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Omalizumab for the Treatment of Multiple Food Allergies

Author/s: 
Wood RA, Togias A, Sicherer SH, Shreffler WG, Kim EH, Jones SM

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

RESULTS
Of the 462 persons who were screened, 180 underwent randomization. The analysis population consisted of the 177 children and adolescents (1 to 17 years of age). A total of 79 of the 118 participants (67%) receiving omalizumab met the primary end-point criteria, as compared with 4 of the 59 participants (7%) receiving placebo (P<0.001). Results for the key secondary end points were consistent with those of the primary end point (cashew, 41% vs. 3%; milk, 66% vs. 10%; egg, 67% vs. 0%; P<0.001 for all comparisons). Safety end points did not differ between the groups, aside from more injection-site reactions in the omalizumab group.
CONCLUSIONS
In persons as young as 1 year of age with multiple food allergies, omalizumab treatment for 16 weeks was superior to placebo in increasing the reaction threshold for peanut and other common food allergens. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT03881696.)

Management of Food Allergies and Food-Related Anaphylaxis

Author/s: 
Edward G A Iglesia, Mildred Kwan, Yamini V Virkud, Onyinye I Iweala

Importance: An estimated 7.6% of children and 10.8% of adults have IgE-mediated food-protein allergies in the US. IgE-mediated food allergies may cause anaphylaxis and death. A delayed, IgE-mediated allergic response to the food-carbohydrate galactose-α-1,3-galactose (alpha-gal) in mammalian meat affects an estimated 96 000 to 450 000 individuals in the US and is currently a leading cause of food-related anaphylaxis in adults.

Observations: In the US, 9 foods account for more than 90% of IgE-mediated food allergies-crustacean shellfish, dairy, peanut, tree nuts, fin fish, egg, wheat, soy, and sesame. Peanut is the leading food-related cause of fatal and near-fatal anaphylaxis in the US, followed by tree nuts and shellfish. The fatality rate from anaphylaxis due to food in the US is estimated to be 0.04 per million per year. Alpha-gal syndrome, which is associated with tick bites, is a rising cause of IgE-mediated food anaphylaxis. The seroprevalence of sensitization to alpha-gal ranges from 20% to 31% in the southeastern US. Self-injectable epinephrine is the first-line treatment for food-related anaphylaxis. The cornerstone of IgE-food allergy management is avoidance of the culprit food allergen. There are emerging immunotherapies to desensitize to one or more foods, with one current US Food and Drug Administration-approved oral immunotherapy product for treatment of peanut allergy.

Conclusions and relevance: IgE-mediated food allergies, including delayed IgE-mediated allergic responses to red meat in alpha-gal syndrome, are common in the US, and may cause anaphylaxis and rarely, death. IgE-mediated anaphylaxis to food requires prompt treatment with epinephrine injection. Both food-protein allergy and alpha-gal syndrome management require avoiding allergenic foods, whereas alpha-gal syndrome also requires avoiding tick bites.

Keywords 
Alpha-Gal Syndrome Anaphylaxis Food Allergies Food Allergy nuts Shellfish

Timing of Allergenic Food Introduction and Risk of Immunoglobulin E-Mediated Food Allergy: A Systematic Review and Meta-analysis

Author/s: 
Scarpone, R., Kimkool, P., Ierodiakonou, D., Leonardi-Bee, J., Garcia-Larsen, V., Perkin, M. R., Boyle, R. J.

Importance: Earlier egg and peanut introduction probably reduces risk of egg and peanut allergy, respectively, but it is uncertain whether food allergy as a whole can be prevented using earlier allergenic food introduction.

Objective: To investigate associations between timing of allergenic food introduction to the infant diet and risk of food allergy.

Data sources: In this systematic review and meta-analysis, Medline, Embase, and CENTRAL databases were searched for articles from database inception to December 29, 2022. Search terms included infant, randomized controlled trial, and terms for common allergenic foods and allergic outcomes.

Study selection: Randomized clinical trials evaluating age at allergenic food introduction (milk, egg, fish, shellfish, tree nuts, wheat, peanuts, and soya) during infancy and immunoglobulin E (IgE)-mediated food allergy from 1 to 5 years of age were included. Screening was conducted independently by multiple authors.

Data extraction and synthesis: The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was used. Data were extracted in duplicate and synthesized using a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation framework was used to assess certainty of evidence.

Main outcomes and measures: Primary outcomes were risk of IgE-mediated allergy to any food from 1 to 5 years of age and withdrawal from the intervention. Secondary outcomes included allergy to specific foods.

