November/December 2019 Issue

Food Allergies/Sensitivities: Will Food Allergies Soon Be Eliminated?
By Sherry Coleman Collins, MS, RDN, LD
Today’s Dietitian
Vol. 21, No. 11, P. 12

New treatments may be on the horizon that could potentially offer such promise.

Are we on the cusp of a cure for food allergies? While the answer may not be “yes” yet, innovative treatments currently being researched may be available soon, giving food-allergic individuals more options. At this point, the only real treatment involves complete avoidance of the allergen and rescue medications in case of ingestion. According to a 2017 report by the National Institutes of Health, the true prevalence of food allergies is unknown, but it’s estimated to be 2% to 10% of Americans.1 The most common food allergens in the United States are milk, egg, peanut, tree nut, fish, crustacean shellfish, wheat, and soy. Most food allergy treatment research has focused on peanut, milk, and egg.2-4

In this article, Today’s Dietitian (TD) digs into the latest research on emerging treatments for food allergies that could increase tolerance, reduce the risk of life-threatening reactions, and potentially eliminate allergies altogether. TD also will discuss opportunities for dietitians to work with patients and on treatment teams in research and ongoing care.

Immunotherapy

Oral Immunotherapy
Oral immunotherapy (OIT) is widely considered to be the most promising form of treatment being researched. During treatment, patients eat tiny and increasing doses of the allergen over a period of months or years to achieve a target daily dose. How the protein is eaten differs based on the allergen and the protocol of the study. Peanut protein most often is ingested in the form of defatted peanut flour that’s measured and mixed into another food such as applesauce. Milk or egg protein may be fed similarly or in baked form, such as in a muffin, since extensive high heat changes the structure of the protein and may improve tolerability.2

The goal of OIT is to raise the threshold of tolerance or desensitize the individual to the allergen. Many studies have been published on the use of OIT for treating peanut, milk, and egg allergies, and it has shown efficacy of 50% to 93%, 36% to 90%, and 57% to 75%, respectively.3 The wide variation in success rates reflects differences among studies’ protocols and goals.

OIT frequently causes reactions, and some have been severe.3,5 The most common reactions include gastrointestinal symptoms. However, anaphylaxis has occurred. Illness, exercise, and menses increase the risk of anaphylaxis, even with previously tolerated doses, so individuals must be prepared to treat severe reactions with epinephrine at home or in the doctor’s office.2,3 OIT also increases the risk of developing eosinophilic esophagitis (EoE).3 EoE is a condition in which the lining of the esophagus thickens and becomes rough, ridged, and infiltrated with eosinophils (specialized immune cells), making swallowing difficult. EoE is hard to manage and can be long lasting and recurrent.

OIT Plus Other Treatments
In some studies, researchers are looking at what happens when you combine OIT with other treatments, such as biologics (ie, drugs produced from living organisms or that contain parts of living organisms) or probiotics (ie, microbes that confer a positive benefit to the host). While there are limited published studies in this area, it seems promising because combination therapy helps address some of the side effects while enhancing the action of OIT.

Omalizumab (brand name Xolair) is a “recombinant, humanized, monoclonal antibody” capable of binding to immunoglobulin E (IgE). In binding to free, unbound IgE, omalizumab reduces the amount of IgE available to participate in allergic reactions.6 Therefore, the contribution omalizumab makes in a combined therapy is to increase safety and reduce symptoms. Omalizumab has been used in conjunction with OIT and as a monotherapy. In one small study of children with concurrent multifood allergy and asthma, omalizumab increased food tolerance significantly even without the use of OIT. Omalizumab has shown benefit, but more research is needed.7,8

Studies have shown differences in the microbiomes in children who develop food allergies compared with those without food allergies; therefore, manipulation of the microbiome may make treatments more effective. In one study, researchers compared peanut OIT plus a probiotic (Lactobacillus rhamnosus CGMCC 1.3724) with placebo OIT and found that 82% of the treatment group was desensitized.9 However, more research is needed because this was a small group and researchers didn’t compare it with OIT alone.

Epicutaneous Immunotherapy
Epicutaneous immunotherapy (EPIT) is performed using a patch permeated with allergenic protein to expose the allergic individual to tiny amounts of proteins through the skin for a specific number of hours each day. Minute amounts of the proteins are absorbed through the skin and desensitize patients to the allergen over the course of months or years. EPIT has been studied to treat peanut and milk allergy.4

EPIT has a favorable safety profile with no severe reactions reported.4 The most common side effect is skin irritation at the site of the patch. Studies have shown that EPIT is more effective than placebo; however, the change in tolerance to allergens using EPIT is in the range of only micrograms as opposed to milligrams for OIT.2

Sublingual Immunotherapy
Sublingual immunotherapy (SLIT) involves placing drops of the allergen in a liquid suspension under the tongue, which is held for a couple of minutes before swallowing. This administration is performed in increasing doses daily. The treatment is significantly less effective than OIT, yet SLIT has been shown to be effective in 10% to 70% of studies on food allergy, including peanut, hazelnut, and milk.3 Of particular interest with SLIT is the fact that adverse reactions are generally mild and its efficacy is similar to that of EPIT.5 Research is limited, and more is needed to evaluate its full potential as a treatment option.

