited binding of serum IgE and IgG₄ to 66.1% and 64.9%, respectively. Serum IgE and IgG₄ bound specifically to an individual epitope presented by our model protein in 33% (5/15) of sera.

CONCLUSION AND CLINICAL RELEVANCE

Patients receiving AIT develop Bet v 1a-specific IgG₄ which competes with IgE for partly identical or largely overlapping epitopes. The similarities of epitopes for IgE and IgG₄ might stimulate the development of epitope-specific diagnostics and therapeutics.

Allergy immunotherapy across the life cycle to promote active and healthy ageing: from research to policies: An AIRWAYS Integrated Care Pathways (ICPs) programme item (Action Plan B3 of the European Innovation Partnership on active and healthy ageing) and the Global Alliance against Chronic Respiratory Diseases (GARD), a World Health Organization GARD research demonstration project

Allergic diseases often occur early in life and persist throughout life. This life-course perspective should be considered in allergen immunotherapy. In particular it is essential to understand whether this al treatment may be used in old age adults. The current paper was developed by a working group of AIRWAYS integrated care pathways for airways diseases, the model of chronic respiratory diseases of the European Innovation Partnership on active and healthy ageing (DG CONNECT and DG Santé). It considered (1) the political background, (2) the rationale for allergen immunotherapy across the life cycle, (3) the unmet needs for the treatment, in particular in preschool children and old age adults, (4) the strategic framework and the practical approach to synergize current initiatives in allergen immunotherapy, its mechanisms and the concept of active and healthy ageing.

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.

Different Responses in Induction of Allergen Specific Immunoglobulin G4 and IgE-Blocking Factors for Three Mite Subcutaneous Immunotherapy Products

PURPOSE

Specific immunoglobulin G4 (sIgG4) and immunoglobulin E (IgE)-blocking factors produced by subcutaneous immunotherapy (SCIT) play a critical role in the induction of allergen tolerance. However, comparative studies of available SCIT reagents on the induction of sIgG4 are limited. We compared increases in sIgG4 for three different house dust mite (HDM) SCIT reagents.

MATERIALS AND METHODS

Seventy-two HDM sensitized allergic patients were enrolled and classified into four groups: 1) control (n=27), 2) SCIT with Hollister-Stier® (n=19), 3) Tyrosine S® (n=16), and 4) Novo-Helisen® (n=10). Levels of specific IgE (sIgE), sIgG4, and IgE blocking factor to Dermatophagoides farinae (D. farinae) were measured using ImmunoCAP (sIgE, sIgG4) and enzyme-linked immunosorbent assay (ELISA) (IgE-blocking factors). Levels were measured before and 13.9±6.6 months after the SCIT. The allergen specificity and the induction levels of sIgE and sIgG4 were confirmed by immunoblot analysis.

RESULTS

After SCIT, sIgG4 levels to D. farinae increased significantly; however, the increases differed significantly among the SCIT groups (p<0.001). Specific IgG4 levels to D. farinae were highest in Hollister-Stier® (3.7±4.1 mg/L), followed by Novo-Helisen® (2.2±2.3 mg/L) and Tyrosine S® (0.7±0.5 mg/L). In addition, patients who were administered using Hollister-Stier® showed the most significant decrease in IgE/IgG4 ratio (p<0.001) and increase in blocking factor (p=0.009). Finally, according to IgE immunoblot results, the Hollister-Stier® group showed the most significant attenuation of IgE binding patterns among others.

CONCLUSION

Currently available SCIT reagents induce different levels of specific IgG4, IgE/IgG4 ratio, and IgE-blocking factor.

Applications and mechanisms of immunotherapy in allergic rhinitis and asthma

Clinical and immunologic tolerance are hallmarks of successful allergen immunotherapy (AIT). Clinical benefits such as reduced symptoms, pharmacotherapy intake and improvement of quality of life persist following cessation of treatment. Successful AIT is associated with suppression of allergic inflammatory cells such as mast cells, eosinophils and basophils in target organs. Furthermore, AIT down-regulates type 2 innate lymphoid cells and allergen-specific type 2 T-helper (Th2) cells. The immunologic tolerant state following AIT is associated with the induction of distinct phenotypes of regulatory T-cells (T-regs) including interleukin (IL)-10-, IL-35- and transforming growth factor (TGF)-β- producing T-regs and FoxP3⁺ T-regs. B-cell responses, including the induction of IL-10⁺ regulatory B-cells (B-regs) and the production of IgG4-associated blocking antibodies are also induced following successful AIT. These events are associated with the suppression of antigen-specific Th2 responses and delayed immune deviation in favour of Th1 type responses. Insight into the mechanisms of AIT has allowed identification of novel biomarkers with potential to predict the clinical response to AIT and also novel therapeutic strategies for more effective and safer AIT.

