Currently, there is no cure for food allergy, though there are newly emerging therapies that show promise. The best studied treatments involve immunotherapy or desensitization to a food allergen using different methods of delivery.
Food allergen immunotherapy
There are three major forms of food allergen immunotherapy:
- Oral immunotherapy: the allergen is eaten
- Sublingual immunotherapy: the allergen is placed under the tongue
- Epicutaneous immunotherapy: an allergen patch is applied to the skin
With oral immunotherapy (OIT), small amounts of a food allergen are given by mouth in gradually increasing doses until the patient is able to eat a certain amount of the food allergen without a reaction so long as they are on this treatment. Currently, OIT is not a mainstream practice in Canada and it is not covered by provincial health plans. It is mostly done in research settings and in some allergists’ practices.
With sublingual immunotherapy (SLIT), small amounts of a food allergen are placed under the tongue and then swallowed or spit out. As with OIT, SLIT protocols include dose escalation and maintenance phases although the doses are typically smaller than those in OIT. SLIT is mostly done in research settings.
In epicutaneous immunotherapy (EPIT), a patch containing a food allergen is applied to the skin. Unlike OIT and SLIT, there’s a set amount of food allergen in the patch and it’s worn for an increasing number of hours per day. Once it’s worn for 24 hours per day, the patch is replaced daily. EPIT is mostly done in research settings.
While OIT, SLIT and EPIT provide hope, they are a potential treatment for some patients with food allergy, but not all. The information about such emerging therapies can change. As always, speak with your doctor if you have any questions or concerns.
- An oral food challenge (OFC) is often done at the start of a treatment to confirm a patient’s food allergy and determine what amount of allergen they react to. An OFC may also be conducted during the course of a treatment to see how much more the patient can eat without having an allergic reaction.
- Learn more about OFC on our diagnosis page.
Desensitization, tolerance and sustained unresponsiveness
Food allergen immunotherapy can potentially result in two outcomes: desensitization and tolerance. With desensitization, a patient can eat more of their food allergen without having a reaction, as long as they are taking daily doses of that food. When tolerance is achieved, a patient can stop eating that particular food for some time and then resume eating it, without having a reaction.
The term “sustained unresponsiveness” has been introduced to describe the ability of a patient to pass an OFC after stopping OIT and successfully introduce a previously allergenic food into their diet, as desired.
Vickery et al, JACI, 2014 https://www.jacionline.org/article/S0091-6749(13)01750-8/pdf
Clinical trials are underway for the following:
- Aimmune Therapeutics, Inc. has developed AR101, a biologic drug for peanut OIT. The drug comes in capsules filled with a specific amount of peanut flour. The capsules are opened and mixed into food that is eaten daily. Aimmune is planning to extend its protocol known as CODIT (characterized oral desensitization immunotherapy) to treat milk and walnut allergies.
- Viaskin® Peanut
- DBV Technologies has developed a patch containing protein powder for peanut EPIT. The “peanut patch” is applied daily to a patient’s back and when the powder combines with sweat, it dissolves into the skin. There are also plans for milk and egg patches.
- Omalizumab, known by the brand Xolair®
- Genentech’s Xolair, an injectable treatment, is used to treat asthma and chronic hives without a known cause. Studies in process are looking at Xolair as a solo therapy or in combination with OIT for treating food allergies.
OIT and other research studies are registered on clinicaltrials.gov.