Oral rush desensitization to egg: efficacy and safety

Variations in protocol development during oral immunotherapy

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

Oral Immunotherapy (OIT): A Personalized Medicine

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

Egg OIT in clinical practice (SEICAP II): Maintenance patterns and desensitization state after normalizing the diet

BACKGROUND

It is unknown which are the most suitable maintenance pattern and egg consumption to maintain the desensitization state after ending the oral immunotherapy (OIT). This multicenter, randomized, controlled trial compared two OIT maintenance patterns with pasteurized egg white (PEW), evaluating the egg consumption effect on the desensitization state after ending the OIT.

METHODS

One hundred and one children with confirmed egg allergy were randomized: 25 to an egg-free diet (CG) and 76 to an OIT year with PEW and two maintenance patterns, 38 patients to daily 3.3 g proteins (AG) and 38 to every two days (BG). PEW challenge (DBPCFC), adverse reactions, and immune markers were assessed at baseline, at the end of the OIT, and at 6 and 12 months later on ad libitum egg consumption (T0, T12, T18, and T24). A questionnaire evaluated the egg consumption at T18.

RESULTS

At T12, 64 of 76 (84.21%) OIT patients had reached total desensitization (32 AG and 32 BG) vs 4 of 25 (16.00%) CG who passed the PEW DBPCFC. Thirty (93.75%) AG vs 25 (78.12%) BG patients completed an OIT year. At T18, 27 of 29 (93.1%) AG vs 20 of 24 (83.3%) BG passed the PEW DBPCFC, 96% consuming at least two egg servings/week. At T24, 97.43% OIT patients passed the challenge. Most patients had adverse reactions, more frequent in the BG patients; frequency and severity of reactions decreased through the study. PEW skin prick test wheal and sIgE antibody serum levels similarly decreased in AG or BG, but AG patients had greater increase in PEW sIgG4 (P < 0.05).

CONCLUSIONS

Daily OIT maintenance achieves better adherence, effectiveness, and safety. Two egg servings/week ensure maintained desensitization after the end of an OIT year.

Egg oral immunotherapy in children (SEICAP I): Daily or weekly desensitization pattern

BACKGROUND

Studies are required before incorporating egg oral immunotherapy (OIT) into clinical practice. The Spanish Society of Pediatric Allergy, Asthma and Clinical Immunology (SEICAP) conducted a multicenter, randomized controlled study assessing the effectiveness and safety of the OIT using pasteurized egg white (PEW) in egg-allergic children.

METHODS

One hundred and one egg-allergic children (6-9 years) were randomized for 1 year: 25 to an egg-free-diet (CG) and 76 to OIT (target dose 3.3 g PEW proteins), PI (30% weekly plus 5% daily increments) or PII (only 30% weekly increments) buildup patterns. Egg skin prick test, sIgE and sIgG4 serum levels, PEW double-blind placebo-controlled food challenge (DBPCFC), and dosing adverse reactions (DARs) were evaluated in all patients from inclusion (T0) until completing 1 year of follow-up (T12). At T12, egg-allergic control patients could start OIT. The effectiveness and safety of OIT and the effect of the buildup pattern were analyzed.

RESULTS

At T12, 4/25 (16.0%) CG patients passed the PEW DBPCFC vs 64/76 (84.2%) OIT that reached total desensitization (P = 0.000); 12 egg-allergic control patients started OIT. Finally, 72/88 (81.81%) patients reached total desensitization, 96.15% PI vs 75.80% on PII (P = 0.01). Induction period (121.12 ± 91.43, median 98.00 days) was longer in patients on PII buildup pattern, and those with allergic asthma, minor threshold dose, or higher egg sIgE (P < 0.05). Most patients (89.06%) developed DARs: 74.53% were mild; 21.90% moderate; and 3.5% requiring adrenaline-treatment. Moderate reactions and those requiring adrenaline were more frequent in patients with allergic asthma, PII pattern, or higher egg sIgE serum antibody levels (P < 0.05).

