Induction of sustained unresponsiveness after egg oral immunotherapy compared to baked egg therapy in children with egg allergy

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.

ADP101 multifood oral immunotherapy for food-allergic patients: Harmony phase 1/2 randomized clinical trial

Background

Oral immunotherapy is an established approach to desensitize the immune system in the context of allergic disease; however, the only currently approved product is for peanut allergy. ADP101 is a novel, pharmaceutical-grade, multifood oral immunotherapy in development to simultaneously treat single or multiple food allergies, containing allergenic proteins from 15 foods in equal parts by protein weight.

Objective

The phase 1/2 Harmony trial (NCT04856865) evaluated efficacy and safety of ADP101 in participants with qualifying allergy to 1 to 5 foods in ADP101, defined as dose-limiting symptoms with a ≤100 mg challenge dose during double-blind, placebo-controlled food challenge (DBPCFC).

Methods

Participants were randomized to low-dose (1500 mg/d; 100 mg protein per food) or high-dose (4500 mg/d; 300 mg protein per food) ADP101, or matched placebo, with dose escalation followed by daily maintenance dosing over 40 weeks. The primary endpoint was the proportion of participants tolerating a ≥600 mg challenge dose of a single qualifying food without dose-limiting symptoms at the Week 40 Exit DBPCFC (ie, responders).

Results

In the primary analysis population (61 pediatric participants aged 4-17 years), a greater response rate was observed in both the high-dose ADP101 (55.0%) and low-dose ADP101 (38.1%) groups compared with pooled placebo (20.0%) (nominal P = .048, P = .306, respectively; adjusted for multiple comparisons, P = .097, P = .306, respectively). Desensitization to ≥2 foods was observed in individuals with multiple food allergies, as was desensitization at levels over 600 mg. ADP101-treated participants showed an overall reduction in skin-prick test reactivity, with an increase in maximum tolerated dose across the majority of foods tested. Adverse events were mostly mild or moderate, with no life-threatening events or deaths.

Conclusions

The study did not meet its primary endpoint, but ADP101 demonstrated a favorable safety profile and increased the reactive threshold in DBPCFC in pediatric participants with single or multiple food allergies across multiple endpoints, warranting further clinical investigation.

Detection of egg white allergy in children by specific IgE microarray chemiluminescence immunoassay

BACKGROUND

Allergen testing has emerged as a pivotal component in prevention and treatment strategies for allergic diseases among children and the utilization of specific IgE (sIgE) through a fully automated chemiluminescent microarray immunoassay (CLMIA) has emerged as a promising trend in the simultaneous detection of multiple allergenic components of children.

METHODS

The accuracy and reliability of CLMIA were verified using children's serum samples that concentrated on allergens. the allergens. The clinical diagnostic practicability of CLMIA was assessed through comprehensive evaluations including measurements of the limit of detection (LOD), intra-batch, and inter-batch precision, linearity analysis, the cross-contamination rate, and the concordance rate with the Phadia system.

RESULTS

After the optimization process of CLMIA, the LODs for allergens were calculated to be below 0.01 kU/L, demonstrating the high sensitivity of CLMIA. All components exhibited good linearity within the range of 0.1-100.0 kU/L and the coefficient of determinations (R2 > 0.99). The data of intra-batch precision (<10 %) and inter-batch data (<15 %) illustrated the high reproducibility of CLMIA. The cross-contamination rates for allergens (<0.5 %) showed the high accuracy of CLMIA without interfering. The positive concordance rate between CLMIA and the Phadia system exceeds 90 % with a good negative concordance rate (>85 %) and the Kappa coefficients (>0.8), suggesting the close alignment of CLMIA and the Phadia system and showing the satisfactory clinical potential of CLMIA in children's allergy disease.

CONCLUSIONS

The application of CLMIA has been promising in allergen testing, especially for detecting multiple allergenic components in children.

Evolving Food Allergy Clinical Trials to Become More Patient-Centered

The current US Food and Drug Administration (FDA) paradigm may not fully capture important patient-centered outcomes or measure a primary outcome that is truly meaningful to patients. Patient-reported outcome measures (PROMs) are standardized tools measuring the patient's experience in food allergy clinical trials, which can help support shared decision-making (SDM) and further our understanding of treatment impact. Food allergy PROMs include quality of life (QoL), health state utility (HSU), severity, and self-efficacy measures. Currently, FDA registration trials for product approval only consider a fixed increase in allergen threshold from pre-to-post intervention as a primary outcome (vs a more flexible "X-fold" increase not accounting for an upper and lower specific threshold), though many use QoL as a secondary outcome for patient-centered assessment of treatment impact. Currently used QoL PROMs were not designed to measure change on therapy nor measure HSU (eg, quantitative risk a patient may be willing to take to improve their current health), which can be used to determine therapy value. Although the current paradigm for primary and secondary outcomes in food allergy clinical trials was appropriate at the early stages of food allergy therapy development when conceived in the late 2000s and early 2010s, in the 2020s, these outcome choices risk being stagnant and outdated. As such, the current paradigm for food allergy outcomes should evolve to incorporate more patient-centered primary outcome measures that patient data indicate are meaningful, so outcomes more realistically reflect a therapy's impact. This evolution will better support SDM discussions as patients consider their therapy options and can inform new product development.

Arabinogalactans-rich microwave-assisted nanomucilage originated from garden cress seeds as an egg replacement in the production of cupcakes: Market orientation and in vitro digestibility

The increasing demand for functional foods arises from concerns regarding food allergies, dietary restrictions, and ethical considerations related to egg consumption. Consequently, this study investigates the feasibility of using arabinogalactan-rich nanomucilage derived from garden cress seeds as an egg replacement in cupcake production. The microwave-assisted process resulted in 23.28 ± 0.34 % yield and it demonstrated a nanoscale particle size of 146.3 ± 2.67 nm. Smooth surfaces with spherical concavities-shaped particles were observed containing carbohydrate and protein-based functional groups. A market survey involving 250 participants indicated a notable interest in egg-free cupcakes, with 75% of respondents determining a willingness to sample them. Cupcakes containing 15% nanomucilage (C3) exhibited comparable sensory acceptability and similar physicochemical properties, along with significantly improved hardness (751.03 ± 1.24 g), resilience (23.98 ± 0.56), and chewiness (513.75 ± 1.37 g) when compared to egg-based cupcakes. In vitro digestibility exhibited a significant reduction in the area under the curve for reducing sugars in C3 (155.68 mg g-1) relative to the control (238.83 mg g-1), suggesting a lower glycemic index. Hence, this study reveals that garden cress seed mucilage could be an effective egg substitute in cupcakes, offering comparable sensory and textural attributes with potentially lower glycemic index.

