Oral immunotherapy for treatment of egg allergy in children

Effects of Egg White Consumption on Allergy, Immune Modulation, and Blood Cholesterol Levels in BALB/c Mice

We previously demonstrated that water-soluble egg yolk extract is not related to elevation of serum immunoglobulin E, which can initiate allergic reactions; however, it increases the level of high density lipoprotein (HDL)-cholesterol and the activity of B lymphocytes. In this study, egg white (EW) was fed to BALB/c mice to determine its influence on growth efficiency, immune modulation, and changes in serum lipid levels. A total of 50 five-wk-old BALB/c male mice were divided into 5 groups, 4 of which were fed 0, 10, 50, or 100 mg/d EW for 4 wk. Mice with an uptake of 10, 50 and 100 mg/d EW showed no significant changes in daily weight gain, feed efficiency rate, or populations of white blood cells. However, the activities of both B and T lymphocytes were significantly increased in all three EW groups at the final week of treatment. Interestingly, serum levels immunoglobulin E were not altered by EW consumption, but the IgG level was significantly increased in the 100 mg/d EW group. Serum lipid profile analyses showed no significant changes in total cholesterol, HDL, low density lipoprotein, or triglyceride levels by EW consumption. Taken together, these data demonstrate that consumption of EW promotes immune cell activities and the upregulation of serum IgG levels. However, we found no changes in serum lipid profiles and IgE levels. Therefore, our study suggests that consumption of EW might not be related to the risk of food allergy, but could be an excellent candidate for the maintenance of physiological homeostasis.

Allergist-reported trends in the practice of food allergen oral immunotherapy

Food allergen oral immunotherapy (OIT) is an experimental, immune-modifying therapy that may induce clinical desensitization in some patients. OIT is still in early phase clinical research, but some providers may offer OIT as a clinical service. To understand the current practices of allergists who perform OIT, an online survey was sent by e-mail to members of the American Academy of Allergy Asthma & Immunology. Among 442 respondents, 61 reported participating in using OIT (13.8%), including 28 in nonacademic settings. Informed consent for OIT was obtained by 91.3%, institutional review board approval by 47.7% and Investigational New Drug approval by 38.1%. Compared with nonacademic participants, more academic participants used peanut OIT, obtained institutional review board and Investigational New Drug (P < .0001 respectively), and challenged patients before entry (P = .008). More nonacademic providers billed the patient or insurance for reimbursement (P < .0001). Low reported regard for the importance for US Food and Drug Administration approval or a standardized product (increased odds), and a high regard for better safety data (decreased odds) were associated with considering offering OIT as a service. Significant differences exist with OITs that occur in academic versus nonacademic settings. Further assessment is needed regarding the different motivations and practice styles among providers who offer OIT and those who are considering doing so.

Diagnosis and management of food allergies: new and emerging options: a systematic review

It is reported that 6% of children and 3% of adults have food allergies, with studies suggesting increased prevalence worldwide over the last few decades. Despite this, our diagnostic capabilities and techniques for managing patients with food allergies remain limited. We have conducted a systematic review of literature published within the last 5 years on the diagnosis and management of food allergies. While the gold standard for diagnosis remains the double-blind, placebo-controlled food challenge, this assessment is resource intensive and impractical in most clinical situations. In an effort to reduce the need for the double-blind, placebo-controlled food challenge, several risk-stratifying tests are employed, namely skin prick testing, measurement of serum-specific immunoglobulin E levels, component testing, and open food challenges. Management of food allergies typically involves allergen avoidance and carrying an epinephrine autoinjector. Clinical research trials of oral immunotherapy for some foods, including peanut, milk, egg, and peach, are under way. While oral immunotherapy is promising, its readiness for clinical application is controversial. In this review, we assess the latest studies published on the above diagnostic and management modalities, as well as novel strategies in the diagnosis and management of food allergy.

Peanut immunotherapy

Peanut allergy is common and can be a cause of severe, life-threatening reactions. It is rarely outgrown like other food allergies, such as egg and milk. Peanut allergy has a significant effect on the quality of life of sufferers and their families, due to dietary and social restrictions, but mainly stemming from fear of accidental peanut ingestion. The current management consists of strict avoidance, education and provision of emergency medication, but a disease- modifying therapy is needed for peanut allergy. Recent developments involve the use of immunotherapy, which has shown promise as an active form of treatment. Various routes of administration are being investigated, including subcutaneous, oral, sublingual and epicutaneous routes. Other forms of treatment, such as the use of vaccines and anti-IgE molecules, are also under investigation. So far, results from immunotherapy studies have shown good efficacy in achieving desensitisation to peanut with a good safety profile. However, the issue of long-term tolerance has not been fully addressed yet and larger, phase III studies are required to further investigate safety and efficacy. An assessment of cost/benefit ratio is also required prior to implementing this form of treatment. The use of immunotherapy for peanut allergy is not currently recommended for routine clinical use and should not be attempted outside specialist allergy units.

