AR101 Oral Immunotherapy for Peanut Allergy

AAAAI-EAACI PRACTALL: Standardizing oral food challenges-2024 Update

This common statement of the American Academy of Allergy, Asthma and Immunology (AAAAI) and The European Academy of Allergy and Clinical Immunology (EAACI) provides an update of the 2012 published guidelines on food challenges. The guidelines equally address food challenges in the research and the clinical settings. They first address the diagnostic tests which can guide the decision to conduct a challenge. Safety of food challenges is prime, and the various procedures and safety issues as well as medications potentially involved in challenges are extensively discussed. Challenges are suggested to be conducted with semi-logarithmic incremental doses based on the protein content, typically for IgE-mediated food allergy with intervals of 20-30 min between doses. Specific protocols for other types of reactions such atopic dermatitis or gastrointestinal food allergy are detailed separately. Proper stopping criteria are essential in order to reduce the risk of false-positive diagnoses, but also severe reactions. The guidelines recommend criteria based on "go on," "stop," or "observation." These revised guidelines will clearly provide much needed guidance for food challenges in the research and clinical settings. They will continue to evolve with new diagnostic tests or new needs in the field of food allergy.

Prevalence and Characteristics of Accidental Ingestions Among Pediatric Food Allergy Patients

BACKGROUND

Despite a known diagnosis of food allergy, accidental ingestions continue to occur.

OBJECTIVE

To characterize accidental ingestions, including prevalence, risk factors, food allergen triggers, and severity of reactions.

METHODS

A prospective monthly survey developed by the Food Allergy Consortium at Northwestern University was administered to parents of food-allergic children between April 2015 and April 2017. The monthly survey included questions on any allergic reactions experienced in the previous month. In addition, chart reviews of 100 pediatric participants from Lurie Children's Hospital of Chicago allergy clinics (typical clinical encounters) were compared with the prospective survey results.

RESULTS

A total of 196 survey participants and 100 retrospective review subjects were analyzed-31.1% of participants from the surveyed cohort and 19.0% of participants from the retrospective review reported at least 1 accidental ingestion over 1 year. The rate of accidental ingestions reported in the prospective survey was high: 10% to 25% of participants each month reported an accidental ingestion, and multiple ingestions were common. Common triggers were milk, wheat, and tree nuts. In the retrospective cohort, the highest rate of accidental ingestion (25.0%) occurred for milk, followed by sesame (20.0%) and egg (18.8%). Rates of anaphylaxis after exposure were high in both the prospective and retrospective cohorts (33.1% and 16.7%, respectively).

CONCLUSIONS

Accidental ingestion rates were high among food-allergic patients. Multiple exposures, especially to milk, were common. Incidence of anaphylaxis was also high, suggesting that ongoing patient education on allergen avoidance and accidental exposure is imperative.

Differences in familiarity with oral immunotherapy among caregivers of White and Black children with food allergy

BACKGROUND

Potential racial and ethnic disparities related to oral immunotherapy (OIT) have not been fully described among children with food allergy (FA).

OBJECTIVE

To characterize the differences in attitudes toward, familiarity with, and utilization of OIT among non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic or Latino (H/L) caregivers of children with FA.

METHODS

Surveys were administered to the caregivers of children enrolled in Food Allergy Outcomes Related to White and African American Racial Differences, a prospective, multisite cohort of children with FA. The distribution of responses by caregiver-reported race and ethnicity was described using an analysis of variance for continuous outcomes and χ2 tests for categorical outcomes. A logistic regression model was used to determine associations between familiarity with OIT as a treatment option and various other covariates.

RESULTS

The NHB and H/L respondents were more frequently not familiar with OIT compared with NHW responders (54.3% and 62.5% vs 9.2%, P < .001). This finding remained true, even after adjusting for household income (odds ratio: 0.1, 95% CI: 0.1-0.4 for NHB participants and odds ratio: 0.1, 95% CI: 0.0-0.3 for H/L participants). NHB and H/L participants more frequently reported that they had never heard of OIT before the survey compared with NHW participants (76.7% and 50.0% vs 26.7%, P < .001). None of the NHB and H/L respondents initiated OIT compared with 14.8% of NHW participants (P < .001).

CONCLUSION

In the Food Allergy Outcomes Related to White and African American Racial Differences cohort, familiarity with OIT was lower among caregivers of minoritized racial and ethnic groups, even after adjusting for household income.

Real-world experience: a retrospective pediatric chart review to determine why patients and caregivers discontinue oral immunotherapy

BACKGROUND

Oral immunotherapy (OIT) is an increasingly utilized management strategy for IgE-mediated food allergy. Despite promising efficacy and effectiveness, there is still a lack of data surrounding the reasons for discontinuation of OIT. The primary reason stated in the literature for discontinuation is adverse gastrointestinal effects. Social factors contributing to OIT discontinuation have not been well reported. We hypothesize that social considerations are significant contributors to treatment discontinuation.

METHODS

We completed a retrospective chart review of 50 patients treated in community pediatric allergy practices who discontinued OIT out of 507 patients who were started on OIT between October 1, 2017-October 27, 2022. Reasons for discontinuation were identified and classified into five main categories: unsafe care decisions, anxiety, adverse effects of OIT, uncontrolled comorbidity and social factors. Categories were not exclusive.

RESULTS

507 patients were started on OIT, with data available for 50 patients who discontinued OIT, aged 10 months to 18 years and 2 months. The overall discontinuation rate was 9.8%, of which 40 patients (80%) discontinued during buildup, 9 patients (18%) discontinued during maintenance and one patient on two food OIT discontinued one food during buildup and one during maintenance (2%). Thirty-four patients (68%) had multiple reasons for discontinuing OIT. Social factors were the most common reason for discontinuation and were identified in 32 patients (64%). Twenty-four patients (48%) discontinued OIT due to adverse effects. Gastrointestinal symptoms were the most prevalent, while anaphylaxis contributed to discontinuation in 15 patients (30%). Anxiety led to discontinuation in 17 patients (34%).

CONCLUSIONS

Our data highlights the importance of social factors and anxiety in the success of OIT completion. Our results support the need to consider not only the patient's medical history, but also their social history and support networks when selecting patients who are good candidates for OIT to optimize the successful completion of OIT.

Peanut Allergy in Children-Is Prevention Better than Cure?

Peanut allergy, one of the most frequently occurring allergies, usually starts in childhood and rarely subsides-often persisting throughout adult life. Accidental exposure to peanuts can often result in adverse reactions ranging from mild to life-threatening, such as anaphylactic shock. Historically, food avoidance and the use of rescue drugs have remained a fundamental management mechanism for dealing with food allergy. However, prevention of adverse reactions to food allergy is playing an increasing role. This is possible through the early introduction of peanuts into the diet, especially in infants at risk of this allergy. In recent years, specific immunotherapy has been used to develop desensitisation and, in some patients, tolerance-defined as a persistent state of clinical non-reactivity to the allergen after therapy is finished. The aim of this article is to summarise the current state of knowledge on the prevention and treatment of peanut allergy, with a focus on clinical trials, current guidelines, and recent experimental studies. This review may be particularly useful for paediatricians and general practitioners.