CONCLUSIONS

PEW OIT is an effective treatment for children with persistent egg allergy. A 30% weekly plus 5% daily increment pattern could be more effective and safer than one with only 30% weekly increments.

Oral and Sublingual Immunotherapy for Treatment of IgE-Mediated Food Allergy

Development of active therapies for IgE-mediated food allergy is a critical action step toward alleviating the adverse medical, psychosocial, and economic burdens on affected patients and families. Significant progress has been observed specifically in the application of single-allergen oral and sublingual immunotherapy for treatment of IgE-mediated food allergy, with emphasis on milk, egg, and peanut as the primary allergens. Oral immunotherapy (OIT) has demonstrated efficacy in promoting immunomodulatory effects that lead to the clinical outcome of desensitization, defined as reduced reactivity while on active OIT, in the majority of treated individuals; however, achievement of sustained unresponsiveness following cessation of therapy has been observed in a smaller subset of treated subjects. The potential therapeutic benefits of OIT must be carefully considered in light of the significant potential for adverse events ranging from self-limited or easily treated oropharyngeal, respiratory or gastrointestinal symptoms, to persistent abdominal complaints that lead to cessation of therapy in an estimated 10-15% of treated individuals. To date, the majority of studies have focused on single-allergen OIT approaches; however, multi-allergen OIT has shown promise in initial trials and is the subject of ongoing investigation to address the complex needs of multi-food allergic individuals. Sublingual immunotherapy (SLIT) has been utilized for the treatment of food allergy and pollen-food allergy syndrome, demonstrating moderate efficacy, a favorable safety profile and variable tolerability, with oropharyngeal symptoms most commonly observed. Although studies directly comparing OIT and SLIT are limited, in general, the favorable safety profile associated with SLIT comes at the expense of reduced efficacy, while the more robust clinical effects observed with OIT come at the risk of potentially intolerable, treatment-limiting side effects. Future investigation to address specific knowledge gaps including optimal dose, duration, age of initiation, maintenance schedule, mechanisms, predictors of risk and therapeutic response will be important to maximize efficacy, minimize risk and develop personalized, effective approaches to targeting food allergy.

Stepwise oral immunotherapy for 10 days in an egg-white allergy mouse model did not ameliorate the severity of allergy but induced the production of allergen-specific IgA

We examined whether the stepwise oral immunotherapy (OIT) for 10 days ameliorates the severity of allergy and the biomarkers in an allergy mouse model. The OIT could not protect anaphylaxis symptoms after allergen challenges but promote the production of antibodies, especially allergen-specific IgA. It was suggested that this OIT influenced the function of immuno response against the allergen. Abbreviations: EW: egg white; IFC: intraperitoneal food challenge; IFN-γ: interferon-γ; IL: interleukin; OVA: ovalbumin; OM: ovomucoid; OFC: oral food challenge; OIT: oral immunotherapy.

New modalities of allergen immunotherapy

Allergen immunotherapy is a rapidly evolving field. Although subcutaneous immunotherapy has been practiced for over a hundred years, improved understanding of the underlying immunological mechanisms has led to the development of new, efficacious and better tolerated allergen-derivatives, adjuvants and encapsulated allergens. Diverse routes of allergen immunotherapy - oral, sublingual, epicutanoeus and intralymphatic - are enabling immunotherapy for anaphylactic food allergies and pollen-food allergy syndrome, while improving the tolerability and effectiveness of aeroallergen immunotherapy. The addition of Anti-IgE therapy decreases adverse effects of subcutaneous and oral immunotherapy.

Clinical and immunological profile of children aged 5-9 years with persistent egg allergy before oral immunotherapy with egg. A multicenter, randomized controlled trial of the Spanish Society of Pediatric Allergy, Asthma and Clinical Immunology (SEICAP)

BACKGROUND

In children with egg protein allergy (EA), the probability of overcoming the allergy decreases with age, and the possibility of suffering severe adverse reactions as a consequence of dietetic transgressions results in worsened quality of life. One treatment option in such cases is oral immunotherapy (OIT) with foods.