The Safety and Efficacy of Baked Egg and Milk Dietary Advancement Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

Cow's milk and egg allergy affect approximately 1.9% and 0.9% of children, respectively. Dietary advancement therapies (DATs), including milk (ML) and egg (EL) ladders, and baked milk (BM-OIT) and baked egg (BE-OIT) oral immunotherapy, are potential therapeutic options for these patients.

OBJECTIVE

To perform systematic review and meta-analysis of the safety and efficacy of DATs in children with IgE-mediated milk or egg allergy.

METHODS

A systematic literature review was conducted, exploring 22 potential outcomes, with meta-analysis performed where ≥3 studies reported data. The GRADE approach was used to determine the certainty of evidence for each outcome, and the Johanna Briggs Institute tools were used for determining risk of bias.

RESULTS

Twenty-nine studies met inclusion criteria among 9946 titles screened. Tolerance occurred in 69% of EL, 58% of ML, 49% of BE-OIT, and 29% of BM-OIT patients. All-severity allergic reactions occurred in 21% of EL, 25% of ML, 20% of BE-OIT, and 61% of BM-OIT patients, with epinephrine use in 3% of EL, 2% of ML, and 9% of BM-OIT patients. At-home reactions occurred in 19% of BE-OIT and 10% of BM-OIT patients. Discontinuation occurred in 14% of EL, 17% of ML, 17% of BE-OIT, and 20% of BM-OIT patients. The mean time to BE egg and BE-OIT tolerance was 13.25 months (4 studies) and 19.1 months (3 studies). Certainty of evidence was very low, and risk of bias high. Study heterogeneity was high, attributable to multiple factors.

CONCLUSIONS

There is very low certainty of evidence supporting DAT safety and efficacy. We cannot conclude that DAT accelerates tolerance development.

Recent advances in food allergen immunotherapy

Food allergies can pose significant risks and profoundly impact the quality of life of children and their families, making them a major public health concern. Allergen avoidance has been the traditional mainstay of treatment; however, recent research has focused on various approaches to food allergen immunotherapy. This review summarizes the recent advancements in oral, sublingual, and epicutaneous immunotherapies, highlighting their respective advantages and disadvantages. The ultimate goal of food allergen immunotherapy is to maximize efficacy while minimizing risks, leading to the exploration of strategies such as low-dose immunotherapy and the use of biologics. When selecting candidates for immunotherapy among patients with food allergies, factors such as allergen characteristics, the likelihood of natural resolution, age, symptom severity, and impact on quality of life require consideration, and an individualized approach should be adopted to determine the most suitable treatment method.

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.

Partial Egg Consumption Modifies the Diagnostic Performance of Allergy Tests to Predict Outcome of Double-Blind Placebo-Controlled Food Challenges to Egg

BACKGROUND

Many children are consuming some egg when they are diagnosed with egg allergy. We hypothesized that egg consumption could modify the diagnostic performance of allergy tests.

OBJECTIVE

To stratify diagnostic performance of tests according to egg consumption status.

METHODS

The BAT2 study (NCT03309488) participants underwent oral food challenge (OFC), food-frequency questionnaires, skin prick test (SPT), specific immunoglobulin E (sIgE) and specific immunoglobulin G4 (sIgG4) and basophil activation test (BAT).

RESULTS

At study entry, 45% of participants reported partial egg consumption ("consumers") and 55% were avoiding egg strictly ("avoiders"). Avoiders had larger SPT (P < .001), higher BAT to egg (P < .001), sIgE to egg white (EW; P = .001) and to ovalbumin (OVA; P = .001), but not to ovomucoid (P = .231). Consumers had higher levels of sIgG4 to all egg allergens (P < .001) than avoiders. In consumers, the test with the best diagnostic performance was BAT (area under the curve [AUC] = .912) followed by SPT to raw egg (AUC = 0.805), EW-sIgE (AUC = 0.738), and OVA-sIgE (AUC = 0.732). In avoiders, the best tests were BAT (AUC = 0.834) and EW-sIgE (AUC = 0.833) followed by OVA-sIgE (AUC = 0.793) and SPT to EW (AUC=0.789). Using 100% sensitivity and 100% specificity cut-offs, the proportion of patients requiring OFC were 33% for BAT, 53% for SPT to raw egg, 61% for OVA-sIgE, and 73% for EW-sIgE for consumers; and 73% for BAT, 79% for EW-sIgE, and 93% for SPT to EW for avoiders.

CONCLUSIONS

The diagnostic performance of tests is influenced by the immunomodulatory effect of egg consumption. BAT is the most reliable test and reduced the need for OFC, particularly in partial egg consumers.

Practical issues of oral immunotherapy for egg or milk allergy

Oral immunotherapy (OIT) has been recommended to reduce parental burden related to strict allergen avoidance and induce desensitization and immune tolerance for patients with long-lasting allergies to hen's eggs (HE) or cow's milk (CM). OIT should be monitored by pediatric allergists specializing in OIT and oral food challenge tests to manage allergic reactions. Although a previous history of anaphylaxis or multiple food allergies is not a contraindication to OIT, it is contraindicated if the patient has uncontrolled asthma, a malignancy, active systemic autoimmune disorders, or diseases requiring treatment with beta-blockers. A variety of OIT protocols have been de veloped to ensure better outcomes and safe up-dosing, including adjunctive therapies with biologics. This review provides insight into the practical issues of various immunotherapy options for children with HE or CM allergies.

Baked milk and egg diets revisited

Most children with milk and egg allergy are nonreactive to modified forms of milk and egg in bakery products such as muffins because of conformational changes in proteins. These baked milk (BM) and baked egg (BE) diets have become commonplace in the management of milk and egg allergy, respectively. Current laboratory- and skin test-based diagnostic approaches remain limited in their ability to predict BM/BE tolerance, resulting in various approaches to introduce these foods. One approach to introduce BM/BE is to offer a medically supervised oral food challenge and then advise dietary introduction of baked products for children who have tolerance. Another approach is adapted from a home-based protocol of graded ingestion of BM or BE originally intended for non-IgE mediated allergy, often referred to as a "ladder." The ladder advises home ingestion of increasing amounts of BM or BE. For children who have allergy to BM or BE, the ladder is essentially oral immunotherapy, although not always labeled or recognized as such. Risk assessment and education of patients suitable for home introduction are essential. A home approach that may be called a ladder can also be used to escalate diets after demonstrated tolerance of baked forms by introducing lesser cooked forms of milk or egg after tolerating BM or BE. A randomized controlled trial provided clear evidence that baked diets can hasten the resolution of IgE-mediated milk allergy. Moreover, BM/BE foods have an emerging role in the treatment of non-IgE-mediated allergy. There is tangential evidence for BM and BE diets in the prevention of IgE-mediated allergy.