Insights into the clinical, immunologic, and genetic underpinnings of food allergy

The last few decades have seen striking changes in the field of food allergy. The prevalence of the disease has risen dramatically in many parts of the globe, and management of the condition has undergone major revision. While delayed introduction of common allergenic foods during infancy was advised for many years, the learning early about peanut allergy (LEAP) trial and other studies led to a major shift in infant feeding practices, with deliberate early introduction of these foods now recommended. Additionally, the Food and Drug Administration approved the first treatment for food allergy in 2020-a peanut oral immunotherapy (OIT) product that likely represents just the beginning of new immunotherapy-based and other treatments for food allergy. Our knowledge of the environmental and genetic factors contributing to the pathogenesis of food allergy has also undergone transformational advances. Here, we will discuss our efforts to improve the clinical care of patients with food allergy and our understanding of the immunological mechanisms contributing to this common disease.

Mechanisms for initiation of food allergy by skin pre-disposed to atopic dermatitis

Food allergy can be life-threatening and often develops early in life. In infants and children, loss-of-function mutations in skin barrier genes associate with food allergy. In a mouse model with skin barrier mutations (Flakey Tail, FT+/- mice), topical epicutaneous sensitization to a food allergen peanut extract (PNE), an environmental allergen Alternaria alternata (Alt) and a detergent induce food allergy and then an oral PNE-challenge induces anaphylaxis. Exposures to these allergens and detergents can occur for infants and children in a household setting. From the clinical and preclinical studies of neonates and children with skin barrier mutations, early oral exposure to allergenic foods before skin sensitization may induce tolerance to food allergens and thus protect against development of food allergy. In the FT+/- mice, oral food allergen prior to skin sensitization induce tolerance to food allergens. However, when the skin of FT+/- pups are exposed to a ubiquitous environmental allergen at the time of oral consumption of food allergens, this blocks the induction of tolerance to the food allergen and the mice can then be skin sensitized with the food allergen. The development of food allergy in neonatal FT+/- mice is mediated by altered skin responses to allergens with increases in skin expression of interleukin 33, oncostatin M and amphiregulin. The development of neonate food allergy is enhanced when born to an allergic mother, but it is inhibited by maternal supplementation with α-tocopherol. Moreover, preclinical studies suggest that food allergen skin sensitization can occur before manifestation of clinical features of atopic dermatitis. Thus, these parameters may impact design of clinical studies for food allergy, when stratifying individuals by loss of skin barrier function or maternal atopy before offspring development of atopic dermatitis.

Regulation of immune responses to food by commensal microbes

The increasing prevalence of immune-mediated non-communicable chronic diseases, such as food allergies, has prompted a deeper investigation into the role of the gut microbiome in modulating immune responses. Here, we explore the complex interactions between commensal microbes and the host immune system, highlighting the critical role of gut bacteria in maintaining immune homeostasis. We examine how modern lifestyle practices and environmental factors have disrupted co-evolved host-microbe interactions and discuss how changes in microbiome composition impact epithelial barrier function, responses to food allergens, and susceptibility to allergic diseases. Finally, we examine the potential of bioengineered microbiome-based therapies, and live biotherapeutic products, for reestablishing immune homeostasis to prevent or treat food allergies.

Saliva antibody profiles are associated with reaction threshold and severity of peanut allergic reactions

BACKGROUND

Reaction threshold and severity in food allergy are difficult to predict, and noninvasive predictors are lacking.

OBJECTIVE

We sought to determine the relationships between pre-challenge levels of peanut (PN)-specific antibodies in saliva and reaction threshold, severity, and organ-specific symptoms during PN allergic reactions.

METHODS

We measured PN-specific antibody levels in saliva collected from 127 children with suspected PN allergy before double-blind, placebo-controlled PN challenges in which reaction threshold, severity, and symptoms were rigorously characterized. Low threshold (LT) PN allergy was defined as reaction to <300 mg of PN protein cumulatively consumed. A consensus severity grading system was used to grade severity. We analyzed associations between antibody levels and reaction threshold, severity, and organ-specific symptoms.

RESULTS

Among the 127 children, those with high pre-challenge saliva PN IgE had higher odds of LT PN allergy (odds ratio [OR] 3.9, 95% CI 1.6-9.5), while those with high saliva PN IgA:PN IgE ratio or PN IgG4:PN IgE ratio had lower odds of LT PN allergy (OR 0.3, 95% CI 0.1-0.8; OR 0.4, 95% CI 0.2-0.9). Children with high pre-challenge saliva PN IgG4 had lower odds of severe PN reactions (OR 0.4, 95% CI 0.2-0.9). Children with high saliva PN IgE had higher odds of respiratory symptoms (OR 8.0, 95% CI 2.2-26.8). Saliva PN IgE modestly correlated with serum PN IgE levels (Pearson r = 0.31, P = .0004). High and low saliva PN IgE levels further distinguished reaction threshold and severity in participants stratified by serum PN IgE, suggesting endotypes.

CONCLUSIONS

Saliva PN antibodies could aid in noninvasive risk stratification of PN allergy threshold, severity, and organ-specific symptoms.

Contribution of T cell subsets to different food allergic diseases

Food allergies occur due to a lack of tolerance to the proteins found in foods. While IgE- and non-IgE-mediated food allergies have different clinical manifestations, epidemiology, pathophysiology, and management, they share dysregulated T cell responses. Recent studies have shed light on the contributions of different T cell subsets to the development and persistence of different food allergic diseases. This review discusses the role of T cells in both IgE- and non-IgE-mediated food allergies and considers the potential future investigations in this context.

Peanut allergen characterization and allergenicity throughout development

Introduction

Peanut allergy (PA) in children is a major concern. There is a need for better biological material for both diagnosis and oral immunotherapy (OIT) treatments. The unique state of seeds at early reproductive stages may affect the allergenicity of storage proteins, and impact clinical diagnostic and OIT protocols. The objective of this study was to evaluate the major allergen content in sequential seed developmental stages and monitor allergenicity via specific IgE binding quantification and skin prick testing.

Methods

Seeds were collected from peanut plants and sorted into five developmental stages: initial (S1), developing (S2), full-size without coloration (S3), full-size with coloration (S4), and fully mature (S5) seeds. Samples were characterized by RNA-Seq, ELISA, and immunohistochemistry. Lyophilized, ground preparations were used for evaluation of skin test responses in sixty challenge-proven PA children.