Results: Of 9283 titles screened, data were extracted from 23 eligible trials (56 articles, 13 794 randomized participants). There was moderate-certainty evidence from 4 trials (3295 participants) that introduction of multiple allergenic foods from 2 to 12 months of age (median age, 3-4 months) was associated with reduced risk of food allergy (risk ratio [RR], 0.49; 95% CI, 0.33-0.74; I2 = 49%). Absolute risk difference for a population with 5% incidence of food allergy was -26 cases (95% CI, -34 to -13 cases) per 1000 population. There was moderate-certainty evidence from 5 trials (4703 participants) that introduction of multiple allergenic foods from 2 to 12 months of age was associated with increased withdrawal from the intervention (RR, 2.29; 95% CI, 1.45-3.63; I2 = 89%). Absolute risk difference for a population with 20% withdrawal from the intervention was 258 cases (95% CI, 90-526 cases) per 1000 population. There was high-certainty evidence from 9 trials (4811 participants) that introduction of egg from 3 to 6 months of age was associated with reduced risk of egg allergy (RR, 0.60; 95% CI, 0.46-0.77; I2 = 0%) and high-certainty evidence from 4 trials (3796 participants) that introduction of peanut from 3 to 10 months of age was associated with reduced risk of peanut allergy (RR, 0.31; 95% CI, 0.19-0.51; I2 = 21%). Evidence for timing of introduction of cow's milk and risk of cow's milk allergy was very low certainty.

Conclusions and relevance: In this systematic review and meta-analysis, earlier introduction of multiple allergenic foods in the first year of life was associated with lower risk of developing food allergy but a high rate of withdrawal from the intervention. Further work is needed to develop allergenic food interventions that are safe and acceptable for infants and their families.

Keywords 
Shellfish nuts Food Allergies allergen introduction egg

Food Allergy Prevention: Early Versus Late Introduction of Food Allergens in Children

Author/s: 
Djossi, S. K., Khedr, A., Neupane, B., Proskuriakova, E., Jada, K., Mostafa, J. A.

The emergence of food allergies in children is crucial for various medical fields seeking a viable strategy for allergy prevention. The most well-recognized approach adopted by numerous health care and government institutions hinges on the delay in the introduction of food allergens, which supposedly protects infants from sensitization and decreases the possibility of allergy development. However, recent experimental findings indicate that the benefits of this approach might be overestimated, as early exposure to allergenic foods has been shown to yield more advantageous outcomes. Multiple investigations on the causes of allergic diseases report that avoiding food allergies might be related to early consumption of these allergens. Alternatively, delaying the contact with allergenic nourishments, explored in contemporary research, has been proven to result in a higher prevalence of allergies among children, originating such conditions as atopic diseases and extreme sensitization to foods. The current paper compares the two prominent strategies of allergenic food introduction, gathering the most pertinent modern evidence to distinguish whether exposure to food allergens should be delayed or advanced.

Keywords 
Food Allergy children Allergens Allergy Prevention

The Role of Immunotherapy in the Treatment of Asthma

Author/s: 
Lin, Sandra Y., Azar, Antoine, Suarez-Cuervo, Catalina, Diette, Gregory B., Brigham, Emily, Rice, Jessica, Ramanathan, Murugappan Jr., Gayleard, Jessica, Robinson, Karen A.

Objectives. To evaluate the efficacy and safety of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) in the treatment of allergic asthma.

Data Sources. We searched PubMed, Embase, and CENTRAL through May 8, 2017.

Methods. Two reviewers independently selected randomized controlled trials (RCTs) of the efficacy of SCIT and SLIT and RCTs, observational studies, and case series or case reports on safety. Two reviewers independently assessed the risk of bias for each study and together graded the strength of the evidence.

Results. We identified 54 RCTs on efficacy: 31 assessed SCIT and 18 assessed SLIT and 5 on SCIT versus SLIT. We included 80 studies on safety: 26 RCTs and 18 non-RCTs for SCIT, 20 RCTs and 10 non-RCTs for SLIT and one non-RCT on SCIT versus SLIT.

SCIT reduces the use of long-term control medications [moderate strength of evidence (SOE)]. SCIT may improve quality of life, reduce the use of quick-relief medications (short-acting bronchodilators), reduce the need for systemic corticosteroids, and improve FEV1 (low SOE). There was insufficient evidence regarding the effect of SCIT on asthma symptoms and health care utilization. Local and systemic allergic reactions were frequent but infrequently required a change in treatment. We are unable to draw conclusions about whether SCIT increased risk of anaphylaxis, primarily because anaphylaxis was not directly measured (insufficient SOE). There was one case report of a death determined possibly to be caused by SCIT.

SLIT improves asthma symptoms (high SOE); decreases use of long-term control medication and improves FEV1 (moderate SOE). SLIT may decrease quick-relief medication use, and may improve quality of life (low SOE). There was insufficient evidence about the effect of SLIT on systemic corticosteroid use and health care utilization. Local and systemic allergic reactions were common but infrequently required changes in treatment. Life-threatening reactions were not commonly reported, with three case reports of anaphylaxis (insufficient SOE) and no deaths (moderate SOE) reported.

There was insufficient evidence to draw conclusions about the comparative effects of SCIT versus SLIT or for differential effects of immunotherapy based on patient age, setting of administration, or type of allergen.

Conclusions. Overall, SLIT and SCIT were beneficial for the majority of asthma-related outcomes assessed in this report. Local and systemic allergic reactions were common but infrequently required changes in treatment. Life-threatening events (such as anaphylaxis) were reported rarely.

Keywords 
asthma SLIT SCIT subcutaneous immunotherapy sublingual immunotherapy
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