Cost utility analysis of the SQ(®) HDM SLIT-tablet in house dust mite allergic asthma patients in a German setting

BACKGROUND

Asthma affects an estimated 300 million people worldwide with the condition associated with significant healthcare utilisation costs and a large impact on patient quality of life. The SQ(®) HDM SLIT-tablet (ACARIZAX(®), Hørsholm, Denmark) is a sublingually administered allergy immunotherapy tablet for house dust mite allergic asthma and allergic rhinitis and has recently been licensed in Europe.

OBJECTIVE

To assess the cost-effectiveness of ACARIZAX plus pharmacotherapy versus placebo plus pharmacotherapy in patients with house dust mite allergic asthma that is uncontrolled by inhaled corticosteroids, in a German setting. Eligible patients should also have symptoms of mild to severe allergic rhinitis.

METHODS

A cost utility analysis was undertaken, based on the results of a European phase III randomised controlled trial, in which ACARIZAX was compared with placebo with both treatment groups also receiving pharmacotherapy in the form of inhaled corticosteroids and short-acting β2-agonists. Cost and quality-adjusted life years from the trial were extrapolated over a nine year time horizon and the incremental cost-effectiveness ratio calculated to compare treatment options.

RESULTS

ACARIZAX plus pharmacotherapy was estimated to generate 6.16 quality-adjusted life years per patient at a cost of €5658, compared with 5.50 quality-adjusted life years (QALYs) at a cost of €2985 for placebo plus pharmacotherapy. This equated to an incremental cost of €2673, incremental QALYs of 0.66 and an incremental cost-effectiveness ratio (ICER) of €4041. The ICER was, therefore, substantially lower than the €40,000 willingness-to-pay threshold per QALY adopted for the analysis. Deterministic sensitivity analyses indicate the results are most sensitive to the utility score of ACARIZAX patients during years 2 and 3 of treatment.

CONCLUSION

This analysis indicates that ACARIZAX plus pharmacotherapy is cost-effective compared with placebo plus pharmacotherapy for house dust mite allergic asthma patients in Germany. If a disease-modifying effect can be proven the results of this analysis may underestimate the true benefits of ACARIZAX.

Biomarkers for Allergen Immunotherapy: A "Panoromic" View

Biomarkers (BMKs) are biological parameters that can be measured to predict or monitor disease severity or treatment efficacy. The induction of regulatory dendritic cells (DCs) concomitantly with a downregulation of proallergic DC2s (ie, DCs supporting the differentiation of T-helper lymphocyte type 2 cells) in the blood of patients allergic to grass pollen has been correlated with the early onset of allergen immunotherapy efficacy. The combined use of omics technologies to compare biological samples from clinical responders and nonresponders is being implemented in the context of nonhypothesis-driven approaches. Such comprehensive "panoromic" strategies help identify completely novel candidate BMKs, to be subsequently validated as companion diagnostics in large-scale clinical trials.

CAR-modified T-cell therapy for cancer: an updated review

The use of chimeric antigen receptor (CAR)-modified T cells is a promising approach for cancer immunotherapy. These genetically modified receptors contain an antigen-binding moiety, a hinge region, a transmembrane domain, and an intracellular costimulatory domain resulting in T-cell activation subsequent to antigen binding. Optimal tumor removal through CAR-modified T cells requires suitable target antigen selection, co-stimulatory signaling domain, and the ability of CAR T cells to traffic, persist, and retain antitumor function after adoptive transfer. There are several elements which can improve antitumor function of CAR T cells, including signaling, conditioning chemotherapy and irradiation, tumor burden of the disease, T-cell phenotype, and supplementary cytokine usage. This review outlines four generations of CAR. The pre-clinical and clinical studies showed that this technique has a great potential for treatment of solid and hematological malignancies. The main purpose of the current review is to focus on the pre-clinical and clinical developments of CAR-based immunotherapy.