Results

Gene expression, protein content, and specific IgE binding of allergenic proteins increased throughout seed maturation and development. An expression bias towards the less allergenic A-genome copy of the major allergen Ara h 2 was found in earlier stages, especially in stage S2. Immunohistochemical staining showed that Ara h 2 is more dispersed in the cell and less accumulated within organized bodies at stage S2 versus stage S4. Significant differences were found in mean wheal responses between the commercial peanut extract (equivalent to stage S5) and stages S1 and S2, but not with stage S4, upon skin prick testing in subjects with PA.

Discussion

The observed decrease in peanut-specific IgE binding of immature peanut seeds may be a result not only of decreased amounts of allergenic proteins, but also of profound changes in seed composition and conformation. This may be significant for developing a safer and more effective peanut OIT protocol.

Addressing common questions on food oral immunotherapy: a practical guide for paediatricians

Food allergy has been increasing in prevalence in most westernised countries and poses a significant burden to patients and families; dietary and social limitations as well as psychosocial and economic burden affect daily activities, resulting in decreased quality of life. Food oral immunotherapy (food-OIT) has emerged as an active form of treatment, with multiple benefits such as increasing the threshold of reactivity to the allergenic food, decreasing reaction severity on accidental exposures, expanding dietary choices, reducing anxiety and generally improving quality of life. Risks associated with food immunotherapy mostly consist of allergic reactions during therapy. While the therapy is generally considered both safe and effective, patients and families must be informed of the aforementioned risks, understand them, and be willing to accept and hedge these risks as being worthwhile and outweighed by the anticipated benefits through a process of shared decision-making. Food-OIT is a good example of a preference-sensitive care paradigm, given candidates for this therapy must consider multiple trade-offs for what is considered an optional therapy for food allergy compared with avoidance. Additionally, clinicians who discuss OIT should remain increasingly aware of the growing impact of social media on medical decision-making and be prepared to counter misconceptions by providing clear evidence-based information during in-person encounters, on their website, and through printed information that families can take home and review.

DNA Meets Protein─Development, Characterization, and Application of Aptamers against Peanut Allergen

Allergen detection methods support food labeling and quality assessment at the allergen component level of allergen preparations used for allergy diagnosis and immunotherapy (AIT). Commonly applied enzyme-linked immunosorbent assay (ELISA) requires animal antibodies but potentially shows batch variations. We developed synthetic aptamers as alternative binders in allergen detection to meet the replacement, reduction, and refinement (3R) principle on animal protection in science. ssDNA aptamers were specifically selected against the major peanut allergen Ara h 1 and identified by next-generation sequencing. Application in various detection systems (ELISA-like assays, western blot, and surface plasmon resonance) was demonstrated. The ELISA-like assay comprised a sensitivity of 10 ng/mL Ara h 1, comparable to published antibody-based ELISA, and allowed Ara h 1 detection in various peanut flours, similar to those used in peanut AIT as well as in processed food. This ELISA-like aptamer-based assay proofs antibody-free allergen detection for food labeling or quality assessment of diagnostic and therapeutic allergen products.

Immunotherapy with biodegradable nanoparticles encapsulating the oligosaccharide galactose-alpha-1,3-galactose enhance immune tolerance against alpha-gal sensitization in a murine model of alpha-gal syndrome

IgE antibodies against the mammalian oligosaccharide allergen galactose-α-1,3-galactose (αGal) can result in a severe allergic disease known as alpha-gal syndrome (AGS). This syndrome, acquired by tick bites that cause αGal sensitization, leads to allergic reactions after ingestion of non-primate mammalian meat and mammalian-derived products that contain αGal. Allergen-specific immunotherapies for this tickborne allergic syndrome are understudied, as are the immune mechanisms of allergic desensitization that induce clinical tolerance to αGal. Here, we reveal that prophylactic administration of αGal glycoprotein-containing nanoparticles to mice prior to tick protein-induced αGal IgE sensitization blunts the production of Th2 cytokines IL-4, IL-5, and IL-13 in an αGal-dependent manner. Furthermore, these effects correlated with suppressed production of αGal-specific IgE and hypersensitivity reactions, as measured by reduced basophil activation and histamine release and the systemic release of mast cell protease-1 (MCPT-1). Therapeutic administration of two doses of αGal-containing nanoparticles to mice sensitized to αGal had partial efficacy by reducing the Th2 cytokine production, αGal-specific IgE production, and MCPT-1 release without reducing basophil activation or histamine release. These data identify nanoparticles carrying encapsulated αGal glycoprotein as a potential strategy for augmenting αGal-specific immune tolerance and reveal diverse mechanisms by which αGal nanoparticles modify immune responses for established αGal-specific IgE-mediated allergic reactions.

Navigating the landscape of food allergies: Insights and perspectives from the AMCP Market Insights Program

AMCP convened a panel of clinical and managed care experts to identify insights regarding the prevalence, clinical manifestations, and management approaches for immunoglobulin E-mediated food allergies. This article aims to summarize expert perspectives on health care system challenges and areas of agreement concerning the management of food allergies, and to advance payers' understanding of their role in supporting health care for patients with food allergies. Food allergy management requires dietary modification and is associated with significant patient and caregiver burdens. Emerging therapies provide hope for those living with food allergies but will likely lead to a rise in health plan pharmacy expenses. In considering the value of new treatments, it is important to consider the total cost of care and the value of preventing anaphylaxis and enhancing the patient's quality of life. Several challenges remain in identifying the appropriate patient population for treatment with newer agents and in optimizing treatment outcomes. Addressing health disparities will require standardized clinical protocols, better access to specialized allergy care, and management of comorbid conditions.

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.

Enhanced Gut Microbiome Capacity for Amino Acid Metabolism is associated with Peanut Oral Immunotherapy Failure

Peanut Oral Immunotherapy (POIT) holds promise for remission of peanut allergy, though treatment is protracted and successful in only a subset of patients. Because the gut microbiome is linked to food allergy, we sought to identify fecal microbial predictors of POIT efficacy and to develop mechanistic insights into treatment response. Longitudinal functional analysis of the fecal microbiome of children (n=79) undergoing POIT in a first double-blind, placebo-controlled clinical trial, identified five microbial-derived bile acids enriched in fecal samples prior to POIT initiation that predicted treatment efficacy (AUC 0.71). Failure to induce disease remission was associated with a distinct fecal microbiome with enhanced capacity for bile acid deconjugation, amino acid metabolism, and increased peanut peptide degradation in vitro . Thus, microbiome mechanisms of POIT failure appear to include depletion of immunomodulatory secondary bile and amino acids and the antigenic peanut peptides necessary to promote peanut allergy desensitization and remission.

Age-Related Food Aversion and Anxiety Represent Primary Patient Barriers to Food Oral Immunotherapy

BACKGROUND

Although oral immunotherapy (OIT) for food allergy is a reasonable treatment option, barriers to this procedure's implementation have not been extensively evaluated from a patient perspective.

OBJECTIVE

We evaluated the barriers patients face during OIT administration, including anxiety and taste aversion, and the role of health care professionals, especially dietitians.