METHODS

We present a cohort of children with EA scheduled for OIT with pasteurized raw egg white, describing their clinical and allergic characteristics before the start of OIT.

RESULTS

The median age was six years, and 93% of the patients also suffered other allergies (58% asthma and 38.6% allergy to more than two food groups). In the last year, 14.8% had suffered a severe reaction due to dietetic transgression with egg. The median IgE specific of egg white titer was 38.5kU/l. A double-blind placebo-controlled food challenge with cooked egg white was performed, and if the test proved positive, it was repeated with pasteurized raw egg white. The mean symptoms-provoking dose was 1.26g and 0.55g for cooked egg white and raw egg white, respectively. An IgE specific of ovomucoid titer of <2.045kU/l differentiated those patients that tolerated cooked egg white.

CONCLUSIONS

OIT with egg is regarded as an option in patients with persistent egg allergy. In the previous challenge test, an IgE specific of ovomucoid titer of <2.045kU/l differentiates those patients that tolerate cooked egg white.

Update on oral immunotherapy for egg allergy

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

Oral and sublingual immunotherapy for egg allergy

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Oral immunotherapy in children with IgE-mediated hen's egg allergy: Follow-ups at 2.5 and 7 years

Background:

The present report was a follow-up investigation at 2.5- and 7-year intervals of a previous study of 20 children with moderate-to-severe immunoglobulin E (IgE) mediated hen's egg (HE) allergy who received oral immunotherapy (OIT) with raw HE. The study design of the previous study divided the 20 subjects into two groups of 10 each: (1) group 1, the OIT group (OIT-G), and, (2) group 2, an age-matched control group (C-G). In that study, 8 of 10 of the children in the OIT-G were successfully desensitized, one child was partially desensitized, and desensitization failed in one child. The aims of the present study were to evaluate the long-term effectiveness and safety profile of OIT with raw HE, and to assess the course and prognostic value of skin-prick tests (SPT) and serum-specific HE-IgEs in this study population.

Methods:

Of the 20 children who were recalled, 2 dropped out, which left 18 to be evaluated. Information on their HE intake was recorded, and SPTs with HE allergen extracts and with raw and hard-boiled HE were performed. Ovomucoid- and ovalbumin-specific IgE levels were also measured.

Results:

At the first (2.5-year) and second (7-year) follow-ups, 87.5% of the children in the OIT-G who tolerated raw HE were still tolerant, whereas the children in the C-G were significantly less tolerant. Overall, cutaneous sensitivity to HE significantly decreased after the 6-month desensitization period and at both follow-ups with regard to the OIT-G but not with regard to the C-G. A significant reduction in serum ovomucoid- and ovalbumin-specific IgE levels was seen in both the OIT-G and the C-G.

Conclusion:

Clinical raw HE tolerance induced by OIT persists over time. Negativization of SPTs could be considered a more reliable prognostic indicator of clinical tolerance to raw HE than the reduction in specific-HE IgE levels. Raw-HE OIT would seem to be a promising method to treat HE allergy.

Oral immunotherapy for food allergy: A Spanish guideline. Egg and milk immunotherapy Spanish guide (ITEMS GUIDE). Part 2: Maintenance phase of cow milk (CM) and egg oral immunotherapy (OIT), special treatment dosing schedules. Models of dosing schedules of OIT with CM and EGG

INTRODUCTION

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

INTRODUCTION

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Randomized controlled trial of oral immunotherapy for egg allergy in Japanese patients

BACKGROUND

Egg allergy is one of the most common food allergies in young children. While oral immunotherapy (OIT) is not routinely recommended in current guidelines, it has been considered as a potential alternative treatment strategy. Studies on OIT for food allergy have been explored, but no controlled trials have been reported in Japan.

METHODS

The first oral food challenge (OFC) was performed before treatment to ensure diagnosis and evaluate the threshold dose for egg using the double-blind, placebo-controlled food challenge. Participants were randomly assigned by computerized algorithm to receive OIT using egg (OIT group) or no egg (egg elimination [EE] group). A second OFC was performed in both groups approximately 6 months after therapy. Blood samples were collected and egg white-specific immunoglobulin (Ig)E and IgG4 were measured before and after the treatment period.