Patient engagement and patient support programs in allergy immunotherapy: a call to action for improving long-term adherence

Allergy immunotherapy (AIT) is acknowledged to produce beneficial mid- and long-term clinical and immunologic effects and increased quality of life in patients with allergic respiratory diseases (such as allergic rhinoconjunctivitis and allergic asthma). However, poor adherence to AIT (due to intentional and/or non-intentional factors) is still a barrier to achieving these benefits. There is an urgent need for patient support programs (PSPs) that encompass communication, educational and motivational components. In the field of AIT, a PSP should be capable of (1) improving adherence, (2) boosting patient engagement, (3) explaining how AIT differs from pharmacological allergy treatments; (4) increasing health literacy about chronic, progressive, immunoglobulin-E-mediated immune diseases, (5) helping the patient to understand and manage local or systemic adverse events, and (6) providing and/or predicting local data on aeroallergen levels. We reviewed the literature in this field and have identified a number of practical issues to be addressed when implementing a PSP for AIT: the measurement of adherence, the choice of technologies, reminders, communication channels and content, the use of "push" messaging and social networks, interactivity, and the involvement of caregivers and patient leaders. A key issue is "hi-tech" (i.e. approaches based mainly on information technology) vs. "hi-touch" (based mainly on interaction with humans, i.e. family members, patient mentors and healthcare professionals). We conclude that multistakeholder PSPs (combining patient-, provider and society-based actions) must now be developed and tested with a view to increasing adherence, efficacy and safety in the field of AIT.

Allergen-specific immunotherapy in pediatric allergic asthma

Allergen-specific immunotherapy (AIT) is the only curative way that can change the immunologic response to allergens and thus can modify the natural progression of allergic diseases. There are some important criteria which contributes significantly on efficacy of AIT, such as the allergen extract used for treatment, the dose and protocol, patient selection in addition to the severity and control of asthma. The initiation of AIT in allergic asthma should be considered in intermittent, mild and moderate cases which coexisting with other allergic diseases such as allergic rhinitis, and in case of unacceptable adverse effects of medications. Two important impact of AIT; steroid sparing effect and preventing from progression to asthma should be taken into account in pediatric asthma when making a decision on starting of AIT. Uncontrolled asthma remains a significant risk factor for adverse events and asthma should be controlled both before and during administration of AIT. The evidence concerning the efficacy of subcutaneous (SCIT) and sublingual immunotherapy (SLIT) for treatment of pediatric asthma suggested that SCIT decreases asthma symptoms and medication scores, whereas SLIT can ameliorate asthma symptoms. Although the effectiveness of SCIT has been shown for both seasonal and perennial allergens, the data for SLIT is less convincing for perennial allergies in pediatric asthma.

Immunologic alterations and efficacy of subcutaneous immunotherapy with Dermatophagoides pteronyssinus in monosensitized and polysensitized patients

BACKGROUND

There is a continuing debate about whether monoallergen subcutaneous immunotherapy (SCIT) is able to modulate immune and clinical responses toward main causal allergen in polysensitized patients.

OBJECTIVE

To investigate short-term immunologic changes and clinical effectiveness of SCIT with Dermatophagoides pteronyssinus in monosensitized and polysensitized patients who have rhinitis with or without asthma.

METHODS

Nineteen monosensitized and 24 polysensitized patients participated in this prospective, self-placebo-controlled, interventional study. Cluster immunotherapy with D pteronyssinus was administered after 2 months of placebo in both groups. Immunologic parameters, including CD203c expression on basophils after allergen stimulation, total IgE, specific IgE, and specific IgG4, were evaluated at baseline, after placebo, and after immunotherapy. Clinical effectiveness was assessed using monthly symptom-medication scores, visual analog scale, quality-of-life questionnaire, and nasal allergen provocation test.