METHODS

A survey in Canada and the United States involved families currently enrolled in food OIT programs.

RESULTS

Of responses from 379 participants, fear of reaction was the most common barrier to OIT initiation, with 45.6% reporting it being a "very significant" barrier with other fears reported. However, taste aversion represented the prominent obstacle to continuation. Taste aversion was associated with a slower buildup (P = .02) and a reduction in dose (P = .002). Taste aversion was a strongly age-dependent barrier for initiation (P < .001) and continuation (P < .002), with older children over 6 years of age reporting it as a very significant barrier (P < .001). Boredom was reported as a concern for specific allergens such as peanut, egg, sesame, and hazelnuts (P < .05), emphasizing the need for diverse food options. Notably, 59.9% of respondents mixed OIT foods with sweet items. Despite these dietary concerns, dietitians were underutilized, with only 9.5% of respondents having seen a dietitian and the majority finding dietitian support helpful with greater certainty about the exact dose (P < .001).

CONCLUSIONS

Taste aversion and anxiety represent primary patient-related barriers to OIT. Taste aversion was highly age dependent, with older patients being more affected. Dietitians and psychology support were underutilized, representing a critical target to improve adherence and OIT success.

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 and Modification of a Shared Decision-Making Tool for Peanut Allergy Management

PURPOSE OF REVIEW

Based on shared decision-making (SDM) principles, a decision aid was previously developed to help patients, their caregivers, and physicians decide which peanut allergy management approach best suits them. This study refined the decision aid's content to better reflect patients' and caregivers' lived experience.

RECENT FINDINGS

Current standard of care for peanut allergy is avoidance, although peanut oral immunotherapy has been approved by the Food and Drug Administration for use in patients 4-17 years old. An advisory board of allergy therapy experts (n = 3) and patient advocates (n = 3) informed modifications to the decision aid. The revised tool underwent cognitive debriefing interviews (CDIs) among adolescents (12-17 years old) with peanut allergy and caregivers of patients 4-17 years old with peanut allergy to evaluate its relevance, understandability, and usefulness. The 20 CDI participants understood the information presented in the SDM tool and reported it was important and relevant. Some revisions were made based on participant feedback. Results support content validity of the Peanut Allergy Treatment SDM Tool.

Preparing Patients for Oral Immunotherapy (PPOINT): International Delphi consensus for procedural preparation and consent

BACKGROUND

Despite the promise of oral immunotherapy (OIT) to treat food allergies, this procedure is associated with potential risk. There is no current agreement about what elements should be included in the preparatory or consent process.

OBJECTIVE

We developed consensus recommendations about the OIT process considerations and patient-specific factors that should be addressed before initiating OIT and developed a consensus OIT consent process and information form.

METHODS

We convened a 36-member Preparing Patients for Oral Immunotherapy (PPOINT) panel of allergy experts to develop a consensus OIT patient preparation, informed consent process, and framework form. Consensus for themes and statements was reached using Delphi methodology, and the consent information form was developed.

RESULTS

The expert panel reached consensus for 4 themes and 103 statements specific to OIT preparatory procedures, of which 76 statements reached consensus for inclusion specific to the following themes: general considerations for counseling patients about OIT; patient- and family-specific factors that should be addressed before initiating OIT and during OIT; indications for initiating OIT; and potential contraindications and precautions for OIT. The panel reached consensus on 9 OIT consent form themes: benefits, risks, outcomes, alternatives, risk mitigation, difficulties/challenges, discontinuation, office policies, and long-term management. From these themes, 219 statements were proposed, of which 189 reached consensus, and 71 were included on the consent information form.

CONCLUSION

We developed consensus recommendations to prepare and counsel patients for safe and effective OIT in clinical practice with evidence-based risk mitigation. Adoption of these recommendations may help standardize clinical care and improve patient outcomes and quality of life.

Follow-up to Adolescence after Early Peanut Introduction for Allergy Prevention

BACKGROUND

A randomized trial demonstrated consumption of peanut from infancy to age 5 years prevented the development of peanut allergy. An extension of that trial demonstrated the effect persisted after 1 year of peanut avoidance. This follow-up trial examined the durability of peanut tolerance at age 144 months after years of ad libitum peanut consumption.

METHODS

Participants from a randomized peanut consumption trial were assessed for peanut allergy following an extended period of eating or avoiding peanuts as desired. The primary end point was the rate of peanut allergy at age 144 months.

RESULTS

We enrolled 508 of the original 640 participants (79.4%); 497 had complete primary end point data. At age 144 months, peanut allergy remained significantly more prevalent in participants in the original peanut avoidance group than in the original peanut consumption group (15.4% [38 of 246 participants] vs. 4.4% [11 of 251 participants]; P<0.001). Participants in both groups reported avoiding peanuts for prolonged periods of time between 72 and 144 months. Participants at 144 months in the peanut consumption group had levels of Ara h2-specific immunoglobulin E (a peanut allergen associated with anaphylaxis) of 0.03 ± 3.42 kU/l and levels of peanut-specific immunoglobulin G4 of 535.5 ± 4.98 μg/l, whereas participants in the peanut avoidance group had levels of Ara h2-specific immunoglobulin E of 0.06 ± 11.21 kU/l and levels of peanut-specific immunoglobulin G4 of 209.3 ± 3.84 μg/l. Adverse events were uncommon, and the majority were related to the food challenge.

CONCLUSIONS

Peanut consumption, starting in infancy and continuing to age 5 years, provided lasting tolerance to peanut into adolescence irrespective of subsequent peanut consumption, demonstrating that long-term prevention and tolerance can be achieved in food allergy. (Funded by the National Institute of Allergy and Infectious Diseases and others; ITN070AD, ClinicalTrials.gov number, NCT03546413.).

Sublingual immunotherapy for allergy to shrimp: the nine-year clinical experience of a Midwest Allergy-Immunology practice

BACKGROUND

Diet restrictions and fear of adverse reactions put a significant burden on the nutrition, growth and life style of children and adults with food allergies. While various disease-modifying options are pursued, there are so far no published clinical data on immunotherapy for crustaceans. The efficacy and safety of desensitization to crustaceans by means of sublingual immunotherapy is assessed for the first time in this study with a view of validating it as a clinical-practice modality.

METHODS

Charts of a Midwest Allergy-Immunology practice from the period January 2014-June 2023 were reviewed to identify patients with allergy to shrimp treated with sublingual immunotherapy and to retrospectively evaluate their responses to oral challenge.