RESULTS

Eight of the 14 patients (57%) in the OIT group had no allergic reaction to 4 g dry egg powder whereas none of the 16 patients in the EE group did. All 14 patients in the OIT group had increased threshold for egg powder in the second OFC compared with baseline. There was no significant change in egg white-specific IgE level during therapy. After therapy, egg white-specific IgG4 increased significantly in the OIT group, but not in the EE group.

CONCLUSION

OIT is effective in increasing the threshold for allergens and inducing desensitization in Japanese egg allergy patients, similarly to North American and European patients.

Active treatment for food allergy

Food allergy has grown in rapidly in prevalence, currently affecting 5% of adults and 8% of children. Management strategy is currently limited to 1) food avoidance and 2) carrying and using rescue intramuscular epinephrine/adrenaline and oral antihistamines in the case of accidental ingestion; there is no FDA approved treatment. Recently, oral, sublingual and epicutaneous immunotherapy have been developed as active treatment of food allergy, though none have completed phase 3 study. Efficacy and safety studies of immunotherapy have been variable, though there is clearly signal that immunotherapy will be a viable option to desensitize patients. The use of bacterial adjuvants, anti-IgE monoclonal antibodies, and Chinese herbal formulations either alone or in addition to immunotherapy may hold promise as future options for active treatment. Active prevention of food allergy through early introduction of potentially offending foods in high-risk infants will be an important means to slow the rising incidence of sensitization.

Markers of tolerance development to food allergens

IgE-mediated reactions to food allergens are the most common cause of anaphylaxis in childhood. Although allergies to cow's milk, egg, or soy proteins, in contrast to peanut and tree nut allergens, resolve within the first 6 years of life in up to 60% due to natural tolerance development, this process is not well understood. At present, there is no cure or treatment for food allergy that would result in an induction of tolerance to the symptom-eliciting food. Avoidance, providing an emergency plan and education, is the standard of treatment. Oral immunotherapeutic approaches have been proven reasonable efficacy; however, they are associated with high rates of side-effects and low numbers of patients achieving tolerance. Nevertheless, mechanisms that take place during oral immunotherapy may help to understand tolerance development. On the basis of these therapeutic interventions, events like loss of basophil activation and induction of regulatory lymphocyte subsets and of blocking antibodies have been described. Their functional importance at a clinical level, however, remains to be investigated in detail. Consequently, there is eminent need to understand the process of tolerance development to food allergens and define biomarkers to develop and monitor new treatment strategies for food allergy.

Rush Oral Immunotherapy Does Not Reduce Allergic Response in Mice with Mild Allergy to Egg White Ovomucoid

Oral immunotherapy (OIT) is a promising therapeutic approach for treating food allergy. Past studies have shown that OIT reduces allergic response only in severe allergy model mice. We worked to establish mild allergy model mice, and investigated whether 'rush' OIT for 10 d improved the allergic response and biomarkers in these mice. Balb/c mice were sensitized to ovomucoid (OM) in alum. The rush OIT was done for 10 d. Oral OM challenge was used to determine the impact of OIT on the allergic response. We measured allergic biomarkers, such as vascular permeability in the skin, plasma levels of total IgE, OM-specific IgE, IgG1 and IgG2a and cytokines in splenocyte culture supernatant. OIT for 10 d did not improve allergy symptoms and increased vascular permeability. Total IgE in the plasma of OIT-treated mice was significantly higher than in that of non-treated mice. OM-specific IgG1 and IgG2a plasma levels were not significantly different between OIT-treated and non-treated mice. Among the cytokine secretion of splenocyte from OIT-treated mice, IFN-γ and IL-10 were significantly lower than in non-treated mice, and IL-4 and IL-5 were significantly higher. Total TGF-β in the OIT-treated group was not detected. The IFN-γ/IL-4 ratio of the OIT-treated group was about 1/8 that of the non-treated group. OIT for 10 d was not effective and some biomarkers showed negative responses in the mild allergy model mice. We suggest OIT should be used very carefully as this treatment carries a risk of worsening allergy symptoms for mice with mild allergy.