RESULTS

At baseline, polysensitized patients had higher CD203c expression on basophils than monosensitized patients (P = .007). Activated basophils expressing CD203c, total IgE, and specific IgG4 were significantly increased after immunotherapy compared with baseline and placebo in the polysensitized group (P < .025). After immunotherapy, specific IgE and D pteronyssinus-induced CD203c expression were significantly higher in polysensitized than monosensitized patients (P < .05). The total symptom scores and the Mini Rhinoconjunctivitis Quality of Life Questionnaire scores in polysensitized patients and the visual analog scale scores in both groups were lower after immunotherapy compared with baseline and placebo (P < .025). Titrated nasal allergen provocation test with D pteronyssinus increased after immunotherapy in the monosensitized group (P < .05).

CONCLUSION

This study indicates that monosensitized and polysensitized patients have distinct humoral response and basophil behavior to SCIT. However, a single-allergen immunotherapy corresponding to the most clinically troublesome allergy in polysensitized patients can lead to early clinical efficacy comparable to that seen in monosensitized patients.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01795846.

Efficacy and safety of SQ house dust mite (HDM) SLIT-tablet treatment of HDM allergic asthma

INTRODUCTION

In the treatment of house dust mite (HDM) respiratory allergic disease, allergy immunotherapy constitutes an add-on treatment option targeting the underlying immunological mechanisms of allergic disease. However, for the treatment of HDM allergic asthma, the use of subcutaneous allergy immunotherapy (SCIT) has been limited by the risk of systemic adverse events. Thus, sublingually administered allergy immunotherapy (SLIT) has been investigated as a treatment option with an improved tolerability profile that allows for safer treatment of patients with HDM allergic asthma.

AREAS COVERED

In this Drug Profile, we provide a review of the clinical data behind the SQ HDM SLIT-tablet, which was recently approved for the treatment of HDM allergic asthma and allergic rhinitis by regulatory authorities in several European countries. Expert commentary: The SQ HDM SLIT-tablet is the first allergy immunotherapy to be tested prospectively in patients with asthma, and to favorably modify patient relevant end points such as requirement for inhaled corticosteroid (ICS) or the time to first asthma exacerbation upon ICS reduction, suggesting that SQ HDM SLIT-tablet treatment may contribute to improving overall asthma control.

International Consensus on Allergen Immunotherapy II: Mechanisms, standardization, and pharmacoeconomics

This article continues the comprehensive international consensus (ICON) statement on allergen immunotherapy (AIT). The initial article also recently appeared in the Journal. The conclusions below focus on key mechanisms of AIT-triggered tolerance, requirements in allergen standardization, AIT cost-effectiveness, and regulatory guidance. Potential barriers to and facilitators of the use of AIT are described in addition to future directions. International allergy specialists representing the European Academy of Allergy and Clinical Immunology; the American Academy of Allergy, Asthma & Immunology; the American College of Allergy, Asthma and Immunology; and the World Allergy Organization critically reviewed the existing literature and prepared this summary of recommendations for best AIT practice. The authors contributed equally and reached consensus on the statements presented herein.

Systemic Reactions to Dust Mite Subcutaneous Immunotherapy: A 3-Year Follow-up Study

Purpose

The incidence of allergen specific immunotherapy-related systemic reactions (SRs) varies among different studies, and many factors are likely to contribute to SRs. This study aims to investigate the incidence, characteristics, and risk factors of SRs to standardize dust mite-specific subcutaneous immunotherapy (SCIT) in Central China.

Methods

All patients receiving standardized dust mites (100-100,000 SQ-U/mL; Alutard SQ, Hørsholn, Denmark) immunotherapy were followed up. Recorded data included demographics, diagnosis, patient status, pulmonary function testing results before and after each injection, allergen dosage, and details of SRs.

Results

From June 2011 to August 2014, a total of 208 patients received 4,369 injections; 27 (13.0%) patients experienced 48 (1.1%) systemic reactions. Most of the SRs were grade 2 reactions (n=30, 62.5%), followed by grade 1 (n=11, 22.9%), grade 3 (n=7, 14.6%), and no fatal reactions occurred. Forty-six SRs (95.8%) occurred within 30 minutes. Higher SR rates were associated with high concentration extracts (100,000 SQ-U/mL), injections with concomitant local reactions (LRs), children, asthma and high sensitivity (skin prick test 3+/4+ and/or sIgE≥17.5 kUA/L) (P<0.05). The estimated odds of SRs increased in children (OR=6.57; 95% CI: 1.88-22.97, P=0.003), asthmatic patients (OR=4.10; 95% CI: 1.72-9.80, P=0.002), and injections with LRs (OR=2.41; 95% CI: 1.33-4.36, P=0.004).