Intervention Efficacy of Slightly Processed Allergen/Meat in Oral Immunotherapy for Seafood Allergy: A Systematic Review, Meta-Analysis, and Meta-Regression Analysis in Mouse Models and Clinical Patients

Background: Seafood allergy is a significant global health concern that greatly impacts a patient's quality of life. The intervention efficacy of oral immunotherapy (OIT), an emerging intervention strategy, for seafood allergy remains controversial. This study aimed to perform a systematic review and meta-analysis to evaluate the efficacy of slightly processed allergen/meat from fish and crustacea in OIT, both in mouse models and clinical patients. Methods: A comprehensive literature search was performed in four mainstream databases and the EBSCOhost database to identify all relevant case-control and cohort studies. The aim was to elucidate the intervention efficacy, encompassing various processing methods and assessing the efficacy of multiple major allergens in OIT. Results: The meta-analysis included five case-control studies on crustacean allergens in mouse models and 11 cohort studies on meat from fish and crustacea in clinical patients for final quantitative assessments. In mouse models, crustacean allergen substantially decreased the anaphylactic score after OIT treatment (mean difference (MD) = -1.30, p < 0.01). Subgroup analyses with low-level heterogeneities provided more reliable results for crab species (MD = -0.63, p < 0.01, I2 = 0), arginine kinase allergen (MD = -0.83, p < 0.01, I2 = 0), and Maillard reaction processing method (MD = -0.65, p < 0.01, I2 = 29%), respectively. In clinical patients, the main meta-analysis showed that the slightly processed meat significantly increased the incidence rate of oral tolerance (OT, incidence rate ratio (IRR) = 2.90, p < 0.01). Subgroup analyses for fish meat (IRR = 2.79, p < 0.01) and a simple cooking treatment (IRR = 2.36, p = 0.01) also demonstrated a substantial increase in the incidence rate of OT. Sensitivity and meta-regression analyses successfully identified specific studies contributing to heterogeneity in mouse models and clinical patients, although these studies did not impact the overall significant pooled effects. Conclusions: This meta-analysis provides preliminary evidence for the high intervention efficacy of slightly processed allergen/meat from fish and crustacea in OIT, both in mouse models and clinical patients. The Maillard reaction and cooking processing methods may emerge as potentially effective approaches to treating allergen/meat in OIT for clinical patients, offering a promising and specific treatment strategy for seafood allergy. However, these findings should be interpreted cautiously, and further supporting evidence is necessary.

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.

Basophil activation test as predictor of severity and threshold of allergic reactions to egg

BACKGROUND

Identifying patients at risk of severe allergic reactions and/or low threshold of reactivity is very important, particularly for staple foods like egg.

METHODS

One hundred and fifty children underwent double-blind placebo-controlled food challenge (DBPCFC) to baked egg (BE), skin prick testing and blood collection for serology and basophil activation test (BAT). Patients who passed BE DBPCFC underwent loosely cooked egg (LCE) DBPCFC. Severity of allergic reactions was classified following Practall guidelines and threshold dose was determined during DBPCFC.

RESULTS

Sixty out of 150 (40%) children reacted to BE and 16 out of 77 (21%) to LCE on DBPCFC. Considering DBPCFC to BE, 23 children (38%) had severe reactions and 33 (55%) reacted to 0.13 g or less of egg protein (low threshold group). Two children (2 out of 16 = 12%) had severe reactions to LCE. Demographic, clinical and most immunological features were not significantly different between severe/non-severe BE reactors or low/high threshold groups. Severe BE reactors had higher ovomucoid-sIgE (p = .009) and higher BAT to BE (p = .001). Patients with lower threshold to BE had higher IgE-specific activity (p = .027) and BAT to egg (p = .007) but lower severity score (p = .008). Optimal cut-offs for ovomucoid-sIgE had 100% sensitivity, 35% specificity and 60% accuracy and for BAT 76% sensitivity, 74% specificity and 75% accuracy to identify BE severe reactors. Optimal cut-offs for specific activity had 70% sensitivity, 68% specificity and 69% accuracy and for BAT 70% sensitivity, 72% specificity and 71% accuracy to identify low threshold patients.

CONCLUSIONS

BAT was the best biomarker to predict severity and threshold of allergic reactions to BE and can be useful when making decisions about management of egg allergy.

Food Allergen Immunotherapy in the Treatment of Patients with IgE-Mediated Food Allergy

The prevalence of allergic diseases, including food allergy, is increasing, especially in developed countries. Implementation of an elimination diet is not a sufficient therapeutic strategy in patients with food allergy, whose quality of life is significantly impaired. In recent years, new effective therapeutic strategies have been developed, such as the application of oral, sublingual, and epicutaneous immunotherapy. Oral immunotherapy is the most often applied strategy because of its effectiveness and ease of application, with an acceptable safety profile. The effectiveness of oral immunotherapy in patients with egg, cow's milk, and peanut allergy has been proven both in terms of raising of the threshold and the development of tolerance, and in some patients, the development of sustainable unresponsiveness. Although oral immunotherapy is an effective treatment for food allergy, several limitations, including a long duration and a significant rate of reported adverse events, reduces its success. Therefore, new therapeutic options, such as treatment with biologicals, either as combinations with food allergen immunotherapy or as monotherapy with the aim of improving the efficacy and safety of treatment, are being investigated.

[Treatment for living with food allergy]

The treatment of food allergy involves completely removing the allergenic food from the diet, careful label reading, and ingredient awareness. Family education is crucial, understanding alternative names for the allergen. An emergency action plan provided by the doctor, with clear instructions for epinephrine application and when to seek medical attention, is essential. For mild to moderate symptoms, oral antihistamines may be prescribed. Psychological support is necessary due to emotional repercussions. Collaboration with an allergy specialist is crucial for personalized treatment. Natural tolerance to the food may be achieved, especially in non-IgE-mediated allergies. However, some allergic manifestations persist, requiring treatment alternatives. Avoidance of the allergen and epinephrine application are key measures. Immunotherapy aims to desensitize immune cells, but its effectiveness varies. Bioterapeutic agents, such as monoclonal antibodies, are under investigation, although their clinical use still requires more studies.

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.