Early sustained unresponsiveness after short-course egg oral immunotherapy: a randomized controlled study in egg-allergic children

BACKGROUND

No studies have evaluated the potential of egg oral immunotherapy (egg-OIT) to induce sustained unresponsiveness after discontinuing therapy following short-term treatments.

OBJECTIVE

We assessed the efficacy of short-course egg-OIT to induce sustained unresponsiveness.

METHODS

Sixty-one egg-allergic children, 5 to 17 years old, with positive double-blind placebo-controlled food challenge (DBPCFC) to dehydrated egg white (EW) were randomized to receive egg-OIT (OITG) for 3 months (maintenance dose one undercooked egg every 48 hours) or to continue egg avoidance diet (control group, CG) for 4 months. Children who completed egg-OIT avoided egg for 1 month. At 4 months, both groups underwent a DBPCFC. OITG participants who passed this challenge were instructed to add egg to their diet ad libitum. Immune markers were studied at different time points.

RESULTS

Ninety-three percent (28/30) of OITG children were desensitized in a median of 32.5 days (IQR, 14 days). At 4 months, 1/31 (3%) in CG passed DBPCFC and 11/30 (37%) of OITG (95% CI, 14 to 51%; P = 0.003), all of them were consuming egg at 36 months. A decrease in EW, OVA and OVM skin test results and OVA-specific IgE (sIgE) levels was observed on OITG at 4 months (P = 0.001). EW-, OVA- and OVM-sIgE levels prior to the start of egg avoidance diet were lower in OITG children who passed DBPCFC at 4 months than in those who did not pass it. EW- and OVM-sIgE showed the best diagnostic performance in predicting DBPCFC result at 4 months. Levels above optimal EW-sIgE cut-off of 7.1 kU/L indicated 90% probability of failing DBPCFC.

CONCLUSION

This is the first demonstration of sustained unresponsiveness with a three-month egg-OIT protocol. Almost all treated subjects were desensitized and 37% achieved sustained unresponsiveness. EW-sIgE levels at the end of treatment predicted sustained unresponsiveness. This protocol shows a new approach to OIT for egg-allergic children.

Oral Immunotherapy for Food Allergy

Food allergy is a potentially life-threatening condition with no approved therapies, apart from avoidance and injectable epinephrine for acute allergic reactions. Oral immunotherapy (OIT) is an experimental treatment in which food-allergic patients consume gradually increasing quantities of the food to increase their threshold for allergic reaction. This therapy carries significant risk of allergic reactions. The ability of OIT to desensitize patients to particular foods is well-documented, although the ability to induce tolerance has not been established. This review focuses on recent studies for the treatment of food allergies such as cow's milk, hen's egg, and peanut.

Food specific oral immunotherapy: a potential treatment for food allergy

Food allergy is a potentially life-threatening condition affecting up to 8% of children and up to 2% of adults in westernized countries. There are currently no approved treatments for food allergy apart from avoidance. The apparent increase in incidence of food allergies over the past few decades calls attention to the need for effective, disease-modifying therapies for food allergies. Oral immunotherapy (OIT) is a promising experimental treatment in which food allergic patients consume increasing quantities of food in attempt to increase their threshold for allergic reaction. Studies are ongoing to determine whether OIT is capable of safely inducing not only desensitization but also tolerance to the allergenic foods. This article focuses on recent relevant studies of OIT for the treatment of common food allergies.

Differential response in allergen-specific IgE, IgGs, and IgA levels for predicting outcome of oral immunotherapy

BACKGROUND

Oral immunotherapy (OIT) induces desensitization and/or tolerance in patients with persistent food allergy, but the biomarkers of clinical outcomes remain obscure. Although OIT-induced changes in serum allergen-specific IgE and IgG4 levels have been investigated, the response of other allergen-specific IgG subclasses and IgA during OIT remains obscure.