Sequential transcriptional changes dictate safe and effective antigen-specific immunotherapy

Antigen-specific immunotherapy combats autoimmunity or allergy by reinstating immunological tolerance to target antigens without compromising immune function. Optimization of dosing strategy is critical for effective modulation of pathogenic CD4⁺ T-cell activity. Here we report that dose escalation is imperative for safe, subcutaneous delivery of the high self-antigen doses required for effective tolerance induction and elicits anergic, interleukin (IL)-10-secreting regulatory CD4⁺ T cells. Analysis of the CD4⁺ T-cell transcriptome, at consecutive stages of escalating dose immunotherapy, reveals progressive suppression of transcripts positively regulating inflammatory effector function and repression of cell cycle pathways. We identify transcription factors, c-Maf and NFIL3, and negative co-stimulatory molecules, LAG-3, TIGIT, PD-1 and TIM-3, which characterize this regulatory CD4⁺ T-cell population and whose expression correlates with the immunoregulatory cytokine IL-10. These results provide a rationale for dose escalation in T-cell-directed immunotherapy and reveal novel immunological and transcriptional signatures as surrogate markers of successful immunotherapy.

Dose escalation in antigen-specific therapies is recognized as safe and effective, but the underlying effects of dosing variables on the immune system are not understood. Here, the authors demonstrate that dose escalation causes sequential modulation of gene expression among antigen-specific lymphocytes.

Food allergy: a practice parameter update-2014

This parameter was developed by the Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma & Immunology (JCAAI). The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Food Allergy: A practice parameter update-2014." This is a complete and comprehensive document at the current time. The medical environment is a changing one, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, ACAAI, and JCAAI. These parameters are not designed for use by pharmaceutical companies in drug promotion.

Baseline specific IgE levels are useful to predict safety of oral immunotherapy in egg-allergic children

BACKGROUND

Oral immunotherapy (OIT) is a promising treatment for food allergy but dose-related reactions are common.

OBJECTIVE

To evaluate safety of egg-OIT. To identify predictors of dose-related reactions.

METHODS

Fifty children aged 5-18 underwent egg-OIT after confirming IgE-mediated egg allergy by double-blind placebo-controlled challenge (DBPCFC). All dose-related reactions over a median period of 18 months on-OIT (range: 12-28) were registered. Children were retrospectively divided into three subgroups: (1) children who stopped reacting to OIT-doses over time (RR, Resolved Reactions); (2) children with ongoing dose-related reactions over the whole period on-OIT (PR, Persistent Reactions); (3) children who discontinued OIT within induction phase due to frequent reactions not improved by protocol re-adaptation and medication (ED, Early Discontinuation). Baseline clinical/immunological parameters associated with subgroups were investigated.

RESULTS

Reactions occurred in 7.6% of doses. Adrenaline was required in 26% of children. The three subgroups corresponded to three different safety phenotypes: (1) twenty-four children (48%, RR) experienced infrequent and mainly mild reactions that resolved over time. None required adrenaline; (2) seventeen children (34%, PR) experienced more frequent and severe ongoing reactions over time; (3) nine children (18%, ED) discontinued OIT due to very frequent and mainly moderate reactions. Early discontinuation was associated with underlying asthma, higher specific IgE (sIgE) and lower threshold at DBPCFC. In contrast, lower sIgE and less severe reactions at DBPCFC were associated with subgroup RR. sIgE showed excellent performance in predicting belonging to subgroup RR. Levels below the optimal cut-off (ovomucoid-sIgE 8.85 kU/L) indicated 77% probability of belonging to subgroup RR, whereas levels above it indicated 95% probability of early discontinuation or ongoing reactions over time.

CONCLUSIONS AND CLINICAL RELEVANCE

Egg-OIT involves substantial risks. However, baseline parameters, particularly sIgE, may help identify children in whom the procedure is more likely to be safe. Egg-OIT safety needs improvement in children with more severe and persistent egg allergy.

Successful wheat-specific oral immunotherapy in highly sensitive individuals with a novel multirush/maintenance regimen

We reported a successful oral immunotherapy (OIT) in 2 children with high wheat sensitivity (4 and 14 years old boys). Oral challenges indicated eliciting doses of 300 mg, and wheat flour of 30 mg. The OIT protocol includes 5 days of build-up phase in the hospital, intervening with 2 to 5 months of home maintenance phase. Patients could tolerate 45 g, and 60 g of wheat flour per day, respectively. We have demonstrated that OIT to a large amount of wheat in extremely sensitized patients could be achieved with a stepwise multi oral/maintenance regimen.

Conference Scene: novelties in immunotherapy

The only method aiming to permanently cure allergic disorders is allergen immunotherapy. Over the last 20 years there has been great progress in understanding the mechanisms that govern allergen immunotherapy in order to meet three basic prerequisites: safety, effectiveness and compliance. In the present summary report from the European Academy of Allergology and Clinical Immunology-World Allergy Organization Congress held last June in Milan, we review key points concerning the main axes as diagnosis, novel modalities, routes and protocols, as well as two important immunotherapy fields: food and insect venom allergy.