Conclusions

The incidence of SRs to dust mite SCIT was low, and multiple factors were associated with the increased incidence of SRs. Children, asthmatics and patients with concomitant LR may be prone to develop SRs.

Novel strategies for the treatment of grass pollen-induced allergic rhinitis

INTRODUCTION

Allergic rhinitis (AR) affects over 20% of the population of Europe and the United States. Allergen immunotherapy (AIT) is currently the only form of treatment that affects symptoms and modifies the progression of disease. Established forms of AIT include subcutaneous (SCIT) and sublingual (SLIT) immunotherapy and are widely effective, yet only 2-9% of eligible patients undergo therapy, likely due to the long duration of treatment. As a result, novel, faster forms of AIT are currently under development.

AREAS COVERED

This article provides an overview of AR and summarises the efficacy and mechanisms of established forms of AIT, highlighting the current drawbacks. We discuss novel strategies of AIT that have been developed in an attempt to tackle these limitations, including epicutaneous, intradermal and intralymphatic immunotherapy (ILIT), focusing on ILIT, the treatment that has been most comprehensively assessed.

EXPERT OPINION

Current strategies to treat AR suffer from a poor safety profile and, importantly, lack of adherence. ILIT is a faster and safer form of AIT, with a treatment regime of only 12 weeks. Further validation is required, but ILIT, with its short and comparatively inexpensive protocol, has the potential to offer disease-modifying therapy to a larger number of patients.

Intralymphatic immunotherapy induces allergen specific plasmablasts and increases tolerance to skin prick testing in a pilot study

Background

Allergen Immunotherapy is a promising treatment of allergy. Seven patients with rhinoconjunctivitis to grass allergen were treated with intralymphatic immunotherapy (ILIT) to explore whether this treatment could be performed. Effect of treatment was assessed as change in symptom medication score, response in skin prick test and nasal allergen provocation. ILIT deposits allergen in an inguinal lymph node to elicit a strong immune stimulus. This allowed us to monitor appearance of allergen specific plasmablasts 7 days after allergen injection.

Findings

In an open trial of seven patients with a history of symptomatic allergic rhinoconjunctivitis due to grass pollen, three injections of allergen into inguinal lymph nodes were performed with monthly intervals. Allergen injections induced grass allergen specific plasmablasts expressing other isotypes than IgE after 7 days, induced a trend toward improvement in symptom and medication score and rhinoconjunctivitis-related quality of life during the grass pollen season 2013 and significantly raised the threshold in nasal allergen challenge and titrated skin prick testing. Mild side-effects were recorded after 3 of the 21 of injections (14 %).

Conclusions

This pilot study shows that ILIT may induce allergen specific plasmablasts, and confirms an effect on provocation of mast cells in skin and nasal mucosa during the ensuing winter.

Specific immunotherapy for rhinitis and asthma with a subcutaneous hypoallergenic high-dose house dust mite extract: results of a 9-month therapy

AIM

Effectiveness of a 9-month specific immunotherapy with a subcutaneous hypoallergenic high-dose house dust mite extract to reduce allergic symptoms as perceived by patients and physicians was assessed.

PATIENTS & METHODS

An observational, retrospective, multicenter study was carried out in patients diagnosed with asthma and/or rhinitis caused by house dust mites having started specific immunotherapy with Acaroid(®). Primary end point was perceived effectiveness.

RESULTS

A total of 409 patients were included. According to physician-completed visual analogue scale, a 58.1% clinical improvement was observed. Patient-completed visual analogue scale showed a 69.8% clinical improvement. The need for unscheduled/emergency healthcare, as an indication of poor quality of life, showed a significant reduction.

CONCLUSION

Our results confirm in a real-world setting the findings from randomized clinical trials of high-dose house dust mites allergoid immunotherapy with a subcutaneous hypoallergenic high-dose house dust mite extract.

Induction of Bronchial Tolerance After 1 Cycle of Monophosphoryl-A-Adjuvanted Specific Immunotherapy in Children With Grass Pollen Allergies

PURPOSE

Subcutaneous allergen-specific immunotherapy (SCIT) is a well-established and clinically effective method to treat allergic diseases, such as rhinitis and asthma. It remains unclear how soon after initiation of an ultra-short course of grass pollen immunotherapy adjuvanted with monophosphoryl lipid A (MPL)-specific bronchial tolerance can be induced.

