Does oral immunotherapy work?

Oral immunotherapy is gaining ground as a way to treat and manage food allergies, but there are a number of considerations that should be made by clinicians before beginning a treatment plan.

Food allergies affect up to 10% of the population in developed countries, according to a new report¹ in the Journal of Allergy and Clinical Immunology, and accidental exposures to allergens in foods can cause dangerous reactions. Although anaphylaxis from exposure to a food allergen is concerning, new therapies involve using those same allergens through carefully monitored exposures to reduce sensitivity and potentially overcome food allergies. For example, oral immunotherapy has gained ground in recent years, particularly in the treatment of peanut allergies.

Although oral immunotherapy has shown success in treating food allergies, it also comes with risks, and attempts to overcome food allergies through this method require close supervision and considerable preparation.

Lead author Will Thomas B. Casale, MD, chief medical advisor for operations at the Food Allergy Research and Education (FARE) program and professor of medicine and pediatrics at the University of South Florida, Tampa, says the goal of his paper was to review oral immunotherapy and offer guidance to clinicians on the practice.

Before January 2020, the only way to manage food allergies was to avoid the offending foods altogether or to manage the acute allergic reactions that follow. With the US Food and Drug Administration’s (FDA) approval earlier this year of Palforzia®, oral immunotherapy got a boost. Oral immunotherapy has long been a promising and novel treatment for food allergies. Palforzia is a new medication aimed at reducing allergic reactions during accidental peanut exposure in children who have peanut allergies. When used with oral immunotherapy, it can reduce the risk of severe allergic reactions. Palforzia isn’t the only method for oral immunotherapy, though.

“With no therapies available other than 1 product for oral immunotherapy, some allergists are doing immunotherapy with non-approved products based on their experience,” Casale says. “This has provided opportunities for some patients to avail themselves of this treatment. However, the time commitment and potential adverse events during therapy need to be considered. Patients and parents must have the appropriate amount of time to devote to this therapy and training to treat potential adverse consequences of the therapy such as allergic reactions. Unfortunately, immunotherapy nor any treatment under study for food allergy has been shown to induce a cure. Thus, patients may have to be on this treatment indefinitely.”

It’s also important to note that when using Palforzia or other methods for oral immunotherapy, it’s key to consider the amount of protein content. Any products used for oral immunoptherapy should have the protein content and information clearly labeled, as well as cross contamination risks. This is particularly important for products that are not pharmaceutical grade or FDA approved, the report notes.

It’s also essential to note that oral immunotherapy is not the right fit for everyone.

“This treatment would be appropriate for select patients,” Casale says, adding that it’s important to consult with an allergist or immunologist to determine if a patient was a good candidate for this medication. Facilities that embark on oral immunotherapy must also be equipped to handle severe allergic reactions, and only families who are motivated and have a strong support system should be enrolled in this type of therapy.

Clinicians should also be prepared to expect anxiety—probably from parents and patients alike—when initiating oral immunotherapy, Casale adds. This anxiety isn’t a deal-breaker, though.

“Parents have a lot of anxiety about food allergy especially when their children are in environments that they cannot control like schools and parties. If the risk of having an allergic reaction to food and the anxiety surrounding that are great, then oral immunotherapy might be a suitable therapy,” Casale says. “However, this needs to be a joint decision between provider, patient, and parents. Oral immunotherapy is associated with allergic reactions. However, these reactions are expected and more effectively managed.”

The decision to start oral immunotherapy is not—and should not—be taken lightly, or by those who are not trained and qualified to do so, Casale warns.

“I would not recommend that either parents or pediatricians not trained in allergy do this on their own,” Casale says, adding that Palforzia is recommended for use only by allergists. “Because of the nuances involved in doing oral immunotherapy—including the choice of correct patients—the management of adverse reactions and the required on-call supervision, pediatricians may find this extremely difficult to do. In no way would I recommend this for patients on their own.”

Reference

1. Pepper A, Assa’ad A, Blaiss M, et al. Consensus report from the Food Allergy Research & Education (FARE) 2019 oral immunotherapy for food allergy summit. JACI. 2020;146(2):244-249. doi:10.1016/j.jaci.2020.05.027