Oral Immunotherapy for Treatment of Immunoglobulin E-Mediated Food Allergy: The Transition to Clinical Practice

Today, there is neither an effective nor an active treatment for food allergy. Allergy immunotherapy has been proposed as an attractive strategy to actively treat food allergy. Oral immunotherapy (OIT), also known as oral desensitization, is a method of inducing the body's immune system to tolerate a food that causes an allergic overreaction. It has been studied for the use in treatment of immunoglobulin E-mediated food allergy to the most common foods, including milk, egg, and peanut. OIT has been able to desensitize subjects to varying degrees. However, many questions remain unanswered, including efficient formulation, optimal dosing, and induction protocol to achieve full tolerance, transition of OIT to clinical practice, and maximal safety profile. This review focuses on the use of OIT as a new and active treatment for food allergy. The possibility of transition of OIT to clinical practice represents, in this field, the next pivotal step with the goal of improving the quality of life of patients with food allergy and their families.

Low-allergenic hydrolyzed egg induces oral tolerance in mice

BACKGROUND

Egg allergy is one of the most common food allergies in children. The standard therapy for egg allergy is strict avoidance. Yet, there is considerable clinical and scientific interest in primary or secondary prevention. A major drawback of oral tolerance (OT) induction protocols, however, is the possibility of severe side effects; thus, we have formulated a hypoallergenic egg product and demonstrate its in vivo capacity to modulate the immune system in the current study.

METHODS

Hydrolyzed egg (HE) was produced using a combination of moderate heat treatment and enzymatic hydrolysis. The capacity of HE to induce OT was tested in experimental models and compared to whole egg (WE). Delayed-type hypersensitivity (DTH) responses, immune markers and potential early markers of OT were analyzed.

RESULTS

Allergic responses, assessed by both DTH responses upon OVA challenge and serum OVA-specific IgE and IgG1, were decreased after treatment with HE and WE compared to the control group. Additionally, feeding WE and HE significantly decreased Th2 cytokine induction and cell proliferation, induced the activation of effector CD4+ T cells and increased numbers and percentages of ICOS+CD4+CD25+Foxp3+ cells. Furthermore, DO11.10 mouse experiments showed that HE contains other peptides than the OVA323-339 peptide that are able to induce tolerance to OVA.

CONCLUSIONS

Altogether, results showed that HE induces OT in mice in a dose-dependent manner. Due to its low allergenicity compared to WE, it may represent a safer alternative for OT induction in at-risk subjects or oral immunotherapy in allergic patients.

State of the art on food allergen immunotherapy: oral, sublingual, and epicutaneous

IgE-mediated food allergy is a global health problem that affects millions of persons and affects every aspect of life for the patient. Developing effective treatment strategies to augment current practice standards of strict dietary avoidance of antigens and availability of self-injectable epinephrine has been a major focus of research teams, advocacy groups, funding agencies, and patients and their families. Significant progress has been made through the development of allergen-specific immunotherapy encompassing 3 major forms of treatment: oral, sublingual, and epicutaneous immunotherapy. These therapies are in various stages of clinical investigation, with some successes noted in clinical outcomes and modulation of immune mechanisms toward effective therapy. Here we review recent progress and areas of concern for the role of these forms of immunotherapy as an emerging treatment for food allergy.

Multiple-allergen oral immunotherapy improves quality of life in caregivers of food-allergic pediatric subjects

BACKGROUND

Food allergy (FA) negatively affects quality of life in caregivers of food-allergic children, imposing a psychosocial and economic burden. Oral immunotherapy (OIT) is a promising investigational therapy for FA. However, OIT can be a source of anxiety as it carries risk for allergic reactions. The effect of OIT with multiple food allergens (mOIT) on FA-specific health-related quality of life (HRQL) has never been studied in participants with multiple, severe food allergies. This study is the first to investigate the effects of mOIT on FA-related HRQL in caregivers of pediatric subjects.

METHODS

Caregiver HRQL was assessed using a validated Food Allergy Quality of Life - Parental Burden (FAQL-PB) Questionnaire (J Allergy Clin Immunol 114(5):1159-1163, 2004). Parents of participants in two single-center Phase I clinical trials receiving mOIT (n = 29) or rush mOIT with anti-IgE (omalizumab) pre-treatment (n = 11) completed the FAQL-PB prior to study intervention and at 2 follow-up time-points (6 months and 18 months). Parents of subjects not receiving OIT (control group, n = 10) completed the FAQL-PB for the same time-points.

RESULTS

HRQL improved with clinical (change < -0.5) and statistical (p < 0.05) significance in the mOIT group (baseline mean 3.9, 95% CI 3.4-4.4; 6-month follow-up mean 2.5, 95% CI 2.0-3.0; 18-month follow-up mean 1.8, 95% CI 1.4-2.1) and rush mOIT group (baseline mean 3.9, 95% CI 3.1-4.7; 6-month follow-up mean 1.7, 95% CI 0.9-2.6; 18-month follow-up mean 1.3, 95% CI 0.3-2.4). HRQL scores did not significantly change in the control group (n = 10).

CONCLUSION

Multi-allergen OIT with or without omalizumab leads to improvement in caregiver HRQL, suggesting that mOIT can help relieve the psychosocial and economic burden FA imposes on caregivers of food-allergic children.

