Avoid the allergen. For decades, that was the only advice for people with life threatening food allergies. While that is still true, the food allergy community is cautiously, but excitedly, watching research unfold that could help patients tolerate more of the allergen that might otherwise have serious or deadly consequences.
While that is still true, the food allergy community is cautiously, but excitedly, watching research unfold that could help patients tolerate more of the allergen that might otherwise lead to a trip to the emergency department (ED), a stay in an intensive care unit, or worse, becoming a fatal statistic.
To understand why, look no further than the period between Halloween and New Year’s Eve, when there’s a food-laden event seemingly every week, whether at work or school. If you’re only allergic to the ubiquitous peanut, the food may be easy enough to avoid, said Robert Wood, MD, the director of pediatric allergy and immunology at Johns Hopkins in Baltimore, Maryland.
But if you are allergic to multiple foods, like the majority of his patients, it becomes more difficult, and that is where biologic treatments like omalizaub (Xolair) and dupliximaub (Dupiment) come in. Both are being studied in combination with oral immunotherapy (OIT).
Last August, omalizaub was designated as a breakthrough therapy designation by the FDA as a possible food allergy treatment in conjunction with OIT, on the basis of 7 clinical trials looking at omalizaub against peanut, milk, egg, and other foods.
Dupliximaub, which won FDA clearance last month to treat moderate to severe asthma, is in phase 2 trials for food allergy.
Omalizumab is a humanized monoclonal antibody against immunoglobulin E (IgE), said Wood, who has been studying the possibilities of omalizumab for years. Omalizumab is already approved for asthma and chronic idiopathic urticaria (CIU), and is given by injections every 2 or 4 weeks, and costs about $ 2000 a dose.
The idea behind it is that it can both speed up the OIT process, reduce the side effects associated with OIT, and increase the threshold at which someone can eat the food that used to make them sick.
Why go to all that trouble? The main reason is that food allergy is incurable; the only treatment in case of a severe allergic reaction is epinephrine, a product that is currently in shortage by some manufacturers and the price of which has drawn scrutiny the past few years.
The cost of food allergy is not just the epinephrine or costs of possible ED visits. Patients with multiple allergies have to buy special foods and may lose time from work or school for medical appointments. One 2013 report said the direct and indirect costs of food allergy was estimated to cost $ 24.8 billion annually. The National Academies in 2017 said it appears by all accounts that the prevalence of food allergy is increasing, but also called for additional research in order to develop more accurate numbers.
That’s why some people, primarily parents of children with severe, multiple food allergies, are turning to OIT.
For Stacey Sturner, OIT has given her son, now 7, the ability to eat any quantity of peanut, after he successfully passed a 24-peanut challenge in August of 2017. That is on the condition that he continues to eat 8 peanuts a day. The entire process took about 6 months.
“Treatments, such as OIT, will soon become a routine part of food allergy care,” predicted Sturner, who runs a Facebook group for parents and others pursuing or considering treatment for food allergy.
OIT involves mixing in an allergenic food into something that the patient would tolerate, like applesauce or a liquid, and increasing the dose in gradually increasing amounts. Depending on the allergist, protocols can vary. That’s because neither of the 2 main medical associations for allergists – the American Academy of Allergy Asthma and Immunology, or the American College of Allergy, Asthma and Immunology, have officially endorsed OIT or come up with a standardized protocol for it.
Allergy guidelines as of right now “say that immunotherapy such as OIT is promising but is not quite ready for implementation in clinical practice,” said Wood. “There are allergists who are doing this. Allergen avoidance is the only way to avoid a reaction but this is easier said than done.”
While one estimate put the number of allergists performing OIT in private clinical practice in the dozens, what will change when and if omalizumab is approved is that it would probably be used in conjunction with standardized, commercial peanut OIT products currently in development as well.
If biologics for food allergies do come to market – a process Wood said is still at least 2 years away, at least in the case of omalizaub—the process would be simpler for both the clinician and the patient.
“If this really did work, the advantage this would have over other things being studied would be something that’s really very simple to use,” said Wood. “If you’re doing oral immunotherapy, you have a very complicated regimen of building a dose up, and seeing the patients regularly dealing with frequent reactions to the treatment. But with the omalizumab you’re going to get a shot every two weeks or every four weeks with a low adverse reaction rate. It would be a simpler approach.”
OIT involves mixing in an allergenic food into something that the patient would tolerate, like applesauce or a liquid, and increasing the dose in gradually increasing amounts. Depending on the allergist, protocols can vary, but in general there are 3 phases to OIT: an initial escalation phase, followed by a dose build-up phase and a maintenance phase.
Desensitization is defined as a temporary increase in the threshold for reactivity, and the person with allergies must keep eating their allergen in order to keep reactions at bay.