Eosinophil-Associated Gastrointestinal Manifestations During OIT

Gastrointestinal adverse events are common during oral immunotherapy (OIT) for food allergy and range from immediate IgE-mediated reactions to non-anaphylactic clinical presentations. This review aims to summarize recent findings on non-anaphylactic eosinophil-associated gastrointestinal adverse events during OIT. Two clinical presentations of non-anaphylactic eosinophil-associated gastrointestinal adverse events during OIT are identified, each with a different paradigm for treatment, and distinguished by their time of onset. In the first clinical entity, characterized by its onset early in the course of treatment, patients present with abdominal pain, nausea, and/or vomiting. The symptoms become evident typically within weeks to months of starting OIT. These symptoms, however, are not temporally related to the time of dose administration, as in the case of immediate IgE-mediated anaphylactic reactions. While esophageal biopsies, when performed, can demonstrate eosinophilic esophagitis (EoE), baseline esophageal eosinophilia has also been observed in food allergic patients prior to OIT. A potential non-invasive biomarker, the peripheral absolute eosinophil count (AEC), often rises during these reactions and subsides after dose reduction and subsequent resolution of symptoms. OIT can usually then be resumed, albeit at a slower pace, without a recurrence of symptoms. Risk factors for development of symptoms early during OIT include a high starting dose and a baseline AEC of greater than 600. The second, and much less frequently encountered, non-anaphylactic gastrointestinal adverse event related to OIT, presents months to years after initiating OIT. In this latter group, patients present with the classical clinical symptoms and endoscopic findings of EoE. In contrast to the acute onset group, peripheral eosinophilia is usually not observed in these cases. This OIT-associated EoE has shown good response to standard EoE treatment approaches of proton pump inhibitors or swallowed steroids. Most patients with eosinophil-associated adverse reactions are able to continue OIT and remain desensitized. Treatment approaches depend on the specific subtype of these reactions and relate to the stages of OIT treatment.

Safety and effectiveness of the Canadian food ladders for children with IgE-mediated food allergies to cow's milk and/or egg

BACKGROUND

Food ladders are tools designed to facilitate home-based dietary advancement in children with food allergies through stepwise exposures to increasingly allergenic forms of milk and egg. Several studies have now documented safety and efficacy of food ladders. In 2021, we published a Canadian adaptation of the previously existing milk and egg ladders originating in Europe using foods more readily available/consumed in Canada. Our study adds to the growing body of evidence supporting food ladder use and provides safety and effectiveness data for our Canadian adaptation of the milk and egg ladders.

METHODS

Surveys were distributed to families of children using the Canadian Milk Ladder and/or the Canadian Egg Ladder at baseline, with follow up surveys at 3 months, 6 months, and 12 months. Data were analyzed using REDCap and descriptive and inferential statistics are presented.

RESULTS

One hundred and nine participants were started on milk/egg ladders between September 2020 and June 2022. 53 participants responded to follow up surveys. Only 2 of 53 (3.8%) participants reported receiving epinephrine during the study. Severe grade 4 reactions (defined according to the modified World Allergy Organization grading system) were not reported by any participants. Minor cutaneous adverse reactions were common, with about 71% (n = 10/14) of respondents reporting cutaneous adverse reactions by 1 year of food ladder use. An increasing proportion of participants could tolerate most foods from steps 2-4 foods after 3, 6, and 12 months of the food ladder compared to baseline.

CONCLUSION

The Canadian food ladders are safe tools for children with cow's milk and/or egg allergies, and participants tolerated a larger range of foods with food ladder use compared to baseline.

An update on recent developments and highlights in food allergy

While both the incidence and general awareness of food allergies is increasing, the variety and clinical availability of therapeutics remain limited. Therefore, investigations into the potential factors contributing to the development of food allergy (FA) and the mechanisms of natural tolerance or induced desensitization are required. In addition, a detailed understanding of the pathophysiology of food allergies is needed to generate compelling, enduring, and safe treatment options. New findings regarding the contribution of barrier function, the effect of emollient interventions, mechanisms of allergen recognition, and the contributions of specific immune cell subsets through rodent models and human clinical studies provide novel insights. With the first approved treatment for peanut allergy, the clinical management of FA is evolving toward less intensive, alternative approaches involving fixed doses, lower maintenance dose targets, coadministration of biologicals, adjuvants, and tolerance-inducing formulations. The ultimate goal is to improve immunotherapy and develop precision-based medicine via risk phenotyping allowing optimal treatment for each food-allergic patient.

Food Allergens: When Friends Become Foes-Caveats and Opportunities for Oral Immunotherapy Based on Deactivation Methods

Food allergies represent a serious health concern and, since the 1990s, they have risen gradually in high-income countries. Unfortunately, the problem is complex because genetic, epigenetic, and environmental factors may be collectively involved. Prevention and diagnoses have not yet evolved into efficacious therapies. Identification and control of allergens present in edible substances hold promise for multi-purpose biomedical approaches, including oral immunotherapy. This review highlights recent studies and methods to modify the otherwise innocuous native proteins in most subjects, and how oral treatments targeting immune responses could help cancel out the potential risks in hypersensitive individuals, especially children. We have focused on some physical methods that can easily be conducted, along with chemo-enzymatic modifications of allergens by means of peptides and phytochemicals in particular. The latter, accessible from naturally-occurring substances, provide an added value to hypoallergenic matrices employing vegetal wastes, a point where food chemistry meets sustainable goals as well.

Baked Milk and Baked Egg Survey: A Work Group Report of the AAAAI Adverse Reactions to Foods Committee

Most milk- and egg-allergic children can tolerate milk and egg in baked forms. Some allergists have extended the use of baked milk (BM) and baked egg (BE) to advocating for the stepwise introduction of small amounts of BM and BE to children who are reactive to larger amounts of BM and BE. Little is known about the practice of introducing BM and BE and existing barriers to this approach. The purpose of this study was to gather a current assessment of the implementation of BM and BE oral food challenges and diets for milk- and egg-allergic children. We conducted an electronic survey of North American Academy of Allergy, Asthma & Immunology members offering BM and BE introduction in 2021. The response rate was 10.1% of distributed surveys (72 of 711). Surveyed allergists had a similar approach to both BM and BE introduction. Demographic features of time in practice and region of practice were significantly associated with the odds of introducing BM and BE. A wide variety of tests and clinical features guided decisions. Some allergists determined BM and BE to be appropriate for home introduction and offered this for BM and BE more often than other foods. The use of BM and BE as a food for oral immunotherapy was endorsed by almost half of respondents. Less time in practice was the most significant factor associated with offering this approach. Published recipes were used and written information was widely provided to patients by most allergists. The wide practice variabilities reveal a need for more structured guidance about oral food challenges, in-office versus home procedures, and patient education.