Immunotherapy: what lies beyond

Allergen immunotherapy has been used to treat allergic diseases, such as asthma, allergic rhinitis, and venom allergy, since first described over a century ago. The current standard of care in the United States involves subcutaneous administration of clinically relevant allergens for several months, building up to eventual monthly injections for typically 3 to 5 years. Recent advances have improved the safety and efficacy of immunotherapy. The addition of omalizumab or Toll-like receptor agonists to standard subcutaneous immunotherapy has proved beneficial. Altering the extract itself, either through chemical manipulation producing allergoids or directly producing recombinant proteins or significant peptides, has been evaluated with promising results. The use of different administration techniques, such as sublingual immunotherapy, is common in Europe and is on the immediate horizon in the United States. Other methods of administering allergen immunotherapy have been studied, including epicutaneous, intralymphatic, intranasal, and oral immunotherapy. In this review we focus on new types and routes of immunotherapy, exploring recent human clinical trial data. The promise of better immunotherapies appears closer than ever before, but much work is still needed to develop novel immunotherapies that induce immunologic tolerance and enhanced clinical efficacy and safety over that noted for subcutaneous allergen immunotherapy.

Immunotherapy in allergy and cellular tests: state of art

The basophil activation test (BAT) is an in vitro assay where the activation of basophils upon exposure to various IgE-challenging molecules is measured by flow cytometry. It is a cellular test able to investigate basophil behavior during allergy and allergy immunotherapy. A panoply of critical issues and suggestive advances have rendered this assay a promising yet puzzling tool to endeavor a full comprehension of innate immunity of allergy desensitization and manage allergen or monoclonal anti-IgE therapy. In this review a brief state of art of BAT in immunotherapy is described focusing onto the analytical issue pertaining BAT performance in allergy specific therapy.

Emerging therapies for food allergy

Food allergy is a common condition for which there are currently no approved treatments except avoidance of the allergenic food and treatment of accidental reactions. There are several potential treatments that are under active investigation in animal and human studies, but it is not yet clear what the best approach may be. Here, we review approaches that are currently in clinical trials, including oral, sublingual, and epicutaneous immunotherapy, immunotherapy combined with anti-IgE, and Chinese herbal medicine as well as approaches that are in preclinical or early clinical investigation, including modified protein immunotherapy, adjuvants, DNA vaccines, and helminth administration. We discuss the importance of fully exploring the risks and benefits of any treatment before it is taken to general clinical practice and the need for clarity about the goals of treatment.

Food allergy in children: what is new?

PURPOSE OF REVIEW

Food allergy affects up to 10% of preschool children, and continues to increase in prevalence in many countries, resulting in a major public health issue, with practical implications for the food industry, educational establishments and healthcare systems.

RECENT FINDINGS

The need to distinguish between food allergen sensitization and true clinical reactivity remains crucial in diagnosis, often requiring formal food challenge to avoid unnecessary dietary elimination. Epicutaneous exposure in the absence of oral tolerance induction during infancy may be an important risk factor for food allergy. Mounting evidence suggests that for milk and egg allergens, many children are able to tolerate the food when heat-modified, and that this may hasten resolution of the allergy.

SUMMARY

These developments will hopefully result in a lower adverse impact on quality of life for food-allergic individuals and their families.

Clinical studies in oral allergen-specific immunotherapy: differences among allergens

Oral immunotherapy (OIT) is a significant focus of treatment of food allergy. OIT appears to be effective in inducing desensitization, however, patients receiving OIT frequently developmild/moderate symptoms during the therapy. It has not been clearly established whether the clinical tolerance induced by OIT resembles natural tolerance. According to our data, the efficacy of OIT is different among food antigens, and it is comparatively difficult to achieve the clinical tolerance in milk OIT. Moreover, the definitive evidence of efficacy and safety with long-term therapy is limited. Further studies need to be offered to patients in clinical practice. Recently, novel treatments for food allergy, sublingual and epicutaneous immunotherapy, and combination treatment with an anti-IgE monoclonal antibody (omalizumab), have been examined in some studies. OIT combined with omalizumab increased the threshold doses of food without adverse reactions and may be of benefit in food allergy treatment. More studies are needed to demonstrate long-term safety and treatment benefits in a larger patient cohort.

Immunotherapy: a new horizon for egg allergy?

Egg allergy is the second most frequent food allergy in children of the Western Countries, with an overall prevalence of 1-3%. Today strict avoidance diet is the only treatment, but its feasibility is difficult to obtain in childhood because of the large amount of egg proteins present in different foods. From 1998, a growing number of protocols on immunotherapy for egg allergy have been published, but all of them differ for patients' age, inclusion of high-risk patients, amount of allergen administered, duration of the protocols and presence of a control group. We reviewed the protocols performed in the last 15 years, to underline the most important issues in this kind of food immunotherapy, and the rates of tolerance or desensitization induction.