METHODS

In a prospective study of 69 children double-sensitized to birch and grass pollens (51 males, average age 11.1 years), development of bronchial tolerance after 1 cycle of SCIT for grass was evaluated. In all the patients, the bronchial allergen provocation test (BAP) was performed before and after treatment. According to the results of the first BAP, the patients were divided into 2 groups: those showing a negative BAP with a decrease in FEV1 of <20% (seasonal allergic rhinitis [SAR] group, n=47); and those showing a positive BAP with a decrease in FEV1 of ≥20% (SAR with allergic asthma [SAR and Asthma] group, n=22). All the patients received MPL-adjuvanted, ultra-short course immunotherapy for birch, but only those with a positive BAP to grass received MPL-SCIT for grass.

RESULTS

After the pollen season, the BAP in the SAR group remained unchanged, while it was improved in the SAR and Asthma group (decrease in FEV1 of 28.8% vs 12.5%, P<0.01). The IgG4 levels increased after SCIT (median before SCIT 0.34 to 11.4 after SCIT), whereas the total and specific IgE levels remained unchanged.

CONCLUSIONS

After 1 cycle of MPL-SCIT, specific bronchial tolerance may be significantly induced, whereas in patients without SCIT, bronchial hyperactivity may remain unchanged.

Autologous Immunoglobulin Therapy in Patients With Severe Recalcitrant Atopic Dermatitis: Long-Term Changes of Clinical Severity and Laboratory Parameters

This report evaluated long-term changes in clinical severity and laboratory parameters in 3 adult patients with severe recalcitrant atopic dermatitis (AD) who were treated with intramuscular injections of 50 mg of autologous immunoglobulin G (IgG) twice a week for 4 weeks (autologous immunoglobulin therapy, AIGT) and followed up for more than 2 years after the treatment. We observed the following 4 major findings in these 3 patients during the long-term follow-up after AIGT. (1) Two of the 3 patients showed a long-term clinical improvement for more than 36 weeks after AIGT with a maximum decrease in clinical severity score greater than 80% from baseline. (2) These 2 patients also showed long-term decreases in serum total IgE concentrations and peripheral blood eosinophil count for more than 36 weeks after AIGT with a maximum decrease in the two laboratory parameters of allergic inflammatory greater than 70% from baseline. (3) No significant side effect was observed during the 2 years of follow-up period after the AIGT in all 3 patients. (4) Serum levels of IgG anti-idiotype antibodies to the F(ab')₂ fragment of autologous IgG administered for the treatment were not significantly changed after AIGT in all 3 patients. These findings suggest that AIGT has long-term favorable effects on both clinical severity and laboratory parameters in selected patients with severe recalcitrant AD. Further studies are required to evaluate the clinical usefulness and therapeutic mechanism of AIGT for AD.

Advances in patent applications related to allergen immunotherapy

INTRODUCTION

Allergies are among the most prevalent chronic diseases worldwide. Allergen-specific immunotherapy is used as an alternative treatment to pharmacotherapy. These immunotherapies are performed with crude extracts, which have disadvantages when compared to the new approaches, among them are recombinant proteins and hypoallergens. This review aims to assess immunotherapy for allergies through patent application analysis spanning recent decades.

AREAS COVERED

Patents referring to allergen immunotherapies used in allergy treatment. Data were obtained from the Espacenet® website, using the Cooperative Patent Classification (CPC) system. Two-hundred-and-one patent applications were analyzed, taking into consideration their classification by the type of technology and applicant.

EXPERT OPINION

Allergen-specific immunotherapy represents the only potentially curative therapeutic intervention for the treatment of allergic diseases. The extract-based immunotherapy is being replaced by the use of recombinant allergens, highlighting the hypoallergenic forms, which have low IgE-binding while retaining T-cell reactivity. It is expected that the development of hypoallergens will expand the scope of allergen-specific immunotherapy, especially if associated with alternative systems for expression and delivery systems with future potential. Furthermore, these new developments will likely address the problem of long-term protocols in allergen-specific immunotherapy, thus allowing better patient adherence and compliance.