Oral immunotherapy with low allergenic hydrolysed egg in egg allergic children

Online PGC-LC-MS analysis of colonic mucin O-glycans in ovalbumin-induced food allergy in Balb/c mice by treatment with sea cucumber chondroitin sulfate polysaccharide

The highly sulfated polysaccharide sea cucumber chondroitin sulfate (SCCS) can alleviate intestinal damage and display strong anti-food-allergic activity. The O-glycopattern levels in colonic mucin are closely related to the its protective effect on function of the intestinal barrier. However, the effect of the SCCS on colonic mucin O-glycan has not been investigated. In this study, ovalbumin (OVA)-sensitized allergic mice and SCCS treatment were used. Mouse colonic mucin O-glycome was released and analyzed through reductive β-elimination combined with PGC-LC-MS. A total of presumptive 20 neutral and 28 acidic O-glycan structures were identified, in which the core 2 type acidic O-glycan structure is predominant in Balb/c female mice. Treatment with OVA and SCCS did not change the numbers of colon mucin O-glycan type, but the expression level of total O-glycosylation was more abundant in the SCCS group mice than in the OVA group (1.8-fold), especially for acidic O-glycans (co-modified by fucose and sulfate groups). Furthermore, supplementation with SCCS reversed most of the O-glycan decreasing trend, which may be associated with a return to healthy levels of gut microbiota. In conclusion, our results demonstrate that SCCS could restore colonic mucin O-glycosylation levels and intestinal homeostasis and contribute to enhancing intestinal barrier function.

Cost-Effectiveness of Oral Immunotherapy for Egg Allergy According to Age of Therapy Commencement

BACKGROUND

Egg oral immunotherapy (OIT) can induce desensitization or remission of egg allergy in children.

OBJECTIVE

To determine the cost-effectiveness of OIT for raw egg allergy in school-age children compared with egg avoidance, and the most cost-effective age at which to commence treatment.

METHODS

A decision-analytic Markov model estimated the health and cost outcomes of 1,000 children aged 4 years with egg allergy, comparing different ages of OIT commencement (ages 4-12, inclusive) versus ongoing egg avoidance. Years lived with egg allergy, egg tolerance or remission (natural and OIT-induced), and desensitization to egg were captured, with rates of allergic reactions and utility values assigned to each health state. Treatment effects were derived from published randomized clinical trials and meta-analyses. The main outcome was the incremental cost-effectiveness ratio (ICER) from the Australian health care payer perspective (costs in Australian dollars per quality-adjusted life-year [QALY] gained), with a 20-year time horizon, 5% annual discounting, and an AU $50,000/QALY willingness-to-pay (WTP) threshold.

RESULTS

Without OIT, 858 children attained natural resolution before age 24. Under conservative assumptions, with OIT-induced remission set at zero and 84% achieving desensitization, ICERs were below the WTP threshold for treatment commencement at age 8 or older, with the smallest ICER observed at age 12 (AU $43,233/QALY; 95% CI, 32,025-73,350). However, the cost-effectiveness of OIT was achieved at all ages (ICER less than the WTP threshold) when OIT-induced remission increased to ∼40% of treated children.

CONCLUSIONS

Based on current published evidence, the cost-effectiveness of egg OIT improves with increased age of treatment commencement. Cost-effectiveness increases when the proportion of children achieving OIT-induced remission increases.

EAACI guidelines on the management of IgE-mediated food allergy

This European Academy of Allergy and Clinical Immunology (EAACI) guideline provides recommendations for the management of IgE-mediated food allergy and was developed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Following the confirmation of IgE-mediated food allergy diagnosis, allergen avoidance and dietary advice (with support of a specialised dietitian, if possible) together with the provision of a written treatment plan, education on the recognition of allergic symptoms and prescription of medication including adrenaline using an auto-injector are essential. Patients with significant anxiety and requirement for coping strategies may benefit from support from a clinical psychologist. As immunomodulatory interventions, omalizumab is suggested for treatment of IgE-mediated food allergy in children from the age of 1 and adults; and oral allergen-specific immunotherapy is recommended for children and adolescents with peanut allergy and suggested for milk and egg allergies (generally after 4 years of age for milk and egg). Sublingual and epicutaneous immunotherapy are suggested for peanut allergy but are not yet available at the point of care. Future research into disease modifying treatments for IgE-mediated food allergy are highly needed, with standardised and patient-focused protocols and outcomes.

Oral food immunotherapy in patients with atopic dermatitis

Atopic dermatitis (AD) is one of the main risk factors for infants in the development of food allergy. Oral immunotherapy (OIT) in early childhood has been found to be highly effective and safe in preschoolers with and without AD, especially in young infants. Delays in initiation of OIT in infants and children due to uncontrolled AD risk expansion of the number of foods children develop allergy to through unnecessary avoidance of multiple foods. Parents and caregivers may attribute eczema flares to OIT doses, which physicians usually ascribe to non-food triggers such as weather changes, psychological stress, and infection. There is a lack of published literature confirming OIT as a trigger of AD flares, and the degree to which OIT may be associated with AD flares needs to be further studied. We describe 8 case scenarios with varying degrees of AD flare before and during OIT. We propose management algorithms for children with preexisting concurrent AD and food allergy who are being considered for starting OIT and children with AD flares during OIT. Optimizing AD control strategies and providing adequate AD care education before starting OIT can reduce confusion for both parents and allergists if rashes arise during OIT, thus improving adherence to OIT.