Food Oral Immunotherapy: A Survey Among US Practicing Allergists Conducted as a AAAAI Leadership Institute Project and Work Group Report

BACKGROUND

Food oral immunotherapy (OIT) is an active form of treatment for food allergies. Although research in this area has been ongoing for many years, the first US Food and Drug Administration-approved product for peanut allergy treatment became available only in January 2020. Limited data exist on OIT services offered by physicians in the United States.

OBJECTIVE

This workgroup report was developed to evaluate OIT practices among allergists practicing in the United States.

METHODS

The authors developed an anonymous 15-question survey and was subsequently reviewed and approved by the American Academy of Allergy, Asthma & Immunology Practices, Diagnostics and Therapeutics Committee before distribution to the membership. The American Academy of Allergy, Asthma & Immunology electronically distributed the survey to a random sample of 780 members in November 2021. In addition to questions specific to food OIT, the survey included questions on demographics and professional characteristics of the responders.

RESULTS

A total of 78 members completed the survey, yielding a 10% response rate. Fifty percent of responders were offering OIT in their practice. There was a significant difference in experience in OIT originating from research trials in academic versus nonacademic centers. Generally, OIT practices were similar in both settings for the number of foods offered, the performance of oral food challenges before initiating treatment, the number of new patients to whom OIT was offered to per month, and age groups OIT to whom was offered. Almost all of the reported barriers to OIT were similar between settings: staff and time limitations, concerns about safety and anaphylaxis, the need for more education on how to perform, inadequate compensation, and that it was not a significant demand from patients. Clinic space limitations were significantly different and more prominent in academic settings.

CONCLUSIONS

Our survey revealed interesting trends in the practice of OIT across the United States, with some significant differences arising when academic and nonacademic settings were compared.

Update on clinical research for food allergy treatment

The incidence of IgE-mediated food allergy (FA) has continued to increase over the years which places substantial burden on patient health and quality of life. With no cure for this disease, the mainstay of management has been allergen avoidance. However, there have been advancements in FA treatment in recent years with multiple clinical trials utilizing novel and innovative therapeutic strategies. A landmark event came in 2020 with the first drug approval for food allergy with the approval of a product for peanut oral immunotherapy. In addition to oral immunotherapy, different delivery systems of immunotherapy (SLIT, EPIT) are being studied in addition to probiotics, biologic agents - used as monotherapy and as an adjunct, and modified allergens has taken place with the hope to further enhance existing therapeutic options. The hope through these continued developments is for therapies to emerge that will provide a more comprehensive benefit to this patient population.

Double-Blind, Placebo-Controlled Study of E-B-FAHF-2 in Combination With Omalizumab-Facilitated Multiallergen Oral Immunotherapy

BACKGROUND

Oral immunotherapy (OIT) is limited by adverse events, and most patients require continued treatment to maintain their increased threshold. Adjunctive treatments have been explored to increase the safety and efficacy of OIT.

OBJECTIVE

This study aimed to determine the safety and efficacy of enhanced, butanol purified Food Allergy Herbal Formula-2 (E-B-FAHF-2) for inducing remission in subjects undergoing omalizumab-facilitated multiallergen OIT (multi-OIT).

METHODS

In this double-blind, placebo-controlled clinical trial, subjects were randomized 1:1 to receive either E-B-FAHF-2 or placebo, starting 2 months before OIT and continuing throughout OIT. All subjects received a 4-month course of omalizumab, starting 2 months before OIT through the 2-month OIT build-up phase. After 24 months of multi-OIT (maintenance dose of 1000 mg of each allergen), desensitization and remission were assessed. The primary objective was to determine if subjects in the E-B-FAHF-2 group (EOIT) were more likely than the placebo group (OIT) to develop remission to all 3 allergens treated with multi-OIT, as defined by the absence of dose-limiting symptoms to a cumulative dose of 4444 mg of protein after discontinuing treatment for 3 months.

RESULTS

Thirty-three subjects were randomized. A total of 63.6% were desensitized to 4444 mg of protein for each allergen at 26 months, and 24.2% met the primary outcome of remission at 29 months, with no difference between the treatment groups. There was good adherence (>85%) with study medications, with no difference between the treatment groups. There was no difference in reported overall adverse events between the treatment groups.

CONCLUSION

Omalizumab-facilitated multifood OIT was safe and effective, and remission was achieved in about a quarter of subjects. However, outcomes were not improved by the addition of E-B-FAHF-2.

Jak out of the box: Targeting Bruton's tyrosine kinase, sialic acid-binding immunoglobulin-like lectin-8, and Janus kinase 1 in food allergy

There has been rapid growth in the field of immunoglobulin E-mediated food allergy therapeutics, with 1 US Food and Drug Administration-approved therapy in 2020 and several others in various stages of investigation. Oral immunotherapy is the approach with the longest track record of study and provides desensitization for most individuals undertaking the therapy. However, the therapy must be maintained for continued clinical protection, and adverse effects of the therapy are frequent. There is a need to improve allergen immunotherapy safety and durability and to provide a treatment that can target multiple food allergies. In this review, we discuss novel adjunct therapies that may improve safety, such as omalizumab, Bruton's tyrosine kinase inhibitors, and agonists of sialic acid-binding immunoglobulin-like lectin-8, which suppress hypersensitivity responses. We also discuss approaches that may improve magnitude or durability of the treatment response, such as dupilumab and Janus kinase 1 inhibitors.

Are There Hidden Dangers Associated With Milk and Egg Dietary Advancement Therapy?

Dietary advancement therapies (DATs) constitute a continuum spanning extensively heated item ingestion, progressive milk or egg ladders, and oral immunotherapy (OIT). These represent an evolution in food allergy management from strict avoidance to an active therapy that may modulate the immune system to develop tolerance to particular forms of the allergen. Many egg or milk individuals are tolerant to baked egg or milk at baseline, and regular consumption (at home ingestion) of baked milk or egg is a safe process with potential quality of life and immunologic benefit. Milk and egg ladders, developed for non-IgE mediated allergy, are increasingly being adapted to IgE-mediated allergy as a potentially safe at-home option for gradual dietary advancement. However, data are limited regarding how safe and effective these approaches are or what patient is best suited for which DAT. It is also unclear whether extensively heated allergen consumption and ladders are susceptible to the same patient-specific factors that affect day-to-day tolerance and safety in OIT. Several recent events involving near-fatal or fatal reactions to milk or egg products (all among patients with asthma) have highlighted that DATs are not risk-free, and that physician guidance in these therapies is essential. Such guidance may include obtaining informed consent before starting any DAT and instituting the same safe dosing rules for OIT across any form of DAT. This rostrum discusses practical concerns about the safety of DAT, and considerations regarding how clinicians can maximize patient protection while defining the safety and efficacy of real-world implementation of these concepts.