The role of B regulatory cells and Semaphorin3A in atopic diseases

When the pathogenesis of allergic inflammatory diseases such as asthma, allergic rhinitis and atopic dermatitis is discussed, one should take into consideration the involvement of regulatory cells/molecules whose role is to prevent the induction and/or deterioration of such diseases. The involvement of T regulatory cells and FoxPp3 is well established in asthma, but only little is known about the involvement of B regulatory cells (Bregs) and the soluble regulatory molecule semaphorin3A (sema3A) in atopic diseases. During the last decade, research has sought to better define the various subtypes of Breg cells and how similar they are to their parallel subtypes of Tregs. In this review, we focus on the newly reported role of Bregs in both experimental and human models of asthma. Bregs are also involved in the pathophysiology of food allergy. We also show how sema3A plays a role in the pathogenesis of allergic rhinitis and atopic dermatitis. Determining the above processes could facilitate the use of regulatory molecules as therapeutic tools in treating these diseases.

Future Therapies for IgE-Mediated Food Allergy

Food allergy is prevalent, affecting approximately 4-8% of children. There is no currently approved treatment for food allergy, and while strict allergen avoidance is recommended it is difficult to achieve and therefore accidental exposures and reactions are common. There is an urgent need for the development of therapeutic approaches that will improve the health and quality of life of children with food allergy. The majority of current clinical research focus is on specific food allergen immunotherapy through oral, sublingual, or epicutaneous routes. Pre-clinical research has focused on making improvements to the safety and efficacy of allergen immunotherapy through modifications of allergen structure and addition of immuno-modulatory factors. The number of novel therapeutics for food allergy reaching the level of clinical trials remains disappointingly low, and there is a need for an expansion of pre-clinical research to provide safe, practical and novel approaches to the treatment of food allergy.

Oral and sublingual immunotherapy

Allergic diseases have continued to increase throughout the developed world. Subcutaneous immunotherapy has been a mainstay of treatment for allergic rhinitis and asthma, however, some patients are precluded from treatment. On the other hand, in the case of food allergy, treatments simply do not exist. Oral and sublingual immunotherapy, with its superior safety and ease of administration, offers an alternative for patients with allergic rhinitis and asthma and has also been promising as a potential treatment for food allergy. The review summarizes significant advances from the past year including further data on the effectiveness of existing treatments, preliminary data on novel treatments, and further understanding of the mechanisms of these new therapies.

Home-based oral immunotherapy (OIT) with an intermittent loading protocol in children unlikely to outgrow egg allergy

Background

Home based oral immunotherapy (OIT) for food allergy has often been used for young children in Japan, the majority of whom are believed to outgrow the allergy by the school age, therefore the true efficacy of the therapy has been controversial. The aim of this study was to evaluate the efficacy and safety of a newly developed slow- type home-based oral immunotherapy (OIT) regimen in children with hen’s egg (HE) allergy, who had low likelihood of outgrowing the allergy, with treatment involving only elimination diet.

Method

We retrospectively reviewed the medical records of 43 children with egg allergy (30 males; median age 6) who fulfilled Burks et al.’s criteria of being unlikely to outgrow the allergy. Thirty children who agreed to start OIT were assigned to the treatment group, and 13 who did not want to participate immediately were assigned to the untreated group; the patients underwent an elimination diet for 1 year, during which they were monitored. The OIT regimen involved the intake of the maximum tolerated dose 2 to 3 times a week at home, with initial dose introduction followed by dose build-ups with medical supervision. We statistically evaluated the rate of children who changed their threshold up to 32 g of egg – defined as, oral tolerance induction– in both the groups for 1 year and in the OIT group for 2 years, as well as the rate of children who fulfilled Savage et al.’s criteria of clinical tolerance after reaching the abovementioned remission stage.

Results

The rate of children who achieved oral tolerance induction to 32 g of egg after 1 year in the OIT group (9/30) was significantly higher than that in the untreated group (0/13). The total rate within the OIT group was significantly increased from 9/30 at 1 year to 17/30 at two years without any severe adverse reaction; of the above 17 children, we followed 14 children, and noted that 11 of these were able to obtain clinical tolerance.

Conclusion

The home-based OIT with an intermittent loading protocol was very safe and effective in children with a low likelihood of outgrowing egg allergy.

Phase 1 results of safety and tolerability in a rush oral immunotherapy protocol to multiple foods using Omalizumab

BACKGROUND

Up to 30% of patients with food allergies have clinical reactivity to more than one food allergen. Although there is currently no cure, oral immunotherapy (OIT) is under investigation. Pilot data have shown that omalizumab may hasten the ability to tolerate over 4 g of food allergen protein.

OBJECTIVE

To evaluate the safety and dose tolerability of a Phase 1 Single Site OIT protocol using omalizumab to allow for a faster and safe desensitization to multiple foods simultaneously.

METHODS

Participants with multiple food allergies received OIT for up to 5 allergens simultaneously with omalizumab (rush mOIT). Omalizumab was administered for 8 weeks prior to and 8 weeks following the initiation of a rush mOIT schedule. Home reactions were recorded with diaries.