RESULTS

Sixty-six patients were identified who had been treated by sublingual immunotherapy for either systemic or localized reactions to shrimp. Demographics and relevant comorbidities were consistent with those of the atopic population. Sublingual immunotherapy with serially diluted mixtures was initiated at 64-320 ng/dose and was gradually escalated to 0.5 mg/dose three times a day. The sublingual immunotherapy course ranged from 5 to 72 months (average: 51 months), following which, 18 patients underwent shrimp oral challenge. No systemic reactions occurred upon challenge; no patient required epinephrine. Tolerance of target dose equal to or exceeding 42 g shrimp was achieved in 11 patients (61%), seven of whom had originally presented with systemic reactions to crustaceans. Seven patients (38%) developed one or more of the following localized reactions: oral itching, nasal symptoms, localized perioral hives, localized hives at pressure points, nausea, vomiting, abdominal pain upon exposure to a cumulative dose of 39.2-148.2 g of shrimp during the 4 h of the challenge. Five of these patients had originally presented with systemic reactions to crustaceans. Five of the 7 patients who developed localized symptoms during the challenge were subsequently placed on routine exposure to 12-20 g shrimp every other day. Two patients continued sublingual immunotherapy but declined routine exposure to shrimp every other day because they had no intention to incorporate crustaceans to their routine diet. On repeat challenge 6-9 months after original challenge, all five patients who had routine exposure to 12-20 g shrimp every other day tolerated the procedure to target dose without any symptoms.

CONCLUSIONS

Desensitization to shrimp by sublingual immunotherapy appears to be safe and effective as shown in this study. Whether the immune modification induced by sublingual immunotherapy is permanent resulting in sustained tolerance, or the achieved degree of desensitization depends on regular exposure is not known; therefore, following challenge, regular consumption three-four times per week was recommended.

High Degree of Desensitization After 1 Year of Early-Life Peanut Oral Immunotherapy: Small Children Oral Immunotherapy (SmaChO) Randomized Controlled Trial

BACKGROUND

The prevalence of peanut allergy is about 2% and mostly lifelong. Studies of oral immunotherapy (OIT) with peanut (the daily oral intake of an initially low and then increasing dose of peanut) often show problematic side effects, but there are indications of better safety and effect in younger children compared with older children and adults.

OBJECTIVE

To determine the safety and effectiveness of peanut OIT with a slow up-dosing strategy and low maintenance dose in children aged 1 to 3 years who were allergic to peanut, through a 1-year interim analysis.

METHOD

In a randomized controlled trial (2:1 ratio), 75 children, median age 31 months (interquartile range [IQR], 23-40 months) were assigned to receive peanut OIT (n = 50) or peanut avoidance (n = 25).

RESULTS

In the OIT and avoidance groups, 43 of 50 and 20 of 25 children, respectively, performed the 1-year open oral peanut challenge. A cumulative dose of 750 mg peanut protein after 1 year was tolerated by 72% (36 of 50 children) in the OIT group compared with 4% (1 of 25) in the avoidance group (P < .001). Median tolerated cumulative dose was 2,750 mg (IQR, 275-5,000 mg) peanut protein in the OIT group compared with 2.8 mg (IQR, 0.3-27.8 mg) in the avoidance group (P < .001). Of the doses administered at home during the first year of OIT, 1.4% resulted in adverse events and 79% were mild, and three doses of epinephrine were given at home to two individuals.

CONCLUSION

In children aged 1 to 3 years, peanut OIT with the combination of slow up-dosing and low maintenance dose seems safe and effective after 1 year.

History of food allergy and where we are today

The food allergy (FA) entity went through a long difficult road which led to much delay in its recognition. After long periods of denial and misdiagnosis, it attained its current designation as food hypersensitivity or allergy. This review will briefly address the evolution of the FA entity from the early BC era until our 21st century and highlight the milestones in the main aspects of diagnosis, treatment, prevention, and research. A great recognition of the allergy specialty was gained by the discovery of its main mediator -immunoglobulin E in 1967 - which also helped in classifying FA into IgE-mediated (immediate-type) and non-IgE-mediated. The cause of the increasing prevalence during the past few decades may be attributed to an increased food consumption and the consequences of modern lifestyle (the hygiene hypothesis). In addition to a skillful medical history-taking, helpful tests have been developed involving the skin or blood. The scratch test was modified to the prick test and in certain instances prick-by-prick. The use of intradermal test has been markedly reduced. Blood testing began by measuring specific-IgE antibodies (sIgE) in the serum using the radioallergosorbent test which went through multiple modifications to avoid radioisotope material and increase the test's sensitivity. The test was advanced to measure sIgE to individual allergen components. Recently, cellular tests were developed in the form of basophil activation or mast cell activation. In most cases, FA needs verification by appropriately-designed challenge testing. Regarding treatment, strict avoidance remains the basic approach. Certain food-labeling regulations led to some improvement in the problem of hidden food allergens but more is desired. Recently some protocols for oral immunotherapy (OIT) showed reasonable safety and efficacy in preventing reactions to accidental exposures. The protocol for peanut has been approved in the United States and other foods are expected to follow. Epicutaneous immunotherapy showed higher safety and promising efficacy. Sublingual immunotherapy might follow as well. Studies on the use of certain biologicals, alone or in combination of OIT, showed promising findings. Very recently, omalizumab was approved in the United States for patients with multiple FA. A major change in the strategy of prevention is the benefit of introducing allergenic foods at an early age (4-6 months). Research on FA markedly flourished in recent decades with increasing numbers of investigators, funding, publications, and education. Despite the major strides, still more awaits exploration with expected better understanding and practice of FA.

Peanut oral immunotherapy using an extensively heated and baked novel composition of peanuts

BACKGROUND

Oral immunotherapy (OIT) is an increasingly acceptable therapeutic option for peanut-allergic (PA) children, despite significant side effects. Major peanut allergenic proteins are heat-resistant and are not rendered hypoallergenic after baking or cooking. Lyophilized peanut protein-MH (LPP-MH) is a novel composition from developing peanuts, enabling cooking-induced reduction in allergenicity. We aimed to explore the safety and efficacy of OIT, with extensively heated and baked (EHEB) LPP-MH in PA children.

METHODS

In a single-arm, single-center, pilot study, PA children with a single highest tolerated dose of <100 mg peanut protein were placed on a 40-week OIT protocol with 300 mg daily of heat-treated LPP-MH. A repeat open peanut food challenge was performed after 40 weeks of treatment and at a 6-12 months of follow-up visit.

RESULTS

Thirty-three children with PA were enrolled, with a mean cumulative tolerated dose (MCTD) of 71.2 mg PP (95% CI 45-100 mg). After 40 weeks, 32/33 patients were able to consume more than 300 mg of natural PP, with MCTD of 1709 mg (CI 365-3675 mg). There were no severe allergic reactions requiring epinephrine, during any of the observed LPP-MH challenges or any treatment related doses at home. After 6-12 months on daily maintenance, the MCTD was 8821 mg (95% CI 1930-13,500 mg). This enabled most children age-appropriate dietary inclusion of peanuts.

CONCLUSION

An OIT protocol with heat-treated LPP-MH, a novel composition from developing peanuts, seems a potentially safe and efficacious OIT modality for PA children, enabling the introduction of dietary levels of peanut proteins in highly allergic PA children. Validation in randomized controlled studies is mandated.