Allergen recognition by specific effector Th2 cells enables IL-2-dependent activation of regulatory T-cell responses in humans

Type 2 allergen-specific T cells are essential for the induction and maintenance of allergies to foods, and Tregs specific for these allergens are assumed to be involved in their resolution. However, it has not been convincingly demonstrated whether allergen-specific Treg responses are responsible for the generation of oral tolerance in humans. We observed that sustained food allergen exposure in the form of oral immunotherapy resulted in increased frequency of Tregs only in individuals with lasting clinical tolerance. We sought to identify regulatory components of the CD4+ T-cell response to food allergens by studying their functional activation over time in vitro and in vivo. Two subsets of Tregs expressing CD137 or CD25/OX40 were identified with a delayed kinetics of activation compared with clonally enriched pathogenic effector Th2 cells. Treg activation was dependent on IL-2 derived from effector T cells. In vivo exposure to peanut in the form of an oral food challenge of allergic subjects induced a delayed and persistent activation of Tregs after initiation of the allergen-specific Th2 response. The novel finding of our work is that a sustained wave of Treg activation is induced by the release of IL-2 from Th2 effector cells, with the implication that therapeutic administration of IL-2 could improve current OIT approaches.

Oral Immunotherapy in Food Allergy: Where Are We Now?

Food allergy (FA) has become more prevalent and problematic in the last 2 decades, and it poses important individual, social, and economic burdens. Besides treating reactions induced by accidental exposure and periodic evaluation for acquiring natural tolerance, the primary management approach is still allergen avoidance as a global standard. However, an active therapeutic approach that can raise the reaction threshold or accelerate tolerance is needed. This review aimed to provide an overview and the latest evidence of oral immunotherapy (OIT), which has recently been used in the active treatment of FA. FA immunotherapy, particularly OIT, is gaining considerable interest, and substantial effort has been made to integrate this active treatment into clinical practice. Consequently, growing evidence has been obtained regarding the efficacy and safety of OIT, particularly for allergens such as peanuts, eggs, and milk. However, several issues need to be addressed regarding the availability, safety, and long-term effects of this intervention. In this review, we summarize currently available information regarding tolerance-inducing immune mechanisms of OIT, data on efficacy and safety, gaps in current evidence, and ongoing research to develop new therapeutic molecules in order to enhance safety.

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.

Retail Food Equivalents for Post-Oral Immunotherapy Dosing in the Omalizumab as Monotherapy and as Adjunct Therapy to Multi-Allergen Oral Immunotherapy in Food-Allergic Children and Adults (OUtMATCH) Clinical Trial

BACKGROUND

Patients with food allergy may be advised to introduce specific foods into their diets, both to increase tolerance gradually and as next steps after completing oral immunotherapy or other therapeutic interventions. However, the safe use of retail foods depends on the ability to establish the specific allergen protein content of these foods.

OBJECTIVE

To develop a systematic approach to estimate the protein content of peanut, milk, egg, wheat, cashew, hazelnut, and walnut in a variety of retail food equivalents for each allergen and associated patient education materials.

METHOD

We created an algorithm that used a multistep process with information from product food labels, nutrient databases, independent weighing and measuring of foods, and information provided by manufacturers, including certificates of analysis, and e-mail communication to estimate the allergen protein content of multiple retail foods for each of seven allergens. Once a variety of retail food equivalents for each allergen and allergen serving size was determined, we developed participant education handouts, which were reviewed by study teams at 10 food allergy centers, the National Institute of Allergy and Infectious Diseases, and the Consortium for Food Allergy Research coordinating center. After 1 year of use, multiple queries were addressed and the retail food equivalents and educational materials were reviewed and edited.

RESULTS

We identified a variety of retail food equivalents for seven allergens at six serving sizes, and created 48 unique patient education materials.

CONCLUSION

Our results provide extensive guidance on a variety of retail equivalents for seven foods, and a method to estimate retail food protein equivalents systematically with ongoing reassessment.

Treatment for food allergy: Current status and unmet needs

The treatment of food allergy has traditionally relied on avoidance of the offending food(s) and use of emergency medications in the event of accidental exposures. However, this long-standing paradigm is beginning to shift, as a variety of treatment approaches have been and are being developed. This report provides an overview of the past, present, and future landscape of interventional clinical trials for the treatment of food allergy. It focuses on specific issues related to participant characteristics, protocol design, and study end points in the key clinical trials in the literature and examine how differences between studies may impact the clinical significance of the study results. Recommendations are provided for the optimization of future trial designs and focus on specific unmet needs in this rapidly evolving field.

Home Introduction of Baked Egg After Oral Food Challenge

BACKGROUND

Baked egg (BE) introduction may accelerate resolution of egg allergy. Long-term data regarding the safety and success of BE introduction in the real world are limited.

OBJECTIVE

To identify predictors of future egg consumption and barriers to advancement based on characteristics during and after BE oral food challenges (OFCs).

METHODS

We performed a retrospective review of consecutive BE OFCs with a minimum 24-month follow-up. Goal doses ranged from 1/16 to 1/4 egg. Outcomes were categorized as pass (no reaction), fail (but allowed BE introduction), or fail (avoid). Status of egg introduction and reactions were recorded.

RESULTS

A total of 243 patients were included; 134 passed and 109 failed (70 of whom were instructed to introduce BE). At follow-up (median, 47 months), 90 (37%) were consuming direct egg, 26 (11%) lightly cooked egg, 39 (16%) BE, and 88 (36%) avoiding; 58% who failed versus 81% who passed were consuming some form of egg. Median egg white IgE level was significantly higher among avoiders versus introducers (8.7 vs 5.8; P = .008). Lower egg white IgE level and younger age were predictors of egg consumption in some form at follow-up (median IgE, 5.8 vs 8.4; P = .03; median age, 4.0 vs 8.0 years; P < .001). A total of 94 patients had a total of 136 reactions (132 mild, 4 severe); 22 (16.2%) were accidental exposures, 42 (30.9%) planned escalations, and 72 (52.9%) with previously tolerated doses.

CONCLUSIONS

Most patients who underwent a BE OFC continued to consume some form of egg, often advancing to direct egg. However, many reverted to avoidance and adverse reactions were common.

An overview of the current state of food desensitization

PURPOSE OF REVIEW

To highlight the current evidence on food desensitization in children with food allergy.