RESULTS

Twenty-five (25) participants were enrolled in the protocol (median age 7 years). For each included food, participants had failed an initial double-blind placebo-controlled food challenge at a protein dose of 100 mg or less. After pre-treatment with omalizumab, 19 participants tolerated all 6 steps of the initial escalation day (up to 1250 mg of combined food proteins), requiring minimal or no rescue therapy. The remaining 6 were started on their highest tolerated dose as their initial daily home doses. Participants reported 401 reactions per 7,530 home doses (5.3%) with a median of 3.2 reactions per 100 doses. Ninety-four percent (94%) of reactions were mild. There was one severe reaction. Participants reached their maintenance dose of 4,000 mg protein per allergen at a median of 18 weeks.

CONCLUSION

These phase 1 data demonstrate that rush OIT to multiple foods with 16 weeks of treatment with omalizumab could allow for a fast desensitization in subjects with multiple food allergies. Phase 2 randomized controlled trials are needed to better define safety and efficacy parameters of multi OIT experimental treatments with and without omalizumab.

Sustained unresponsiveness to peanut in subjects who have completed peanut oral immunotherapy

BACKGROUND

Although peanut oral immunotherapy (OIT) has been conclusively shown to cause desensitization, it is currently unknown whether clinical protection persists after stopping therapy.

OBJECTIVE

Our primary objective was to determine whether peanut OIT can induce sustained unresponsiveness after withdrawal of OIT.

METHODS

We conducted a pilot clinical trial of peanut OIT at 2 US centers. Subjects age 1 to 16 years were recruited and treated for up to 5 years with peanut OIT. The protocol was modified over time to permit dose increases to a maximum of 4000 mg/d peanut protein. Blood was collected at multiple time points. Clinical end points were measured with 5000-mg double-blinded, placebo-controlled food challenges once specific criteria were met.

RESULTS

Of the 39 subjects originally enrolled, 24 completed the protocol and had evaluable outcomes. Twelve (50%) of 24 successfully passed a challenge 1 month after stopping OIT and achieved sustained unresponsiveness. Peanut was added to the diet. At baseline and the time of challenge, such subjects had smaller skin test results, as well as lower IgE levels specific for peanut, Ara h 1, and Ara h 2 and lower ratios of peanut-specific IgE/total IgE compared with subjects not passing. There were no differences in peanut IgG₄ levels or functional activity at the end of the study.

CONCLUSIONS

This is the first demonstration of sustained unresponsiveness after peanut OIT, occurring in half of subjects treated for up to 5 years. OIT favorably modified the peanut-specific immune response in all subjects completing the protocol. Smaller skin test results and lower allergen-specific IgE levels were predictive of successful outcome.

Acute and long-term management of food allergy: systematic review

BACKGROUND

Allergic reactions to food can have serious consequences. This systematic review summarizes evidence about the immediate management of reactions and longer-term approaches to minimize adverse impacts.

METHODS

Seven bibliographic databases were searched from their inception to September 30, 2012, for systematic reviews, randomized controlled trials, quasi-randomized controlled trials, controlled clinical trials, controlled before-and-after and interrupted time series studies. Experts were consulted for additional studies. There was no language or geographic restrictions. Two reviewers critically appraised the studies using the appropriate tools. Data were not suitable for meta-analysis due to heterogeneity so were narratively synthesized.

RESULTS

Eighty-four studies were included, but two-thirds were at high risk of potential bias. There was little evidence about acute management for non-life-threatening reactions. H1-antihistamines may be of benefit, but this evidence was in part derived from studies on those with cross-reactive birch pollen allergy. Regarding long-term management, avoiding the allergenic food or substituting an alternative was commonly recommended, but apart from for infants with cow's milk allergy, there was little high-quality research on this management approach. To reduce symptoms in children with cow's milk allergy, there was evidence to recommend alternatives such as extensively hydrolyzed formula. Supplements such as probiotics have not proved helpful, but allergen-specific immunotherapy may be disease modifying and therefore warrants further exploration.

CONCLUSIONS

Food allergy can be debilitating and affects a significant number of people. However, the evidence base about acute and longer-term management is weak and needs to be strengthened as a matter of priority.

The natural history of egg allergy in an observational cohort

BACKGROUND

There are few studies on the natural history of egg allergy, and most are single-site and nonlongitudinal and have not identified early predictors of outcomes.

OBJECTIVE

We sought to describe the natural course of egg allergy and to identify early prognostic markers.

METHODS

Children age 3 to 15 months were enrolled in a multicenter observational study with either (1) a convincing history of an immediate allergic reaction to egg, milk, or both with a positive skin prick test (SPT) response to the trigger food and/or (2) moderate-to-severe atopic dermatitis and a positive SPT response to egg or milk. Children enrolled with a clinical history of egg allergy were followed longitudinally, and resolution was established based on successful ingestion.

RESULTS

The cohort with egg allergy consists of 213 children followed to a median age of 74 months. Egg allergy resolved in 105 (49.3%) children at a median age of 72 months. Factors that were most predictive of resolution included the following: initial reaction characteristics (isolated urticaria/angioedema vs other presentations), baseline egg-specific IgE level, egg SPT wheal size, atopic dermatitis severity, IgG4 level, and IL-4 response (all P < .05). Numerous additional baseline clinical and demographic factors and laboratory assessments were not associated with resolution. Multivariate analysis identified baseline egg-specific IgE levels and initial reaction characteristics as strongly associated with resolution; a calculator to estimate resolution probabilities using these variables was established.