Immunotherapy and biologics in the management of IgE-mediated food allergy: Systematic review and meta-analyses of efficacy and safety

Food allergy (FA) is a potentially life-threatening chronic condition that is becoming an increasing public health problem worldwide. This systematic review (SR) was carried out to inform the development of clinical recommendations on the treatment of IgE-mediated FA with biologics and/or IT for the update of the EAACI guidelines. A SR of randomized-controlled trials or quasi-controlled trials was carried out. Studies were identified via comprehensive search strategies in Medline, Embase, and Cochrane Library, up to April 2022.

POPULATION

Human adults, children, and adolescents with IgE-mediated FA.

INTERVENTION

IT and/or biologics.

COMPARATOR

Placebo or standard-of-care (allergen avoidance).

OUTCOME

Efficacy (desensitization, sustained unresponsiveness (SU), remission), quality of life, and safety (systemic and local adverse reactions (AR)). The Cochrane RoB tool was used to assess the risk of bias. It was reported according to PRISMA and registered in PROSPERO CRD4202229828. After screening, 121 studies were included (111 for IT and 10 for biologics). Most studies had a high risk of bias and showed high heterogeneity in design and results. Metanalysis showed a positive effect of biologics and IT in terms of relative risk (RR) for achieving tolerance to the culprit food compared to avoidance or placebo. Omalizumab for any FA showed a RR of 2.17 [95% confidence interval: 1.22, 3.85]. For peanut allergy, oral IT (OIT) had a RR of 11.94 [1.76, 80.84] versus avoidance or placebo, sublingual IT (SLIT) had a RR of 3.00 [1.04, 8.66], and epicutaneous IT (EPIT) of 2.16 [1.56, 3.00]. OIT had a RR of 5.88 [2.27, 15.18] for cow's milk allergy, and of 3.43 [2.24, 5.27] for egg allergy. There was insufficient data on SLIT or EPIT for the treatment of egg and milk allergies. Most ARs reported were mild. For OIT the most common AR involved the gastrointestinal system and for EPIT, AR's most commonly affected the skin. There was limited data on severe or life-threatening ARs. There was limited evidence for long term efficacy and quality of life. In conclusion, biologics and IT, alone or in combination, are effective in achieving desensitization while on active treatment but more evidence is needed on long-term tolerance as current evidence is not of high quality. Adverse events while on therapy are generally mild to moderate but a long-term comprehensive safety profile is missing. There is a critical need to optimize and standardize desensitization protocols and outcome measures to facilitate our understanding of the efficacy and safety as well as to allow for comparison between interventions.

Oral Immunotherapy: An Overview

Oral immunotherapy (OIT) is an alternative treatment of IgE-mediated food allergy that has been shown to increase tolerance threshold to many of the top food allergens, although this effect may be dependent on age, dose, frequency, and duration. OIT has been shown to be effective and safe in infants, and early initiation can improve rates of desensitization even for those foods whose natural history favors loss of allergy. Studies looking at protocol modification to improve OIT success are ongoing as is the evaluation of clinical tools to help monitor OIT effects.

Evaluation of clinical outcomes of efficacy in food allergen immunotherapy trials, COFAITH EAACI task force

Food allergy is a global public health problem that until recent years lacked any aetiological treatment supported by academy, industry and regulators. Food immunotherapy (AIT) is an evolving treatment option, supported by clinical practice and industry trial data. Recent AIT meta-analyses have highlighted the difficulty in pooling safety and efficacy data from AIT trials, due to secondary heterogeneity in the study. An EAACI task force (CO-FAITH) initiated by the Paediatric Section was created to focus on AIT efficacy outcomes for milk, egg and peanut allergy rather than in trial results. A systematic search and a narrative review of AIT controlled clinical trials and large case series was conducted. A total of 63 manuscripts met inclusion criteria, corresponding to 23, 21 and 22 studies of milk, egg and peanut AIT, respectively. The most common AIT efficacy outcome was desensitization, mostly defined as tolerating a maintenance phase dose, or reaching a particular dose upon successful exit oral food challenge (OFC). However, a large degree of heterogeneity was identified regarding the dose quantity defining this outcome. Sustained unresponsiveness and patient-reported outcomes (e.g. quality of life) were explored less frequently, and to date have been most rigorously described for peanut AIT versus other allergens. Change in allergen threshold assessed by OFC remains the most common efficacy measure, but OFC methods suffer from heterogeneity and methodological disparity. This review has identified multiple heterogeneous outcomes related to measuring the efficacy of AIT. Efforts to better standardize and harmonize which outcomes, and how to measure them must be carried out to help in the clinical development of safe and efficacious food allergy treatments.