Other Potential and Emerging Treatments
There are several other possible treatments currently being studied, which are considered potential “next-generation” therapies for food allergies. For instance, intradermal or intramuscular treatments that work similarly to vaccines are in phase 1 trials at this time. Another potential treatment uses killed E coli to deliver modified proteins rectally with the goal of inducing tolerance; however, this treatment had a poor safety profile in early trial.5

Role of RDs
In the world of food allergy research, RDs play an important role. The European Academy of Allergy & Clinical Immunology recently published a paper highlighting the important roles of allied health professionals, including allergy specialist dietitians, in the care of individuals with food allergies.10 RDs can assist families in determining whether treatment is the right option for them. In some cases, the treatment may be worse or more difficult than managing the allergy itself and requires self-awareness and commitment, according to Alexia Beauregard, MS, RD, CSP, LD, a faculty member at Ellyn Satter Institute and a clinical dietitian at Winn Army Community Hospital in Fort Stewart, Georgia. RDs can help by asking questions such as “What is the individual/family’s ability to cook?”; “Do they have resources to buy special food?”; “Are they likely to attend regular clinic appointments?”; “Can they read, speak, and understand instructions in English?”; and “Are they able to seek emergency treatment in the event of an adverse reaction while at home during treatment?”

Marion Groetch, MS, RDN, director of nutrition services at the Jaffe Food Allergy Institute at Icahn School of Medicine at Mount Sinai in New York, says, “Dietitians have a food science background and skill that makes them uniquely qualified to create safe dosing protocols.” She and her colleague Allison Schaible, MS, RDN, clinical nutrition coordinator at the Jaffe Food Allergy Institute, say that RDs can provide support to patients and other clinical team members to ensure the most successful course of treatment possible. She says, “The RDN’s role ensures safely preparing oral food challenges, educating patients on home introduction of allergens—or, alternatively, avoidance—researching food products and advising on safe food choices, and contributing to the development of food allergy research protocols.”

RDs are essential to helping provide context for food-allergic individuals participating in treatment and otherwise. Patients and families need to understand how to continue their treatment after “graduating” from a research study, as failure to continue treatment may result in reduced tolerance and increased risk of reactions.3 RDs are the health care providers on the team who can help liberalize diets, teach safe food choice and cooking techniques, and help prevent nutrient deficiencies.11 If the patient or family choose not to pursue or decide to discontinue treatment, the RD is an essential provider of MNT for managing food allergies.

Future Opportunities
For RDs interested in the treatment and management of food allergies, there are and will continue to be ongoing opportunities to expand practice and knowledge. It’s anticipated that one or more treatment options could be approved by the FDA as soon as 2020.12 Currently, potential treatments aren’t considered curative and will require significant effort for potentially life-long adherence to treatment protocols, continued dietary intervention that still may involve a level of avoidance, and preparation to treat potentially severe reactions.3 Because of the unique understanding of food science, culinary application, and nutrition needs, RDs are an important part of the team in research and clinical care.

— Sherry Coleman Collins, MS, RDN, LD, is president of Southern Fried Nutrition Services in Atlanta, specializing in food allergies and sensitivities, digestive disorders, and nutrition communications. Find her on Twitter, Instagram, and Facebook as @DietitianSherry, via the Southern Fried Girlfriends podcast, and at www.southernfriednutrition.com.

References
1. National Academies of Sciences, Engineering, and Medicine. Finding a path to safety in food allergy: assessment of the global burden, causes, prevention, management, and public policy. https://www.nap.edu/read/23658/chapter/1. Published 2017. Accessed September 3, 2019.

2. Jones SM, Burks AW, Dupont C. State of the art on food allergen immunotherapy: oral, sublingual, and epicutaneous. J Allergy Clin Immunol. 2014;133(2):318-323.

3. Wood RA. Food allergen immunotherapy: current status and prospects for the future. J Allergy Clin Immunol. 2016;137(4):973-982.

4. Burks AW, Sampson HA, Plaut M, Lack G, Akdis CA. Treatment for food allergy. J Allergy Clin Immunol. 2018;141(1):1-9.

5. Vickery BP, Ebisawa M, Shreffler WG, Wood RA. Current and future treatment of peanut allergy. J Allergy Clin Immunol Pract. 2019;7(2):357-365.

6. Godse K, Mehta A, Patil S, Gautam M, Nadkarni N. Omalizumab — a review. Indian J Dermatol. 2015;60(4):381-384.

7. Fiocchi A, Artesani MC, Riccardi C, et al. The impact of omalizumab on food allergy in patients treated for asthma: a real-life study. J Allergy Clin Immunol Pract. 2019;7(6):1901-1909.

8. Vickery B. Can omalizumab monotherapy benefit real-world food allergy patients? Lessons from an observational study. J Allergy Clin Immunol Pract. 2019;7(6):1910-1911.

9. Tang ML, Ponsonby AL, Orsini F, et al. Administration of a probiotic with peanut oral immunotherapy: a randomized trial. J Allergy Clin Immunol. 2015;135(3):737-744.e8.

10. Skypala IJ, de Jong NW, Angier E, et al. Promoting and achieving excellence in the delivery of integrated allergy care: the European Academy of Allergy & Clinical Immunology competencies for allied health professionals working in allergy. Clin Transl Allergy. 2018;8:31.

11. Collins SC. Practice paper of the Academy of Nutrition and Dietetics: role of the registered dietitian nutritionist in the diagnosis and management of food allergies. J Acad Nutr Diet. 2016;116(10):1621-1631.

12. The current state of oral immunotherapy (OIT) for the treatment of food allergy. American Academy of Allergy, Asthma & Immunology website. https://www.aaaai.org/conditions-and-treatments/library/allergy-library/oit. Updated September 14, 2019.