CONCLUSIONS

In this cohort of infants with egg allergy, approximately one half had resolved over 74 months of follow-up. Baseline egg-specific IgE levels and initial reaction characteristics were important predictors of the likelihood of resolution.

Peanut oral immunotherapy results in increased antigen-induced regulatory T-cell function and hypomethylation of forkhead box protein 3 (FOXP3)

BACKGROUND

The mechanisms contributing to clinical immune tolerance remain incompletely understood. This study provides evidence for specific immune mechanisms that are associated with a model of operationally defined clinical tolerance.

OBJECTIVE

Our overall objective was to study laboratory changes associated with clinical immune tolerance in antigen-induced T cells, basophils, and antibodies in subjects undergoing oral immunotherapy (OIT) for peanut allergy.

METHODS

In a phase 1 single-site study, we studied participants (n = 23) undergoing peanut OIT and compared them with age-matched allergic control subjects (n = 20) undergoing standard of care (abstaining from peanut) for 24 months. Participants were operationally defined as clinically immune tolerant (IT) if they had no detectable allergic reactions to a peanut oral food challenge after 3 months of therapy withdrawal (IT, n = 7), whereas those who had an allergic reaction were categorized as nontolerant (NT; n = 13).

RESULTS

Antibody and basophil activation measurements did not statistically differentiate between NT versus IT participants. However, T-cell function and demethylation of forkhead box protein 3 (FOXP3) CpG sites in antigen-induced regulatory T cells were significantly different between IT versus NT participants. When IT participants were withdrawn from peanut therapy for an additional 3 months (total of 6 months), only 3 participants remained classified as IT participants, and 4 participants regained sensitivity along with increased methylation of FOXP3 CpG sites in antigen-induced regulatory T cells.

CONCLUSION

In summary, modifications at the DNA level of antigen-induced T-cell subsets might be predictive of a state of operationally defined clinical immune tolerance during peanut OIT.

Metabolic syndrome - Removing roadblocks to therapy: Antigenic immunotherapies

Up to 25 per cent of the world׳s adult population may have the metabolic syndrome, a condition closely associated with central obesity. The metabolic syndrome is a major risk factor for cardiovascular disease and type 2 diabetes and therefore represents an important worldwide health problem. In addition to metabolic abnormalities such as raised fasting plasma glucose, high cholesterol and high blood pressure, there is consensus that obese subjects develop a state of low-grade chronic immune activation. This sustained pro-inflammatory response in fat tissue is thought to worsen insulin resistance and dyslipidemia. Likewise, the immune system contributes to the detrimental cascade of events leading to plaque formation in atherosclerosis. It has long been assumed that the innate arm of the immune system was the only key player, but emerging evidence suggests that there is in fact a sizeable adaptive immune component to obesity and cardiovascular disease. From a therapeutic perspective, it could be envisioned that immune modulation drugs such as cytokine inhibitors, co-stimulation blockers or anti-T cell agents could offer benefit. It is questionable, however, whether chronic treatment with for instance biologicals will have a favorable risk/benefit profile in a silent condition such as the metabolic syndrome. An attractive alternative could be the development of antigen-specific T cell therapies, not unlike those currently in various phases of development for type 1 diabetes. In this article, we will give an overview of antigen-specific treatment modalities in type 1 diabetes, followed by a review of the evidence for T cell involvement in obesity and atherosclerosis.

Safety and feasibility of oral immunotherapy to multiple allergens for food allergy

Background

Thirty percent of children with food allergy are allergic to more than one food. Previous studies on oral immunotherapy (OIT) for food allergy have focused on the administration of a single allergen at the time. This study aimed at evaluating the safety of a modified OIT protocol using multiple foods at one time.

Methods

Participants underwent double-blind placebo-controlled food challenges (DBPCFC) up to a cumulative dose of 182 mg of food protein to peanut followed by other nuts, sesame, dairy or egg. Those meeting inclusion criteria for peanut only were started on single-allergen OIT while those with additional allergies had up to 5 foods included in their OIT mix. Reactions during dose escalations and home dosing were recorded in a symptom diary.

Results

Forty participants met inclusion criteria on peanut DBPCFC. Of these, 15 were mono-allergic to peanut and 25 had additional food allergies. Rates of reaction per dose did not differ significantly between the two groups (median of 3.3% and 3.7% in multi and single OIT group, respectively; p = .31). In both groups, most reactions were mild but two severe reactions requiring epinephrine occurred in each group. Dose escalations progressed similarly in both groups although, per protocol design, those on multiple food took longer to reach equivalent doses per food (median +4 mo.; p < .0001).

Conclusions

Preliminary data show oral immunotherapy using multiple food allergens simultaneously to be feasible and relatively safe when performed in a hospital setting with trained personnel. Additional, larger, randomized studies are required to continue to test safety and efficacy of multi-OIT.