METHODS

A pilot study was conducted to investigate egg OIT-induced changes in allergen-specific IgE, IgG subclasses, and IgA levels and search for possible prediction biomarkers of desensitization. We measured serum levels of egg white-, ovomucoid-, and ovalbumin-specific IgE, IgA, and IgG subclasses by high-sensitivity allergen microarray in 26 children with egg allergy who received rush OIT.

RESULTS

Allergen-specific IgE gradually decreased while IgG4 increased during 12-month OIT. Serum levels of IgG1, IgG3, and IgA increased significantly after the rush phase, then decreased during the maintenance phase. IgG2 levels changed in a manner similar to that of IgG4. In particular, significantly high fold increases in egg white-specific IgG1, relative to baseline, after the rush phase and high IgA levels before OIT were observed in responders, compared with low-responders to OIT. Patients who could not keep desensitization showed relatively small changes in all immunoglobulin levels during OIT.

CONCLUSION

The response to OIT was associated with significant increases in serum allergen-specific IgG1 levels after rush phase and high baseline IgA levels, compared with small changes in immunoglobulin response in low-responders. The characteristic IgG1 changes and IgA levels in the responders could be potentially useful biomarkers for the prediction of positive clinical response to OIT.

Improving the safety of oral immunotherapy for food allergy

Food allergy is a major public health problem in children, impacting upon the affected individual, their families and others charged with their care, for example educational establishments, and the food industry. In contrast to most other paediatric diseases, there is no established cure: current management is based upon dietary avoidance and the provision of rescue medication in the event of accidental reactions, which are common. This strategy has significant limitations and impacts adversely on health-related quality of life. In the last decade, research into disease-modifying treatments for food allergy has emerged, predominantly for peanut, egg and cow's milk. Most studies have used the oral route (oral immunotherapy, OIT), in which increasing amounts of allergen are given over weeks-months. OIT has proven effective to induce immune modulation and 'desensitization' - that is, an increase in the amount of food allergen that can be consumed, so long as regular (typically daily) doses are continued. However, its ability to induce permanent tolerance once ongoing exposure has stopped seems limited. Additionally, the short- and long-term safety of OIT is often poorly reported, raising concerns about its implementation in routine practice. Most patients experience allergic reactions and, although generally mild, severe reactions have occurred. Long-term adherence is unclear, which rises concerns given the low rates of long-term tolerance induction. Current research focuses on improving current limitations, especially safety. Strategies include alternative routes (sublingual, epicutaneous), modified hypoallergenic products and adjuvants (anti-IgE, pre-/probiotics). Biomarkers of safe/successful OIT are also under investigation.

Immunotherapy for food allergies: a myth or a reality?

Food allergy is a worldwide issue, with an estimated prevalence of 2-10%. An effective treatment is not available for people affected and the only management is the avoidance of the allergen. Oral immunotherapy and sublingual immunotherapy have been tested by several authors, in particular for milk, egg and peanuts allergy, with significant results in term of desensitization induction. The achievement of tolerance is by the contrary doubtful, with different results obtained. In this review, we reviewed protocols of oral and sublingual immunotherapy for food allergy published in literature, mainly against milk, egg and peanut. At present, immunotherapy does not represent the gold standard in the treatment of food allergy, even if it can desensitize patients.

Pharmacologic options for the treatment and management of food allergy

Food allergy affects approximately 5% of adults and 8% of children in developed countries, and there is currently no cure. Current pharmacologic management is limited to using intramuscular epinephrine or oral antihistamines in response to food allergen exposure. Recent trials have examined the efficacy and safety of subcutaneous, oral, sublingual, and epicutaneous immunotherapy, with varying levels of efficacy and safety demonstrated. Bacterial adjuvants, use of anti-IgE monoclonal antibodies, and Chinese herbal formulations represent exciting potential for development of future pharmacotherapeutic agents. Ultimately, immunotherapy may be a viable option for patients with food allergy, although efficacy and safety are likely to be less than ideal.