Tolerance-inducing therapies in coeliac disease - mechanisms, progress and future directions

Coeliac disease is an autoinflammatory condition caused by immune reactions to cereal gluten proteins. Currently, the only available treatment for the condition is a lifelong avoidance of gluten proteins in the diet. There is an unmet need for alternative therapies. Coeliac disease has a strong association with certain HLA-DQ allotypes (DQ2.5, DQ2.2 and DQ8), and these disease-associated HLA-DQ molecules present deamidated gluten peptides to gluten-specific CD4+ T cells. The gluten-specific CD4+ T cells are the drivers of the immune reactions leading to coeliac disease. Once established, the clonotypes of gluten-specific CD4+ T cells persist for decades, explaining why patients must adhere to a gluten-free diet for life. Given the key pathogenic role of gluten-specific CD4+ T cells, tolerance-inducing therapies that target these T cells are attractive for treatment of the disorder. Lessons learned from coeliac disease might provide clues for treatment of other HLA-associated diseases for which the disease-driving antigens are unknown. Thus, intensive efforts have been and are currently implemented to bring an effective tolerance-inducing therapy for coeliac disease. This Review discusses mechanisms of the various approaches taken, summarizing the progress made, and highlights future directions in this field.

A murine model of peanut-allergic asthma

Objectives

Peanut allergy is an IgE-mediated food allergy that is associated with asthma in certain patients. With increasing prevalence, its great impact on the quality of life, and a lack of treatment options, the need for new therapy options is a given. Hence, models for research and development are required. This study aimed to establish a murine model of allergic airway inflammation induced by peanut allergens.

Methods

C3H mice were sensitised by intraperitoneal injections of peanut allergen extract and challenged by an intranasal application of the same extract. The assessment of airway inflammation involved the analysis of immune cells in the bronchoalveolar lavage fluid as measured by flow cytometry. Inflammatory reactions in the lung tissue were also studied by histology and quantitative PCR. Moreover, peanut-specific immune responses were studied after re-stimulation of spleen cells in vitro.

Results

Sensitisation led to allergen-specific IgE, IgA, and IgG1 seroconversion. Subsequent nasal exposure led to allergic airway inflammation as manifested by structural changes such as bronchial smooth muscle hypertrophy, mucus cell hyperplasia, infiltration of eosinophil cells and T cells, as well as an upregulation of genes expressing IL-4, IL-5, IL-13, and IFN-γ. Upon re-stimulation of splenocytes with peanut allergen, increased secretion of both T-helper type 2 (Th2) and Th1 cytokines was observed.

Conclusion

We successfully established a peanut-associated asthma model that exhibited many features characteristic of airway inflammation in human patients with allergic asthma. The model holds potential as a tool for investigating novel therapeutic approaches aimed at preventing the development of allergic asthma.

Current state and advances in desensitization for peanut allergy in pediatric age

Peanut allergy affects about 1%-3% of the pediatric population in the world, with an important increase in the last decades. Nowadays, international guidelines recommend the early introduction of peanuts in the infant diet, with poor information about the quantity and the frequency of the intake. Allergen immunotherapy may represent the only therapeutic strategy able to modify the natural history of peanut allergy. In particular, oral immunotherapy showed the most promising results in terms of efficacy, but with significant rates of adverse reactions, mostly gastrointestinal. In 2020, the Food and Drug Administration and the European Medicines Agency approved Palforzia®, an oral drug for patients aged 4-17 years. Several studies are ongoing to improve the tolerability of oral immunotherapy and standardize the desensitization protocols. Sublingual immunotherapy permits to offer much lower doses than oral immunotherapy, but fewer adverse events are shown. Subcutaneous immunotherapy is associated with the greatest systemic adverse effects. Epicutaneous immunotherapy, for which Viaskin® patch was approved, has the highest safety profile. Innovative studies are evaluating the use of biological drugs, such as omalizumab or dupilumab, and probiotics, such as Lactobacillus rhamnosus, in monotherapy or associated with oral immunotherapy. Therapy for peanut allergy is constantly evolving, and new perspectives are ongoing to develop.

Promising New Diagnostic and Treatment Modalities for Allergic Rhinitis: What's Coming Next?

Novel diagnostic tests may help diagnose patients with local allergic rhinitis (AR) when systemic testing is negative or inconclusive. Surgical approaches including septoplasty, inferior turbinate reduction, nasal swell body reduction, and posterior nasal nerve ablation may improve symptoms in patients whose symptoms are refractory to medical therapy, though high-quality evidence is lacking in the AR population. Intralymphatic and epicutaneous immunotherapy have the potential to improve adherence to allergen immunotherapy, though comparisons with current gold standard treatments are lacking and studies reporting long-term outcomes are needed. Immunomodulatory agents in combination with subcutaneous immunotherapy (SCIT) may improve tolerance of SCIT but reports to date do not demonstrate a clear benefit in symptom alleviation. Future work in these areas may support these options as beneficial for testing and treatment of AR.

The Future of Food Allergy Management: Advancements in Therapies

PURPOSE OF REVIEW

To review current and future treatment options for IgE-mediated food allergy.

RECENT FINDINGS

Recent years have seen major developments in both allergen-specific and allergen-non-specific treatment options, with the first FDA-approved peanut oral immunotherapy (OIT) product becoming available in 2020. In addition to OIT, other immunotherapy modalities, biologics, adjunct therapies, and novel therapeutics are under investigation. Food allergy is a potentially life-threatening condition associated with a significant psychosocial impact. Numerous products and protocols are under investigation, with most studies focusing on OIT. A high rate of adverse events, need for frequent office visits, and cost remain challenges with OIT. Further work is needed to unify outcome measures, develop treatment protocols that minimize adverse events, establish demographic and clinical factors that influence candidate selection, and identify patient priorities.

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.

Hot topics in allergen immunotherapy, 2023: Current status and future perspective

The importance of allergen immunotherapy (AIT) is multifaceted, encompassing both clinical and quality-of-life improvements and cost-effectiveness in the long term. Key mechanisms of allergen tolerance induced by AIT include changes in memory type allergen-specific T- and B-cell responses towards a regulatory phenotype with decreased Type 2 responses, suppression of allergen-specific IgE and increased IgG1 and IgG4, decreased mast cell and eosinophil numbers in allergic tissues and increased activation thresholds. The potential of novel patient enrolment strategies for AIT is taking into account recent advances in biomarkers discoveries, molecular allergy diagnostics and mobile health applications contributing to a personalized approach enhancement that can increase AIT efficacy and compliance. Artificial intelligence can help manage and interpret complex and heterogeneous data, including big data from omics and non-omics research, potentially predict disease subtypes, identify biomarkers and monitor patient responses to AIT. Novel AIT preparations, such as synthetic compounds, innovative carrier systems and adjuvants, are also of great promise. Advances in clinical trial models, including adaptive, complex and hybrid designs as well as real-world evidence, allow more flexibility and cost reduction. The analyses of AIT cost-effectiveness show a clear long-term advantage compared to pharmacotherapy. Important research questions, such as defining clinical endpoints, biomarkers of patient selection and efficacy, mechanisms and the modulation of the placebo effect and alternatives to conventional field trials, including allergen exposure chamber studies are still to be elucidated. This review demonstrates that AIT is still in its growth phase and shows immense development prospects.