Low-dose oral immunotherapy in immunoglobulin E-mediated food allergies

Nowadays, the management of food allergies has increasingly moved from conventional oral immunotherapy (OIT) to low-dose OIT or low-dose OIT utilizing hypoallergenic foods. This shift is largely because the latter appears to induce oral tolerance with fewer adverse effects than the former. However, the mechanisms underpinning such differences remain unclear. To better understand these mechanisms, we conducted a comparative study scrutinizing the mechanisms of OIT, especially those of low-dose desensitization. We also summarized articles on low-dose OIT and low-dose OIT using hypoallergenic foods. We examined the efficacy, safety, and immunological parameters of low-dose OIT and those of low-dose OIT with hypoallergenic foods with the aim of shedding some light on low-dose OIT and its therapeutic application in inducing oral tolerance for individuals with food allergies.

Clinical outcome and component-specific antibody levels in egg allergic children after lightened oral immunotherapy

OBJECTIVE

To evaluate the clinical outcome of lightened version of egg oral immunotherapy (OIT) and to analyze egg allergen component-specific antibody levels during short up-dosing with egg white powder and maintenance by egg in daily diet.

PATIENTS AND METHODS

Eighteen egg-allergic children received egg powder with short up--dosing and they maintained tolerance using egg in daily diet. Seventeen egg-allergic children served as a control group. Component-resolved analysis of serum immunoglobulin E (IgE), IgA1, IgA2, and IgG4 levels were determined at inclusion, after up-dosing and after 1 year of immunotherapy. Skin-prick tests were performed at inclusion and after 1 year of therapy.

RESULTS

All 18 patients in the egg OIT group were successfully desensitized. Desensitization was achieved on average in 4.5 months. In the control group, only two children tolerated egg in oral food challenge after 1 year. Of the measured immune markers, smaller wheal diameters in skin-prick testing, reduction in component-specific IgE levels, and increase in component-specific IgA1, IgA2, and IgG4 levels were associated with desensitization.

CONCLUSION

A lightened egg OIT is effective and safe in children with egg allergy. Increase in all egg component-specific IgA1, IgA2 and IgG4 levels and decrease in all egg component--specific IgE levels were observed after 12 months of OIT.

Tolerance to heated egg in egg allergy: Explanations and implications for prevention and treatment

Hen's egg allergy is the second most frequent food allergy found in children. Allergic symptoms can be caused by raw or heated egg, but a majority of egg-allergic children can tolerate hard-boiled or baked egg. Understanding the reasons for the tolerance towards heated egg provides clues about the molecular mechanisms involved in egg allergy, and the differential allergenicity of heated and baked egg might be exploited to prevent or treat egg allergy. In this review, we therefore discuss (i) why some patients are able to tolerate heated egg; by highlighting the structural changes of egg white (EW) proteins upon heating and their impact on immunoreactivity, as well as patient characteristics, and (ii) to what extent heated or baked EW might be useful for primary prevention strategies or oral immunotherapy. We describe that the level of immunoreactivity towards EW helps to discriminate patients tolerant or reactive to heated or baked egg. Furthermore, the use of heated or baked egg seems effective in primary prevention strategies and might limit adverse reactions. Oral immunotherapy is a promising treatment strategy, but it can sometimes cause significant adverse events. The use of heated or baked egg might limit these, but current literature is insufficient to conclude about its efficacy.

EAACI Molecular Allergology User's Guide 2.0

Since the discovery of immunoglobulin E (IgE) as a mediator of allergic diseases in 1967, our knowledge about the immunological mechanisms of IgE-mediated allergies has remarkably increased. In addition to understanding the immune response and clinical symptoms, allergy diagnosis and management depend strongly on the precise identification of the elicitors of the IgE-mediated allergic reaction. In the past four decades, innovations in bioscience and technology have facilitated the identification and production of well-defined, highly pure molecules for component-resolved diagnosis (CRD), allowing a personalized diagnosis and management of the allergic disease for individual patients. The first edition of the "EAACI Molecular Allergology User's Guide" (MAUG) in 2016 rapidly became a key reference for clinicians, scientists, and interested readers with a background in allergology, immunology, biology, and medicine. Nevertheless, the field of molecular allergology is moving fast, and after 6 years, a new EAACI Taskforce was established to provide an updated document. The Molecular Allergology User's Guide 2.0 summarizes state-of-the-art information on allergen molecules, their clinical relevance, and their application in diagnostic algorithms for clinical practice. It is designed for both, clinicians and scientists, guiding health care professionals through the overwhelming list of different allergen molecules available for testing. Further, it provides diagnostic algorithms on the clinical relevance of allergenic molecules and gives an overview of their biology, the basic mechanisms of test formats, and the application of tests to measure allergen exposure.

Oral Immunotherapy

Oral immunotherapy (OIT) is an alternative treatment of IgE-mediated food allergy that has been shown to increase tolerance threshold to many of the top food allergens, although this effect may be dependent on age, dose, frequency, and duration. OIT has been shown to be effective and safe in infants, and early initiation can improve rates of desensitization even for those foods whose natural history favors loss of allergy. Studies looking at protocol modification to improve OIT success are ongoing as is the evaluation of clinical tools to help monitor OIT effects.