Oral immunotherapy for the treatment of food allergy

Oral immunotherapy (OIT) is an emerging new therapy for food allergy. With multiple small exploratory trials and some large randomized-controlled phase 2 trials recently published and under way, there is a clear progress and interest toward making this a treatment option for patients suffering from food allergies. However, there are still many questions to be answered and parameters to fine-tune before OIT becomes an accepted option outside of the research setting. This review covers the main milestones in the development of OIT for food allergy and further discusses important specific issues that will have direct impact on its clinical application. More specifically, previous publications showing evidence for the induction of tolerance are specifically reviewed and varying safety, tolerability and efficacy parameters from previous reports are also discussed.

Clinical efficacy and immunological changes subjacent to egg oral immunotherapy

BACKGROUND

Evidence of the efficacy of food oral immunotherapy (OIT) is not robust enough to change clinical practice from current standard management. Furthermore, the immunologic changes underlying food desensitization are unknown.

OBJECTIVE

To establish the immunologic basal status and differences between an egg-allergic group of children and a population of nonallergic children and to investigate the safety and efficacy of a specific egg OIT protocol to induce clinical desensitization and the associated immune responses.

METHODS

Children with or without egg allergy were recruited. Allergic subjects underwent an OIT protocol based on weekly doses of egg protein and a maintenance phase. Immune profile and changes in all subjects were investigated by measuring T-helper cells types 1 and 2 (TH1 and TH2) and T-regulatory cytokines and transcription factors and egg-specific IgE and IgG4 levels.

RESULTS

At baseline, a significantly lower production of ovalbumin-specific interleukin (IL)-10 and tumor necrosis factor-α and a trend toward higher IL-5 and IL-13 were found in allergic children. The egg OIT protocol enabled 60% of them to ingest 32 mL of egg white. Significant increases in egg-specific IgG4 levels and IL-10 production, with a trend toward lower IL-5 and IL-13 and higher tumor necrosis factor-α and interferon-γ levels, and significant decreases in egg-specific IgE concentration were observed.

CONCLUSION

Egg-allergic individuals display a bias toward TH2 type cytokine production and decreased TH1 and IL-10 responses compared with nonallergic individuals. The OIT protocol was safe and effective in inducing egg desensitization, leading to a shift in the immune profile of allergic individuals toward a nonallergic phenotype.

Sublingual (SLIT) versus oral immunotherapy (OIT) for food allergy

Food allergy is a common condition for which the only currently approved treatments are avoidance of the allergenic food and the administration of emergency medications upon accidental exposure. Over the past 10 years, significant advances have been made in the field of food immunotherapy, with efforts focusing on allergen exposure via the oral mucosa. Oral immunotherapy (OIT) and sublingual immunotherapy (SLIT) are the two modalities that have been most extensively studied, and this article will review recent advances in our knowledge of the efficacy and safety of these treatments.

Oral and sublingual immunotherapy for egg allergy

BACKGROUND

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

OBJECTIVES

We aimed to assess the successful desensitization and development of tolerance to egg protein and the safety of egg oral and sublingual immunotherapy in children and adults with immunoglobulin E (IgE)-mediated egg allergy as compared to a placebo treatment or an avoidance strategy.

SEARCH METHODS

We searched 13 databases for journal articles, conference proceedings, theses and unpublished trials using a combination of subject headings and text words (the last search was on 5 December 2013).

SELECTION CRITERIA

Randomized controlled trials (RCTs) were included. All age groups with clinical egg allergy were to be included.

DATA COLLECTION AND ANALYSIS

We retrieved 83 studies from the electronic searches. We selected studies, extracted data and assessed the methodological quality. We attempted to contact the study investigators to obtain the unpublished data, wherever possible. We used the I² statistic to assess statistical heterogeneity. We estimated a pooled risk ratio (RR) with 95% confidence interval (CI) for each outcome using a Mantel-Haenzel fixed-effect model if statistical heterogeneity was low (I² value less than 50%).