A Review of Shared Decision-Making, Published Protocols, and Post-desensitization Strategies in Oral Immunotherapy (OIT)

PURPOSE OF REVIEW

The aim of this review is to highlight key published oral immunotherapy (OIT) protocols and post-desensitization strategies for the major food allergens and to cover important concepts to consider when evaluating OIT for food-allergic patients. Shared decision-making should help identify patient and family values which will help influence the type of evidence-based protocol and maintenance strategy to use.

RECENT FINDINGS

With food OIT emerging as a treatment option, there is a pressing need for patients, physicians, and other providers to have a nuanced understanding of the management choices available to them. There are now randomized controlled trials (RCT) of OIT for peanut, egg, milk, and wheat, and reports of cohorts of patients who have undergone OIT for tree nuts and sesame clinically. The current published protocols contain significant diversity in terms of starting dose, build-up schedule, maintenance dose, and even the product used for desensitization. Emerging data can help direct the long-term maintenance strategy for patients on OIT. Based on patient and family values elicited through the shared decision-making process, an OIT protocol may be selected that balances the level of desensitization, potential side effects, frequency of clinic visits, and potential to induce sustained unresponsiveness, among other factors. Once maintenance dosing is reached, most patients will need to maintain regular exposure to the food allergen to remain desensitized. The option to transition to commercial food products with equivalent amounts of food protein as the OIT maintenance dose would simplify the dosing process and perhaps improve palatability as well. Less frequent or decreased OIT dosing can provide practical benefits but may affect the level of desensitization and safety for some patients.

Mobile App/Web Platform for Monitoring Food Oral Immunotherapy in Children: Longitudinal Clinical Validation Study

BACKGROUND

Milk and egg allergies significantly impact the quality of life, particularly in children. In this regard, food oral immunotherapy (OIT) has emerged as an effective treatment option; however, the occurrence of frequent adverse reactions poses a challenge, necessitating close monitoring during treatment.

OBJECTIVE

This study aims to evaluate the ability of a new mobile/web app called OITcontrol to monitor milk and egg OIT.

METHODS

Patients undergoing milk or egg OIT were recruited and divided into 2 groups: the active group used the OITcontrol app in conjunction with standard written monitoring methods, whereas the control group relied solely on written diaries. Investigators documented hospital doses, hospital reactions, and administered treatments on the website. Patients recorded their daily allergen home-dose intake, home reactions, and administered treatments using the app. The following variables were compared between both groups: number and severity of hospital and reported home reactions, patient's adhesion to the OITcontrol app or written diary or both in terms of daily home-dose intake and home reactions recording, and treatment and dose adjustment compliance at home in case of reaction.

RESULTS

Sixteen patients were assigned to be monitored using the OITcontrol app along with additional written methods (active group), while 14 patients relied solely on a written paper diary (control group). A similar distribution was observed in terms of sex, age, basal characteristics, allergen treated in OIT, premedication, and sensitization profile. Active patients reported a comparable number of hospital and home reactions compared with the control group. In terms of recording system usage, 13/16 (81%) active patients used the OITcontrol app, while 10/14 (71%) control patients relied on the written diary. Among active patients, 6/16 (38%) used both methods, and 1 active patient used only written methods. However, control patients recorded home reactions more frequently than active patients (P=.009). Among active patients, the app was the preferred method for recording reactions (59/86, 69%), compared with the written diary (15/86, 17%) or both methods (12/86, 14%; P<.001). Treatment compliance in home-recorded reactions was similar between both groups (P=.15). However, treatment indications after an adverse reaction were more frequently followed (P=.04) in reactions recorded solely in the app (36/59, 61%) than in the written diary (29/71, 41%) or both systems (4/12, 33%). Moreover, compliance with dose adjustments after a moderate-severe reaction in home-recorded reactions was higher in the active group than in the control group (P<.001). Home reactions recorded only in the app (16/19, 84%) were more likely to follow dose adjustments (P<.001) than those recorded in the written diary (3/20, 15%) or using both methods (2/3, 67%).

CONCLUSIONS

The OITcontrol app appears to be a valuable tool for monitoring OIT treatment in children with food allergies. It proves to be a suitable method for recording daily home dose intakes and reactions, and it seems to enhance adherence to treatment indications following an adverse reaction as well as compliance with dose adjustments in home reactions. However, additional studies are necessary to comprehensively grasp the benefits and limitations of using the OITcontrol app in the management of OIT.

Omalizumab for the Treatment of Multiple Food Allergies

BACKGROUND

Food allergies are common and are associated with substantial morbidity; the only approved treatment is oral immunotherapy for peanut allergy.

METHODS

In this trial, we assessed whether omalizumab, a monoclonal anti-IgE antibody, would be effective and safe as monotherapy in patients with multiple food allergies. Persons 1 to 55 years of age who were allergic to peanuts and at least two other trial-specified foods (cashew, milk, egg, walnut, wheat, and hazelnut) were screened. Inclusion required a reaction to a food challenge of 100 mg or less of peanut protein and 300 mg or less of the two other foods. Participants were randomly assigned, in a 2:1 ratio, to receive omalizumab or placebo administered subcutaneously (with the dose based on weight and IgE levels) every 2 to 4 weeks for 16 to 20 weeks, after which the challenges were repeated. The primary end point was ingestion of peanut protein in a single dose of 600 mg or more without dose-limiting symptoms. The three key secondary end points were the consumption of cashew, of milk, and of egg in single doses of at least 1000 mg each without dose-limiting symptoms. The first 60 participants (59 of whom were children or adolescents) who completed this first stage were enrolled in a 24-week open-label extension.

RESULTS

Of the 462 persons who were screened, 180 underwent randomization. The analysis population consisted of the 177 children and adolescents (1 to 17 years of age). A total of 79 of the 118 participants (67%) receiving omalizumab met the primary end-point criteria, as compared with 4 of the 59 participants (7%) receiving placebo (P<0.001). Results for the key secondary end points were consistent with those of the primary end point (cashew, 41% vs. 3%; milk, 66% vs. 10%; egg, 67% vs. 0%; P<0.001 for all comparisons). Safety end points did not differ between the groups, aside from more injection-site reactions in the omalizumab group.

CONCLUSIONS

In persons as young as 1 year of age with multiple food allergies, omalizumab treatment for 16 weeks was superior to placebo in increasing the reaction threshold for peanut and other common food allergens. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT03881696.).