Oral Immunotherapy in Food Allergy: A Critical Pediatric Perspective

There is evidence that in children with persistent IgE-mediated food allergy (FA) to cow's milk, hen's egg, and peanut, oral allergen-specific immunotherapy (OIT) may increase the reaction threshold to the culprit food allergen(s). OIT may protect patients from the occurrence of severe reactions in case of accidental ingestion of the culprit food during treatment. Notwithstanding, many gaps are still unsolved, including safety issues, identification of predictive biomarkers, and post-desensitization efficacy. In this perspective, the use of omalizumab (Anti-IgE monoclonal antibody) has been proposed as an adjunctive treatment to OIT in order to reduce the risk of allergic reactions related to OIT. This review aims to summarize the current evidence and unmet needs on OIT in children with FA to enhance the development of longitudinal, prospective, and well-designed studies able to fill the current gaps soon.

The Basophil Activation Test for Clinical Management of Food Allergies: Recent Advances and Future Directions

The basophil activation test (BAT) is an ex vivo functional assay that measures by flow cytometry the degree of basophil degranulation after stimulation with an allergen. In recent years, there has been an increased interest in the diagnostic value of the BAT as it has the potential to mimic the clinical phenotype of sIgE sensitized patients, in contrast to allergen-specific IgE levels. This diagnostic potential would be of particular interest for food allergies present early in life such as peanut, cow’s milk and eggs, which require an expensive, time-consuming and patient unfriendly oral food challenge (OFC) for diagnosis. However, routine applications of the BAT for clinical use are not yet feasible due to the lack of standardized protocols and large clinical validation studies. This review will summarize the current data regarding the application of the BAT in food allergy (FA) for cow’s milk, egg and peanut, being the most common causes of FA in children. Additionally, it will discuss the hurdles for widespread clinical use of the BAT and possible future directions for this diagnostic procedure.

Vaccines as therapies for food allergies

Food allergy is a growing public health epidemic with few available treatments beyond allergen avoidance and rescue medications for accidental exposures. A major focus of therapeutic development for food allergies is allergen-specific immunotherapy (AIT) in which patients are exposed to increasing amounts of allergen in controlled dosing to induce desensitization or tolerance. The work of the past few decades has culminated in the recent FDA approval of a peanut product for oral AIT for peanut allergies. Despite these advances, current AIT protocols are cumbersome, take a long time to reach clinical benefit and often have significant side effects. Therefore, there is a great need to develop new therapeutics for food allergy. One area of research aims to improve AIT through the use of adjuvants which are substances traditionally added to vaccines to stimulate or direct a specific immune response. Adjuvants that induce Th1-polarized and regulatory immune responses while suppressing Th2 immunity have shown the most promise in animal models. The addition of adjuvants to AIT may reduce the amount and frequency of allergen required to achieve clinical benefit and may induce more long-lasting immune responses. In this chapter, we highlight examples of adjuvanted AIT and vaccines in development to treat food allergies.

A Randomized, Open-Label Trial of Hen's Egg Oral Immunotherapy: Efficacy and Humoral Immune Responses in 50 Children

BACKGROUND

Egg allergy is the second most common food allergy in children. Persistent food allergy increases the risk of anaphylaxis and reduces the quality of life.

OBJECTIVE

To determine the efficacy of oral immunotherapy (OIT) with raw egg white powder and study its effects on humoral responses in children with persistent egg allergy.

METHODS

Fifty children aged 6 to 17 years with egg allergy, diagnosed by double-blind, placebo-controlled food challenge, were randomized 3:2 to 8 months of OIT with a maintenance dose of 1 g of egg white protein or 6 months of avoidance after which the avoidance group crossed over to OIT. We examined changes in IgE, IgG₄, and IgA concentrations to Gal d 1-4 during OIT compared with avoidance and assessed clinical reactivity at 8 and 18 months.

RESULTS

After 8 months, 22 of 50 children (44%) on OIT and 1 of 21 (4.8%) on egg avoidance were desensitized to the target dose, 23 of 50 (46%) were partially desensitized (dose <1 g), and 5 of 50 (10%) discontinued. IgG₄ concentrations to Gal d 1-4 and IgA to Gal d 1-2 increased significantly, whereas IgE to Gal d 2 decreased. A heatmap analysis of the IgE patterns revealed 3 distinct clusters linked with the clinical outcome. High baseline egg white-specific IgE and polysensitization to Gal d 1-4 related with failure to achieve the maintenance dose at 8 months. After 18 months of treatment, 36 of 50 patients (72%) were desensitized and 8 of 50 (16%) partially desensitized.

CONCLUSIONS

OIT with raw egg enables liberation of egg products into the daily diet in most patients. Subjects with high egg white-specific IgE concentrations and sensitization to multiple egg allergen components at baseline benefit from prolonged treatment.