MAIN RESULTS

We included four RCTs with a total of 167 recruited individuals (OIT 100; control 67 participants), all of whom were children (aged four to 15 years). One study used a placebo and three studies used an avoidance diet as the control. Each study used a different OIT protocol. Thirty nine per cent of OIT participants were able to tolerate a full serving of egg compared to 11.9% of the controls (RR 3.39, 95% CI 1.74 to 6.62). Forty per cent of OIT participants could ingest a partial serving of egg (1 g to 7.5 g; RR 5.73, 95% CI 3.13 to 10.50). Sixty nine per cent of the participants presented with mild-to-severe adverse effects (AEs) during OIT (RR 6.06, 95% CI 3.11 to 11.83). Five of the 100 participants receiving OIT required epinephrine. We cannot comment on whether over- or under-reporting of AEs was a concern based on the available data. Overall there was inconsistent methodological rigour in the trials.

AUTHORS' CONCLUSIONS

The studies were small and the quality of evidence was low. Current evidence suggests that OIT can desensitize a large number of egg-allergic patients, although it remains unknown whether long-term tolerance develops. A major difficulty of OIT is the frequency of AEs, though these are usually mild and self-limiting. The use of epinephrine while on OIT seems infrequent. There are no standardized protocols for OIT and guidelines would be required prior to incorporating desensitization into clinical practice.

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.

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.

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.

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.

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.

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.

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

Position document: IgE-mediated allergy to egg protein

Egg is the food that most often causes allergy in young Spanish children, with an incidence of 2.4-2.6% in the first 2 years of life. The prevalence of sensitisation and allergy to egg is greater in children with allergy to cow's milk and in those suffering atopic dermatitis. The protein component from egg white is the cause of the allergic response in child. The major allergens in egg white are ovomucoid and ovalbumin. Most of the allergic reactions affect the skin, followed by gastrointestinal and respiratory systems. Egg allergy is one of the most common causes of severe anaphylaxis. The diagnosis of egg allergy is based on the existence of a suggestive clinical history, a positive allergy study and the subsequent application of controlled exposure testing, which represents the gold standard for confirming the diagnosis. The treatment of egg allergy is based on the avoidance of egg protein intake. A subgroup of egg-allergic patients are tolerant to cooked egg. In these cases, only uncooked egg must necessarily be avoided. Maintaining a diet with strict egg avoidance is difficult, and transgressions are relatively common. The patient, family, and school environment should receive education and training in the avoidance of egg and in the management of possible allergic reactions. With an avoidance diet, up to 15-20% of children will remain allergic and the severity of the reactions will increase over the years. In these more severe cases of egg-allergy, it becomes more difficult to adhere to the avoidance diet over the years, with a significant decrease in patient quality of life. Oral tolerance induction can be regarded as a therapeutic option for IgE-mediated egg allergy. The anti-IgE, omalizumab, might become another genuine therapeutic option for food allergy, not only to prevent allergic reactions after a contact with egg, but also as a complementary treatment to oral tolerance induction for egg allergy, with the purpose of reducing adverse reactions. The administration of influenza vaccine to children with egg allergy is safe in children that do not manifest severe reactions after egg intake, and in children who tolerate cooked egg. The triple viral vaccine (MMR) can be given to egg-allergic children in their usual vaccination centre, with no added risk. Different medicinal products can be formulated with egg proteins, and therefore should be avoided in children with egg allergy.

Heated allergens and induction of tolerance in food allergic children

Food allergies are one of the first manifestations of allergic disease and have been shown to significantly impact on general health perception, parental emotional distress and family activities. It is estimated that in the Western world, almost one in ten children have an IgE-mediated allergy. Cow's milk and egg allergy are common childhood allergies. Until recently, children with food allergy were advised to avoid all dietary exposure to the allergen to which they were sensitive, in the thought that consumption would exacerbate their allergy. However, recent publications indicate that up to 70% of children with egg allergy can tolerate egg baked in a cake or muffin without apparent reaction. Likewise, up to 75% of children can tolerate baked goods containing cow's milk, and these children demonstrate IgE and IgG4 profiles indicative of tolerance development. This article will review the current literature regarding the use of heated food allergens as immunotherapy for children with cow's milk and egg allergy.