RECENT FINDINGS

Food Allergen Specific Immunotherapy (FA-AIT) is currently recognised as a treatment option for treating children with allergy at least to the main common foods (i.e. milk, egg and peanut). The oral route of administration has been proven to be the most effective in achieving desensitisation. Efforts are devoted to overcome the current unmet needs mainly related to safety issues and long-term efficacy, as well as adherence to the treatment and improvement of health-related quality of life. In this perspective, alternative routes of administration and adjunctive treatments are under investigation.

SUMMARY

The future of food allergy management is a personalised approach based on a shared decision-making that takes into account the needs of patients and families. Health professionals will be able to offer multiple treatment options, including FA-AIT with adjunctive or alternative therapies. Thus, patients should be correctly identified, using validated predictive factors, in order to select appropriate candidates for these therapies.

Information needs of patients considering oral immunotherapy for food allergy

While the historic management of food allergy includes avoidance strategies and allergic reaction treatment, oral immunotherapy (OIT) approaches have become more commonly integrated into therapeutic approaches. International guidelines, phase 3 trials and real-world experience have supported the implementation of this procedure. However, OIT is an elective, rarely curative procedure with inherent risks that necessitates an increased degree of health literacy for the patients and families. Families assume the responsibility of amateur healthcare providers to ensure the daily safe administration of the allergenic food. As such, it is incumbent upon physicians to ensure that families are prepared for this role. A thorough educational and shared decision-making approach is necessary during the counselling and consent process to adequately inform the families. Educated discussion about the efficacy and patient-centred effectiveness, therapeutic alternatives and family goals is required to align physician and patient expectations. A frank discussion about the struggles, practical challenges, risks and contraindications can help to develop an understanding of the risk mitigation strategies employed to maintain safety. Physicians should develop a proactive approach to educate families about this, at times, burdensome procedure. This educational approach should encourage ongoing support starting prior to consent through the maintenance visits. By preparing families for their unique management role, physicians can help ensure the safe and successful integration of OIT into the therapeutic offering for the management of food allergies.

Biomarkers in oral immunotherapy

Food allergy (FA) is a global health problem that affects a large population, and thus effective treatment is highly desirable. Oral immunotherapy (OIT) has been showing reasonable efficacy and favorable safety in most FA subjects. Dependable biomarkers are needed for treatment assessment and outcome prediction during OIT. Several immunological indicators have been used as biomarkers in OIT, such as skin prick tests, basophil and mast cell reactivity, T cell and B cell responses, allergen-specific antibody levels, and cytokines. Other novel indicators also could be potential biomarkers. In this review, we discuss and assess the application of various immunological indicators as biomarkers for OIT.

Long-term outcomes of oral immunotherapy for anaphylactic egg allergy in children

Background

Studies of long-term oral immunotherapy (OIT) in children with anaphylactic egg allergy are limited.

Objective

Our aim was to investigate the long-term outcomes of OIT for anaphylactic egg allergy.

Methods

The participants included children (aged ≥ 5 years) with a history of anaphylaxis in response to eggs and objective reactions to oral food challenge (OFC) with 250 mg of egg protein. In the OIT group, the home starting dose of egg protein set during 5 days of hospitalization was ingested once daily and gradually increased to 1000 mg. Over the next year, participants temporarily discontinued OIT for 2 weeks and underwent OFC with 3100 mg of egg protein annually until they passed. The historical control group comprised patients who did not receive OIT and repeated OFCs annually.

Results

In the OIT group (n = 20), the baseline median egg white- and ovomucoid-specific IgE levels were 45.5 and 38.5 kUA/L, respectively. The rate of passing OFC with 3100 mg of egg protein gradually increased in the OIT group, with rates of 20% at 1 year, 35% at 2 years, and 55% at 3 years, which were significantly higher than the rates in the historical control group at 3 years (5% [P < .001]). In the OIT group, 5 anaphylaxis events (0.04%) occurred at home, and 1 participant required intramuscular adrenaline. Furthermore, egg white- and ovomucoid-specific IgE levels decreased significantly after 3 years in both groups, whereas in the OIT group, these specific IgG and IgG4 levels increased significantly after a year.

Conclusion

Long-term OIT accelerated immunologic changes and enabled ingestion of 3100 mg of egg protein in half of the participants with anaphylactic egg allergy.

A practical focus on egg oral immunotherapy

Egg allergy usually develops in the first year of life, with an estimated prevalence of 2.6%-9%. Rates of resolution and timing vary, with approximately one-third of patients outgrowing their egg allergy by age 6 years. Persistent egg allergy has been associated with high egg white specific immunoglobulin E levels and sensitization to the egg allergen component Gal d 1, which is resistant to heat and digestion. These individuals seem to have a more severe and persistent phenotype of egg allergy. Recently, an active approach has emerged for patients with food allergy, including those with egg allergy, in the form of oral immunotherapy. Egg oral immunotherapy consists of the administration of gradually increasing doses of egg, with the aim to enable patients to consume small amounts of egg without having allergic reactions, which thus provides protection from accidental exposures to egg-containing foods. This article aims to discuss published evidence on egg oral immunotherapy, provide practical information on dosing protocols, and address special challenges associated with this intervention.

Variations in protocol development during oral immunotherapy

Oral immunotherapy (OIT) protocols are not standardized, and a wide heterogeneity exists in the literature. OIT protocol variables include the initiation approach (fixed dose versus oral food challenge), buildup speed (slow versus fast), target maintenance dose (low versus high target dose), type of food used, and use of adjuvants among other variables. Most protocols start with an initial escalation day, which is a series of extremely low doses to safely identify the patients who are most allergic, followed by a buildup period over several months to years until the final target maintenance dose is achieved. Doses are generally increased every 1-2 weeks by a factor of 1.25 to 2 and are adapted based on the patient's symptoms. Protocols are increasingly favoring low-maintenance doses over traditional high maintenance doses, although this needs to be discussed and adapted based on the patient's preferences. Accelerated OIT schedules with using a short treatment of omalizumab can be considered in severe food allergy cases.

Allergen-specific T cells and clinical features of food allergy: Lessons from CoFAR immunotherapy cohorts

BACKGROUND

Allergen-specific IL-4+ and IL-13+ CD4+ cells (type 2 cells) are essential for helping B cells to class-switch to IgE and establishing an allergic milieu in the gastrointestinal tract. The role of T cells in established food allergy is less clear.

OBJECTIVE

We examined the food allergen-specific T-cell response in participants of 2 food allergen immunotherapy trials to assess the relationship of the T-cell response to clinical phenotypes, including response to immunotherapy.