A novel approach to ameliorate experimental milk allergy based on the oral administration of a short soy cross-reactive peptide

Food allergy is on the rise, and preventive/therapeutic procedures are needed. We explored a preventive protocol for milk allergy with the oral administration of a Gly-m-Bd-30K soy-derived peptide that contains cross-reactive epitopes with bovine caseins. B/T-cross-reactive epitopes were mapped using milk-specific human sera and monoclonal antibodies on overlapping and recombinant peptides of Gly-m-Bd-30K by SPOT and cell proliferation assays. Bioinformatics tools were used to characterize epitopes on the 3D-modelled molecule, and to predict the binding to HLA alleles. The peptide was orally administrated to mice that were then IgE-sensitized to milk proteins. Immunodominant B-epitopes were mainly located on the surface of the Nt-fragment. The use of a soy-peptide-containing an immunodominant cross-reactive T-epitope, along with a single B epitope, prevents IgE-mediated milk sensitization through the induction of Th1-mediated immunity and induction of blocking IgG. The use of a safe soy-peptide may represent a promising alternative for preventing milk allergy.

Immunological Outcomes of Allergen-Specific Immunotherapy in Food Allergy

IgE-mediated food allergies are caused by adverse immunologic responses to food proteins. Allergic reactions may present locally in different tissues such as skin, gastrointestinal and respiratory tract and may result is systemic life-threatening reactions. During the last decades, the prevalence of food allergies has significantly increased throughout the world, and considerable efforts have been made to develop curative therapies. Food allergen immunotherapy is a promising therapeutic approach for food allergies that is based on the administration of increasing doses of culprit food extracts, or purified, and sometime modified food allergens. Different routes of administration for food allergen immunotherapy including oral, sublingual, epicutaneous and subcutaneous regimens are being evaluated. Although a wealth of data from clinical food allergen immunotherapy trials has been obtained, a lack of consistency in assessed clinical and immunological outcome measures presents a major hurdle for evaluating these new treatments. Coordinated efforts are needed to establish standardized outcome measures to be applied in food allergy immunotherapy studies, allowing for better harmonization of data and setting the standards for the future research. Several immunological parameters have been measured in food allergen immunotherapy, including allergen-specific immunoglobulin levels, basophil activation, cytokines, and other soluble biomarkers, T cell and B cell responses and skin prick tests. In this review we discuss different immunological parameters and assess their applicability as potential outcome measures for food allergen immunotherapy that may be included in such a standardized set of outcome measures.

Safety of Food Oral Immunotherapy: What We Know, and What We Need to Learn

Oral immunotherapy (OIT) for food allergy entails a risk of adverse reactions, including anaphylaxis. This safety concern is the major barrier for OIT to become a therapeutic option in clinical practice. The high heterogeneity in safety reporting of OIT studies prevents setting the safety profile accurately. An international consensus is needed to facilitate the analysis of large pooled clinical data with homogeneous safety reporting, that together with integrated omics, and patients/families' opinions, may help stratify the patients' risk and needs, and help developing safe(r) individualized care pathways. This will give OIT the right place in the food allergy therapy.

Oral Immunotherapy (OIT): A Personalized Medicine

Oral Immunotherapy (OIT), a promising allergen-specific approach in the management of Food Allergies (FA), is based on the administration of increasing doses of the culprit food until reaching a maintenance dose. Each step should be adapted to the patient, and OIT should be considered an individualized treatment. Recent studies focused on the standardization and identification of novel biomarkers in order to correlate endotypes with phenotypes in the field of FA.

Allergen immunotherapy for IgE-mediated food allergy: There is a measure in everything to a proper proportion of therapy

IgE-mediated food allergy (FA) is a potentially life-threatening condition with a negative impact on quality of life and an increasing prevalence in westernized countries in the recent two decades. A strict avoidance of the triggering food(s) represents the current standard approach. However, an elimination diet may be difficult and frustrating, in particular for common foods, (eg, milk, egg, and peanut). Food allergy immunotherapy (FA-AIT) may provide an active treatment that enables to increase the amount of food that the patient can intake without reaction during treatment (ie, desensitization), and reduces the risk of potential life-threatening allergic reaction in the event of accidental ingestion. However, several gaps need still to be filled. A memorable Latin orator stated: "Est modus in rebus" (Horace, Sermones I, 1, 106-07). This sentence remembers that there is a measure in everything to a proper proportion of therapy. The common sense of measure should find application in each stage of treatment. A personalized approaching should consider the specific willing and features of each patient. Efforts are devoted to improve the efficacy, the safety but also the quality of life of patients suffering from FA. In the near future, it will be important to clarify immunologic pathways of FA-AIT, and to identify reliable biomarkers in order to recognize the most suitable candidates to FA-AIT and algorithms for treatments tailored on well-characterized subpopulations of patients.

Hypoallergenic Proteins for the Treatment of Food Allergy

PURPOSE OF REVIEW

Food allergy is a growing health problem worldwide that impacts millions of individuals. Current treatment options are limited and strict dietary avoidance remains the standard of care. Immunotherapy using whole, native allergens is under active clinical investigation but harbors the risk of severe side effects including anaphylaxis. Newer food-specific therapies with hypoallergenic proteins may potentially offer safer treatment alternatives, and this review seeks to investigate the evidence supporting the use of these modalities.