Optimising the management of peanut allergy by targeting immune plasticity

Randomised controlled trials investigating the efficacy of oral tolerance induction to peanut have enabled detailed comparison of their clinical and immunological success. They have demonstrated that the regular consumption of peanut for at least 2 years by babies who are not allergic enables protection from developing peanut allergy. The LEAP study intervention tested the impact of regular peanut consumption for 4 years and demonstrated a sustained protection against the development of peanut allergy even after 12 months of peanut avoidance from 5 to 6 years of age. The PreventADALL trial introduced multiple allergens into babies' diets from early infancy and reduced the prevalence of food allergy at 3 years, especially by protecting against peanut allergy. Immunological studies from the LEAP cohort demonstrated that regular peanut consumption was associated with a prompt induction of peanut-specific IgG4 and reduced manufacture of peanut and Ara h 2-specific IgE. Even after stopping peanut consumption for 5 years, there continued to be a significant fall in peanut-specific Ara h 2 IgE in the consumption group from 5 to 6 years of age (p < .01). Children who developed peanut allergy by 5 years started to develop increasing sensitisation to linear sequential peanut epitopes from 2.5 years of age, suggesting that putative disease-modifying interventions should commence before 3 years. Data comparing clinical outcomes between children undergoing peanut immunotherapy from infancy suggest that younger children can consume higher portions of peanut without reaction on challenge whilst taking immunotherapy, have fewer side effects and are more likely to enjoy remission of PA. Peanut oral immunotherapy modulates T-cell populations in order to bring about hypo-responsiveness of allergy effector cells. Studies are now needed to characterise and compare different states of immunological tolerance. This will accelerate the design of interventions which can promote primary, secondary and tertiary levels of PA prevention across a range of age groups.

Utility of food allergy thresholds

Food allergy is a prevalent disease worldwide that is a significant quality-of-life burden, and accidental exposures to food allergens may elicit severe, life-threatening reactions such as anaphylaxis. The threshold level, or the dose that triggers an allergic reaction determined by oral food challenges, varies considerably among individuals suffering from food allergies. Moreover, IgE concentration, diversity, or function can only partially explain this variation in threshold; pathogenic effector TH2 cells have also been found to contribute to the eliciting dose. Though very sensitive to cofactors such as physical activity/stress, the threshold is a stable and reproducible feature of an individual's allergy over periods of many months, made clear in the past several years from treatment studies in which repeated threshold determination has been used as a treatment outcome; however, there also seem to be age-related changes at a population level. More routine determination of food allergy thresholds may help patients stratify risk to improve the management of their food allergy. Precautionary allergen labeling, such as "may contain" labels, often causes confusion since they are inconsistent and regularly contain little to trace allergen residues; thus, food products with such labeling may be unnecessarily avoided. Population-based eliciting dose levels have been determined in the literature; patients at lower risk with higher thresholds may be more confident with introducing foods with precautionary allergen labels. Understanding a patient's threshold level could aid in shared decision-making to determine the most suitable treatment options for patients, including the starting dose for oral immunotherapy and/or the use of biologics.

New Approaches to Food Allergy Immunotherapy

Food allergy is an increasing public health problem in children and adults. In addition to the risk of potentially severe reactions, food allergy can have a significant burden on quality of life, nutrition, cost of living, and social activities. Traditionally, treatment has primarily included strict food allergen avoidance and use of emergency medications to treat an allergic reaction. However, in recent years, there have been significant strides in the advancement of food allergy treatment, including the approval of the first and only approved therapy (peanut oral immunotherapy) for food allergy in 2020. Clinical trials have primarily focused on food allergen immunotherapy (oral, epicutaneous, sublingual). Building off of a foundation of promising data supporting the efficacy of food oral immunotherapy and our greater understanding of the underlying mechanism of immunotherapy, newer approaches, including alternative routes of delivery, adjuncts to therapy, modified allergens, and utilization in younger patients, aim to provide safer and more effective treatment approaches to the millions of patients burdened by food allergy.

Flex-IT! Applying "Platform Trials" Methodology to Immunotherapy for Food Allergy in Research and Clinical Practice

There is an increasing trend in the management of food allergy toward active treatment using allergen immunotherapy (AIT). Although AIT is efficacious, treatment-related adverse events are common, particularly with oral immunotherapy in those with high levels of allergen-specific IgE sensitization. In clinical practice, these adverse events inevitably create challenges: clinicians and patients routinely face decisions whether to alter the dose itself, the frequency of dosing, and the pace of escalation, or indeed discontinue AIT altogether. Flexibility is therefore needed to adapt treatment, particularly in clinical practice, so that participants are "treated-to-target." For example, this may entail a significant change in the dosing protocol or even switching from one route of administration to another in response to frequent adverse events. We refer to this approach as flexible immunotherapy. However, there is little evidence to inform clinicians as to what changes to treatment are most likely to result in treatment success. Classical clinical trials rely, by necessity, on relatively rigid updosing protocols. To provide an evidence base to optimize AIT, the food allergy community should adopt adaptive platform trials, where a "master protocol" facilitates more efficient evaluation, including longer-term outcomes of multiple interventions. Within a single clinical trial, participants are able to switch between different treatment arms; interventions can be added or dropped without compromising the integrity of the trial. Developing platform trials for food AIT may initially be costly, but they represent a significant opportunity to grow the evidence base (with respect to both treatment outcomes and biomarker discovery) at scale. In addition, they could help understand longitudinal disease trajectories that are difficult to study in clinical trials for food allergy due to the time needed to demonstrate changes in efficacy. Finally, their adoption would achieve greater collaboration and consistency in approaches to proactive management of food allergy in routine clinical practice. As a community, we need to actively pursue this with funders and established research collaborations to deliver the very best outcomes for our patients and their families.

Engineering nanoparticle therapeutics for food allergy

Food allergy is a growing public health issue among children and adults that can lead to life-threatening anaphylaxis following allergen exposure. The criterion standard for disease management includes food avoidance and emergency epinephrine administration because current allergen-specific immunotherapy treatments are limited by adverse events and unsustained desensitization. A promising approach to remedy these shortcomings is the use of nanoparticle-based therapies that disrupt disease-driving immune mechanisms and induce more sustained tolerogenic immune pathways. The pathophysiology of food allergy includes multifaceted interactions between effector immune cells, including lymphocytes, antigen-presenting cells, mast cells, and basophils, mainly characterized by a TH2 cell response. Regulatory T cells, TH1 cell responses, and suppression of other major allergic effector cells have been found to be major drivers of beneficial outcomes in these nanoparticle therapies. Engineered nanoparticle formulations that have shown efficacy at reducing allergic responses and revealed new mechanisms of tolerance include polymeric-, lipid-, and emulsion-based nanotherapeutics. This review highlights the recent engineering design of these nanoparticles, the mechanisms induced by them, and their future potential therapeutic targets.