METHODS

Blood was obtained from 84 participants with peanut allergy and 142 participants with egg allergy who underwent double-blind placebo-controlled food challenges. Peanut- and egg-responsive T cells were identified by CD154 upregulation after stimulation with the respective extract. Intracellular cytokines and chemokine receptors were also detected. The response to peanut epicutaneous immunotherapy (Peanut Epicutaneous Phase II Immunotherapy Clinical Trial [CoFAR6]; 49 participants receiving epicutaneous immunotherapy) and egg oral immunotherapy or a baked egg diet (Baked Egg or Egg Oral Immunotherapy for Children With Egg Allergy [CoFAR7]; 92 participants) was monitored over time.

RESULTS

Peanut-specific type 2 and CCR6+ T cells were negatively correlated with each other and differently associated with immune parameters, including specific IgE level and basophil activation test result. At baseline, type 2 cells, but not CCR6+ cells, were predictive of clinical parameters, including a successfully consumed dose of peanut and baked egg tolerance. Exposure to peanut or egg immunotherapy was associated with a decrease in type 2 cell frequency. At baseline, high egg-specific type 2 cell frequency was the immune feature most predictive of oral immunotherapy failure.

CONCLUSION

Food-specific type 2 T cells at baseline are informative of threshold of reactivity and response to immunotherapy.

The year in food allergy

Research into food allergy continues to rapidly evolve, accompanying and driving real changes in the clinical approach to these diseases. The past year has seen the rollout of the first treatment approved for active management of food allergy, more data on alternative methods of treatment, the continued evolution of strategies for prevention of food allergy, a renewed interest in phenotyping food allergy subtypes, and, importantly, key new insights into the pathophysiology of food allergy. We expect that in the coming years, the therapies that are in preclinical or early clinical evaluation now will make their way to the clinic, finally allowing the possibility of safe and effective treatments for food allergy.

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.

Bringing the Next Generation of Food Allergy Diagnostics into the Clinic

Food allergy diagnosis has a massive impact on the lives of patients and their families. Despite recent developments with specific IgE to component allergens, a significant proportion of patients assessed for possible food allergy require oral food challenge to ensure an accurate diagnosis. More precise diagnostic methods are required to reduce the need for oral food challenges. Bead-based epitope assays and cellular tests, such as basophil activation and mast cell tests are the most novel and promising tests on the horizon. There is a pathway to pursue to enable their incorporation in clinical practice, including standardization, technical validation, clinical validation, external validation, overcoming practical and logistical issues, and regulatory approval. Valuable clinical application of these tests goes beyond diagnosis and includes risk assessment to identify allergic patients who are most sensitive and at risk for severe allergic reactions, and to define prognosis and assess clinical response to immunomodulatory treatments.

Home-Based Up-Dosing in Build-Up Phase of Oral Immunotherapy of Egg Allergy Is Safe and Feasible in Real-World Practice

Oral immunotherapy (OIT) has emerged to build sustained unresponsiveness or tolerance in patients with egg allergy. However, it is important to increase compliance and ensure safety because OIT requires an extended period of time and has a risk of side effects like anaphylaxis. We aimed to show the feasibility and safety of OIT during the build-up phase using a home-based, up-dosing method in children with egg allergy. Sixteen patients aged 4 to 12 years with egg allergy were enrolled. Patients increased the dose of boiled egg white (EW) by 5% per day at home and 25% per month at the hospital, with a target dose of 40 g of boiled EW (4.0 g of EW proteins). A historical control group (n = 16) was matched for age, sex, and clinical characteristics for comparisons with the OIT group. Oral food challenge (OFC) tests were performed after completing the build-up phase. In the OIT group, 93.8% (15/16) of patients achieved desensitization, with only 1 patient discontinuing OIT before the maintenance phase due to repeated allergic reactions. Mild allergic reactions and anaphylaxis occurred in 12 (75.0%) and 2 patients (12.5%), respectively. However, there were no significant adverse reactions such as serious anxiety or life-threatening events that required discontinuation of treatment. On the contrary, only 1 patient (6.3%) in the control group passed an OFC of 40 g of boiled EW during the same period (P < 0.001). Our results suggest that home-based up-dosing protocols using boiled eggs may be safe and feasible for the build-up phase of OIT in children with egg allergy.

Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis

Regional and national legislation mandates the disclosure of “priority” allergens when present as an ingredient in foods, but this does not extend to the unintended presence of allergens due to shared production facilities. This has resulted in a proliferation of precautionary allergen (“may contain”) labels (PAL) that are frequently ignored by food-allergic consumers. Attempts have been made to improve allergen risk management to better inform the use of PAL, but a lack of consensus has led to variety of regulatory approaches and nonuniformity in the use of PAL by food businesses. One potential solution would be to establish internationally agreed “reference doses,” below which no PAL would be needed. However, if reference doses are to be used to inform the need for PAL, then it is essential to characterize the hazard associated with these low-level exposures. For peanut, there are now published data relating to over 3000 double-blind, placebo-controlled challenges in allergic individuals, but a similar level of evidence is lacking for other priority allergens. We present the results of a rapid evidence assessment and meta-analysis for the risk of anaphylaxis to a low-level allergen exposure for priority allergens. On the basis of this analysis, we propose that peanut can and should be considered an exemplar allergen for the hazard characterization at a low-level allergen exposure.

Addressing Common Misconceptions in Food Allergy: A Review

Background: Food allergies are common, affecting 1 in 13 school children in the United States and their prevalence is increasing. Many misconceptions exist with regards to food allergy prevention, diagnosis and management. Objective: The main objective of this review is to address misconceptions with regards to food allergies and discuss the optimal, evidence-based approach for patients who carry this diagnosis. Observations: Common misconceptions in terms of food allergy prevention include beliefs that breastfeeding and delayed introduction of allergenic foods prevent the development of food allergies. In terms of diagnosis, statements such as ‘larger skin prick tests or/and higher levels of food-specific IgE can predict the severity of food-induced allergic reactions’, or ‘Tryptase is always elevated in food-induced anaphylaxis’ are inaccurate. Additionally, egg allergy is not a contraindication for receiving the influenza vaccine, food-allergy related fatalities are rare and peanut oral immunotherapy, despite reported benefits, is not a cure for food allergies. Finally, not all infants with eczema will develop food allergies and epinephrine auto-injectors may unfortunately be both unavailable and underused in food-triggered anaphylaxis. Conclusions and relevance: Healthcare professionals must be familiar with recent evidence in the food allergy field and avoid common misunderstandings that may negatively affect prevention, diagnosis and management of this chronic disease.