RECENT FINDINGS

The utilization of different methods to alter allergen structure and IgE binding leads to reduced allergenicity and decreases the risk for systemic reactions, making the use of potential therapies including extensively heated egg/milk, peptide immunotherapy, recombinant allergen immunotherapy, and DNA vaccines safe and possibly efficacious forms of treatment in food allergy. However, for the majority of these treatment modalities, limited data currently exists looking at the safety and efficacy in human subjects with food allergy. This review provides a comprehensive overview of the current evidence examining the safety and efficacy of hypoallergenic proteins in the treatment of food allergies.

The Impact of Baked Egg and Baked Milk Diets on IgE- and Non-IgE-Mediated Allergy

Baked milk (BM) and baked egg (BE) diets are increasingly used in the management of milk and egg allergy, rather than avoidance. Children with tolerance versus reactivity to BM and BE may have smaller skin prick test and lower specific IgE, and BM-tolerant children have less basophil reactivity and more peripheral T regulatory cells. However, most milk- and egg-allergic children tolerate BM and BE and an individual's reactivity is unpredictable. Non-reactivity is due to conformational changes in the allergens. Significant differences in the published advice about methods of introduction exist from graded introduction at home to a medically supervised full dose. These approaches carry different risks and may have different immunological effects. Reactivity to BM is a predictor of a severe milk allergy. Therefore, medical supervision for BM and BE introduction is prudent. The baked diet allows dietary liberation. Most, but not all, BM- and BE-tolerant children continue eating the baked foods. The prognosis of children who can eat BM and BE is favorable with likely resolution of their allergy over the next few years. Murine models of BE diets demonstrate that heated egg can impart clinical protection against anaphylaxis and cause immune changes. Most observational human studies of BM and BE diets demonstrate clinical resolution of allergy and favorable immune changes versus regular care controls. However, the one randomized controlled trial for the BE diet in BE-tolerant children did not support an immune-modifying effect of the BE diet. Another study of BE immunotherapy is expected to be completed in 2018. There is currently no evidence for prevention of allergy with the baked diets. There may be a future role for BM and BE in liberating the diets of individuals with non-IgE-mediated allergy given recent studies that a subset of these patients can consume BM without a clinical reaction.

Debates in Allergy Medicine: Oral immunotherapy shortens the duration of milk and egg allergy - the con argument

Oral immunotherapy (OIT) has been shown to be effective for inducing desensitization in children with cow’s milk and egg allergy. In contrast, there is limited evidence that OIT can induce tolerance or sustained unresponsiveness in food allergic patients. Sustained unresponsiveness, determined by a food challenge following a period of secondary avoidance, has been suggested to reflect a more enduring state of tolerance and is pertinent when considering the ability of OIT to shorten the duration of food allergy. While it has been shown that children who tolerate baked forms of egg and milk are more likely to develop tolerance compared to those who are allergic to baked forms of these foods, there is no convincing evidence that OIT using modified allergen in baked foods can hasten resolution of cow’s milk and egg allergy. Instead, it is likely that baked milk and baked egg tolerant children represent a sub-phenotype of milk and egg allergy that is more likely to resolve spontaneously over time.

Update on oral immunotherapy for egg allergy

Oral immunotherapy (OIT) is an emerging treatment of IgE-mediated egg allergy. In the past decade, a multitude of studies have assessed the potential for egg OIT to induce clinical desensitization. The following review will evaluate the efficacy and safety of this therapy as determined by randomized controlled, non-randomized controlled and uncontrolled trials. Recent studies using reduced allergenic egg products and anti-IgE assisted therapy to improve egg OIT safety will also be discussed. Recent advances in the mechanisms underlying food OIT suggest that certain immune parameters may be helpful in monitoring response to therapy, including egg OIT. Although, egg OIT is consistently shown to be effective with regards to clinical desensitization, fewer studies have looked at persistent tolerance or sustained unresponsiveness. Limited results of long-term follow-up trials suggest that this therapy may have disease-modifying effects. In general, the comparison of studies is complicated by major differences in study designs, OIT protocols and endpoints.

Oral and sublingual immunotherapy for egg allergy

BACKGROUND

Clinical egg allergy is a common food allergy. Current management relies upon strict allergen avoidance. Oral immunotherapy might be an optional treatment, through desensitization to egg allergen.

OBJECTIVES

To determine the efficacy and safety of oral and sublingual immunotherapy in children and adults with immunoglobulin E (IgE)-mediated egg allergy as compared to a placebo treatment or an avoidance strategy.

SEARCH METHODS

We searched 13 databases for journal articles, conference proceedings, theses and trials registers using a combination of subject headings and text words (last search 31 March 2017).

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing oral immunotherapy or sublingual immunotherapy administered by any protocol with placebo or an elimination diet. Participants were children or adults with clinical egg allergy.

DATA COLLECTION AND ANALYSIS

We retrieved 97 studies from the electronic searches. We selected studies, extracted data and assessed the methodological quality. We attempted to contact the study investigators to obtain the unpublished data, wherever possible. We used the I² statistic to assess statistical heterogeneity. We estimated a pooled risk ratio (RR) with 95% confidence interval (CI) for each outcome using a Mantel-Haenzel fixed-effect model if statistical heterogeneity was low (I² value less than 50%). We rated the quality of evidence for all outcomes using GRADE.