Trial registration

Clinicaltrial.gov NCT01490177

Egg allergy: an update

Egg allergy is the commonest infant food allergy both in Australia and world-wide. The clinical presentation of egg allergy is varied - egg is involved in both IgE and non-IgE-mediated allergic reactions and has been implicated in conditions such as anaphylaxis, food protein-induced enterocolitis syndrome, atopic dermatitis and eosinophilic oesophagitis. The clinical presentation, pathophysiology and diagnosis as well as the natural history and management of egg allergy will be discussed. Current theories about primary prevention as well as potential future therapies are presented. Finally, practical information about egg allergy and immunisation is provided.

Duration of a cow-milk exclusion diet worsens parents' perception of quality of life in children with food allergies

BACKGROUND

In Italy, rigorous studies obtained with specific and validated questionnaires that explore the impact of exclusion diets on health-related quality of life (HRQoL) in children with food allergies are lacking. In this cross-sectional study, we wished to validate the Italian version of a disease-specific quality of life questionnaire, and assess the impact of exclusion diets on the HRQoL in a cohort of Italian children with IgE-mediated food allergies.

METHODS

Children on an exclusion diet for ≥1 food were enrolled consecutively, and their parents completed the validated Italian version of the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) and Food Allergy Independent Measure (FAIM).

RESULTS

Ninety-six parents of children aged 0-12 years answered the FAQLQ-PF. The validity of the construct of the questionnaire was assessed by correlation between the FAQLQ-PF and FAIM-PF (r = 0.85). The Italian version of the FAQLQ had good internal consistency (Cronbach's α >0.70). Factors that mainly influenced the HRQoL were older age, severity of food allergy, and the duration of the cow milk-exclusion diet.

CONCLUSIONS

The FAQLQ-PF, validated in Italian, is a reliable instrument. Worse QoL scores were observed among older children, those with severe systemic reactions, and those with a prolonged cow milk-free diet. It is very important to consider the QoL assessment as an integral part of food-allergy management. These results emphasize the need to administer exclusion diets only for the necessary time and the importance of assessment of the HRQoL in these patients.

Trials in type 1 diabetes: Antigen-specific therapies

Type 1 diabetes (T1D) results from an aberrant immunological response against the insulin-producing beta cells in the islets of the pancreas. The ideal therapy would restore immune balance in a safe and lasting fashion, stopping the process of beta cell decay. The efficacy of immune suppressive agents such as cyclosporin underscores the notion that T1D can in principle be prevented, albeit at an unacceptable long-term safety risk. Immune modulatory drugs such as monoclonal anti-CD3 antibody, on the other hand, have recently had rather disappointing results in phase 3 trials, possibly due to inadequate dosing or choice of inappropriate endpoints. Therefore, it is argued that striking the right balance between safety and efficacy, together with careful trial design, will be paramount in preventing T1D. Here we outline the concept of antigen-specific tolerization as a strategy to safely induce long-term protection against T1D, focusing on available clinical trial data, key knowledge gaps and potential future directions.

Food Allergy

Food allergy has established itself as a matter of significant public health importance and relevance. It has had substantial impacts across the world and continues to represent the most common cause of anaphylaxis seen in emergent settings. However, its increasing incidence has yielded a silver lining of increased interest and investment, which has powered major research in the field. Much has been learned about food allergy as a result. Recent work has elicited increased understanding about food allergy prevalence, mechanisms, and risk factors. In turn, this has allowed for application of this understanding to potential treatments. Current practice of food allergy treatment through restricted exposure may ultimately be replaced with novel therapies including, perhaps ironically, introduction of the allergenic foods in question. This review presents broad highlights of the rapidly increasing understanding into food allergy mechanisms and experimental therapies.

IgE-mediated food allergy in children

Food allergy is a serious health issue affecting roughly 4% of children, with a substantial effect on quality of life. Prognosis is good for the most frequent allergens with almost all children outgrowing their allergy. However, the long-term implications for disease burden are substantial for children with persistent allergies (eg, peanuts, tree nuts, fish, and shellfish) and for those with high concentrations of milk, egg, and wheat IgE. Antigen avoidance has been the time-honoured approach both for prevention and treatment. However, findings from studies done in the past 5 years show that early contact with food can induce tolerance and desensitisation to foods. We review the epidemiology, natural history, and management of food allergy, and discuss the areas of controversy and future directions in research and clinical practice.

Non-antigenic and antigenic interventions in type 1 diabetes

Type 1 diabetes (T1D) results from autoimmune destruction of the pancreatic β-cells. Current T1D therapies are exclusively focused on regulating glycemia rather than the underlying immune response. A handful of trials have sought to alter the clinical course of T1D using various broad immune-suppressors, e.g., cyclosporine A and azathioprine.^1–3 The effect on β-cell preservation was significant, however, these therapies were associated with unacceptable side-effects. In contrast, more recent immunomodulators, such as anti-CD3 and antigenic therapies such as DiaPep277, provide a more targeted immunomodulation and have been generally well-tolerated and safe; however, as a monotherapy there appear to be limitations in terms of therapeutic benefit. Therefore, we argue that this new generation of immune-modifying agents will likely work best as part of a combination therapy. This review will summarize current immune-modulating therapies under investigation and discuss how to move the field of immunotherapy in T1D forward.