MAIN RESULTS

We included 10 RCTs that met our inclusion criteria, that involved a total of 439 children (oral immunotherapy 249; control intervention 190), aged 1 year to 18 years. Each study used a different oral immunotherapy protocol; none used sublingual immunotherapy. Three studies used placebo and seven used an egg avoidance diet as the control. Primary outcomes were: an increased amount of egg that can be ingested and tolerated without adverse events while receiving allergen-specific oral immunotherapy or sublingual immunotherapy, compared to control; and a complete recovery from egg allergy after completion of oral immunotherapy or sublingual immunotherapy, compared to control. Most children (82%) in the oral immunotherapy group could ingest a partial serving of egg (1 g to 7.5 g) compared to 10% of control group children (RR 7.48, 95% CI 4.91 to 11.38; RD 0.73, 95% CI 0.67 to 0.80). Fewer than half (45%) of children receiving oral immunotherapy were able to tolerate a full serving of egg compared to 10% of the control group (RR 4.25, 95% CI 2.77 to 6.53; RD 0.35, 95% CI 0.28 to 0.43). All 10 trials reported numbers of children with serious adverse events (SAEs) and numbers of children with mild-to-severe adverse events. SAEs requiring epinephrine/adrenaline presented in 21/249 (8.4%) of children in the oral immunotherapy group, and none in the control group. Mild-to-severe adverse events were frequent; 75% of children presented mild-to-severe adverse events during oral immunotherapy treatment versus 6.8% of the control group (RR 8.35, 95% CI 5.31 to 13.12). Of note, seven studies used an egg avoidance diet as the control. Adverse events occurred in 4.2% of children, which may relate to accidental ingestion of egg-containing food. Three studies used a placebo control with adverse events present in 2.6% of children. Overall, there was inconsistent methodological rigour in the trials. All studies enrolled small numbers of children and used different methods to provide oral immunotherapy. Eight included studies were judged to be at high risk of bias in at least one domain. Furthermore, the quality of evidence was judged to be low due to small numbers of participants and events, and possible biases.

AUTHORS' CONCLUSIONS

Frequent and increasing exposure to egg over one to two years in people who are allergic to egg builds tolerance, with almost everyone becoming more tolerant compared with a minority in the control group and almost half of people being totally tolerant of egg by the end of treatment compared with 1 in 10 people who avoid egg. However, nearly all who received treatment experienced adverse events, mainly allergy-related. We found that 1 in 12 children had serious allergic reactions requiring adrenaline, and some people gave up oral immunotherapy. It appears that oral immunotherapy for egg allergy is effective, but confidence in the trade-off between benefits and harms is low; because there was a small number of trials with few participants, and methodological problems with some trials.

Current Status of Potential Therapies for IgE-Mediated Food Allergy

PURPOSE OF REVIEW

The goal of this review is to provide the reader with an updated summary of published trial data regarding the use of oral immunotherapy (OIT), sublingual immunotherapy (SLIT), and epicutaneous immunotherapy (EPIT) for treatment of IgE-mediated food allergies.

RECENT FINDINGS

Data from phase 2 trials for treatment of peanut allergy with OIT and EPIT reveal an increase in the threshold of reactivity for peanut-allergic children. Compared to EPIT, OIT promotes a greater increase in the threshold of reactivity; however, adverse events are more common with OIT. OIT, EPIT, and SLIT appear to modulate the immune response for some food-allergic individuals. Data regarding utility for treatment of food allergies regardless of modality is limited to few foods, as is investigation into treatment of food-allergic infants, young children, and adults. Future trials are likely to focus on young children, food allergies other than peanut, and treatment of multifood-allergic individuals.

Food allergy in EAACI journals (2016)

Over the last years we have observed considerable progress in the area of food allergy, particularly in children. This review article focusses on important contributions which have lately been published in the three journals of the European Academy of Allergy and Clinical Immunology. A better understanding of allergens as well as the mechanisms of sensitization and tolerance induction may hopefully lead to a more targeted management of food allergy in the near future.

Immunomodulating peptides for food allergy prevention and treatment

Among the most promising strategies currently assayed against IgE-mediated allergic diseases stands the possibility of using immunomodulating peptides to induce oral tolerance toward offending food allergens or even to prevent allergic sensitization. This review focuses on the beneficial effects of food derived immunomodulating peptides on food allergy, which can be directly exerted in the intestinal tract or once being absorbed through the intestinal epithelial barrier to interact with immune cells. Food peptides influence intestinal homeostasis by maintaining and reinforcing barrier function or affecting intestinal cell-signalling to nearby immune cells and mucus secretion. In addition, they can stimulate cells of the innate and adaptive immune system while supressing inflammatory responses. Peptides represent an attractive alternative to whole allergens to enhance the safety and efficacy of immunotherapy treatments. The conclusions drawn from curative and preventive experiments in murine models are promising, although there is a need for more pre-clinical studies to further explore the immunomodulating strategy and its mechanisms and for a deeper knowledge of the peptide sequence and structural requirements that determine the immunoregulatory function.

The current state of food allergy therapeutics

The prevalence of IgE mediated food allergy is an increasing public health concern. The current standard of treatment is strict avoidance of the offending food(s). There are no FDA approved treatments for food allergy. This review will provide an overview of strategies currently under investigation for the treatment of food allergy. The main focus of research has been directed at various forms of immunotherapy, including oral, sublingual and epicutaneous delivery routes. While oral immunotherapy (OIT) has shown the greatest promise for efficacy in terms of amount of protein that can be ingested, it has also demonstrated less tolerability and a less favorable safety profile as compared to sublingual immunotherapy (SLIT) and epicutaneous immunotherapy (EPIT), which offers the least protection but has the best safety and tolerability profile. Investigation is also underway for modified antigens that may be used for immunotherapy and for adjuncts that may help facilitate immunotherapy, including biologics such as anti-IgE therapy, and also probiotics. There are also a number of preclinical concepts that are being evaluated to manipulate the antigens and/or the immune system that may one day be translatable to patients.

Advances and highlights in allergen immunotherapy: On the way to sustained clinical and immunologic tolerance

Allergen immunotherapy (AIT) is an effective treatment strategy for allergic diseases and has been used for more than 100 years. In recent years, however, the expectations on concepts, conduct, statistical evaluation, and reporting have developed significantly. Products have undergone dose-response and confirmative studies in adults and children to provide evidence for the optimal dosage, safety, and efficacy of AIT vaccines using subcutaneous and sublingual delivery pathways in large patient cohorts, ensuring solid conclusions to be drawn from them for the advantage of patients and societies alike. Those standards should be followed today, and products answering to them should be preferred over others lacking optimization and proof of efficacy and safety. Molecular and cellular mechanisms of AIT include early mast cell and basophil desensitization effects, regulation of T- and B-cell responses, regulation of IgE and IgG₄ production, and inhibition of responses from eosinophils, mast cells, and basophils in the affected tissues. There were many developments to improve vaccination strategies, demonstration of new molecules involved in molecular mechanisms, and demonstration of new biomarkers for AIT during the last few years. The combination of probiotics, vitamins, and biological agents with AIT is highlighting current advances. Development of allergoids and recombinant and hypoallergenic vaccines to skew the immune response from IgE to IgG₄ and regulation of dendritic cell, mast cell, basophil, innate lymphoid cell, T-cell, and B-cell responses to allergens are also discussed in detail.

Clinical aspects of oral immunotherapy for the treatment of allergies

Studies on oral immunotherapy (OIT) have been increasing worldwide. Nevertheless, some concerns exist with this treatment. The rate of long-term sustained unresponsiveness is quite low; moreover, the desensitization or sustained unresponsiveness does not equate to tolerance. Furthermore, adverse reactions are frequent. Therefore, safe and feasible methods for long-term therapies are needed. Novel therapies such as low-dose OIT, hypoallergenic products, and OIT in combination with omalizumab are reported as effective for inducing sustained unresponsiveness and may lead to fewer adverse reactions than standard OIT. Increased safety will contribute to feasibility of OIT. Currently, oral food challenge (OFC) with the low target dose has been reported. We may reduce the need for OIT by implementing low-dose OFC. More effective, safe, and feasible OIT strategies are needed.

Oral immunotherapy for food allergy: A Spanish guideline. Immunotherapy egg and milk Spanish guide (items guide). Part I: Cow milk and egg oral immunotherapy: Introduction, methodology, rationale, current state, indications contraindications and oral immunotherapy build-up phase

INTRODUCTION

Cow's milk and egg are the most frequent causes of food allergy in the first years of life. Treatments such as oral immunotherapy (OIT) have been investigated as an alternative to avoidance diets. No clinical practice guides on the management of OIT with milk and egg are currently available.

OBJECTIVES

To develop a clinical guide on OIT based on the available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published in the period between 1984 and June 2016, Doctoral Theses published in Spain, and summaries of communications at congresses (SEAIC, SEICAP, EAACI, AAAAI), with evaluation of the opinion consensus established by a group of experts pertaining to the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations have been established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of suffering adverse reactions.

CONCLUSIONS

A clinical practice guide is presented for the management of OIT with milk and egg, based on the opinion consensus of Spanish experts.

Treatment of allergic children - Where is the progress (for the practicing allergist)?

For any kind of therapeutic intervention in allergic diseases such as environmental control, pharmacological, or immunomodulating treatment including educational programs, children are addressed separately from adults. Health authorities like the Food and Drug Administration in the United States of America or the European Medicine Agency in Europe request a specific 'Pediatric investigational plan' with studies addressing dose-response relationship, safety, and efficacy for infants, children, and adolescents. During the last 2 years, promising advances have been reported for the treatment of a variety of allergic and immunologic disorders. This review summarizes the progress in the treatment of pediatric asthma and allergic diseases, based on publications of approximately the last 2.5 years (end of 2013 until May 2016) in and beyond this journal. Meanwhile, it highlights areas with promising novel therapeutic approaches, which are likely to change treatment for allergic children in the near future.