[DISCLAIMER: Oral Immunotherapy is always conducted under the direction and supervision of a medical doctor. It is an individualized plan. Please talk to your doctor if you’re interested in learning more about OIT. This is not an endorsement of OIT and is for informational purposes only.]
UPDATE: Palforzia was approved by the FDA in late January 2020 and is use today. If you choose to pursue OIT, discuss whether Palforzia or other OIT programs are best for you with your healthcare provider.
While the U.S. Food and Drug Administration considers whether to approve Aimmune’s Palforzia – possibly the first drug to be approved for peanut allergy, let’s get an overview of OIT.
Oral immunotherapy isn’t a new concept. In fact, it has been discussed in medical journals for over a century and used for decades to help patients desensitize to environmental and drug allergies as well as build a tolerance to venom. OIT has been studied in food allergy (mostly for peanut allergy) for the last 20 years and been in medical trials for just over 10 years.
Following a successful presentation to the U.S. FDA in September 2019, we stand on the cusp of seeing the first oral immunotherapy drug (Palforzia) approved. Until now, food allergic patients have had no other option but to avoid their allergen for the life of their allergy. FDA-approved drugs, like Palforzia, and other therapies would offer some patients progress, giving them much-needed treatment options to increase tolerance and protect them from life-threatening reactions for the very first time.
What is OIT?
Oral immunotherapy – or OIT – is a treatment option for some with food allergies that is managed and is strictly monitored by a patient’s allergist. [NOTE: OIT and desensitization should ONLY be done under medical supervision and with guidance from your personal doctor.]
Oral immunotherapy is a safeguard. It is a therapy intended to protect patients should they accidentally be exposed to their allergen. It can also bolster a patient and caregiver’s mental health by reducing anxiety and stress caused by the heavy burden of food allergy management and unexpected, potentially life-threatening reactions.
Immunotherapy (whether oral, epicutaneous, sublingual or otherwise) is a treatment option to help patients tolerate a higher level of allergenic protein and is NOT a cure for food allergies.
How does it work?
OIT is a form of desensitization – that is, the process of retraining a patient’s body to tolerate a larger amount of the allergen to which they are allergic without causing a reaction.
For example, if a patient is allergic to peanuts, a doctor would give a patient an amount of peanut protein (beginning with a tiny dose of 1/100th of a peanut or three milligrams). That dose is gradually increased until that patient can safely eat a level of protein that would otherwise cause a reaction. The goal of many OIT programs is to get the patient to tolerate at least 600 mg of peanut protein (or the equivalent of 2 peanuts), although these goals vary from practice to practice and patient to patient.
Is OIT only for those with a peanut allergy?
Although the FDA is currently only reviewing a drug aimed at peanut allergy, oral immunotherapy trials are available for those who suffer from other food allergies as well.
How effective is oral immunotherapy? Does it work?
Peanut, egg and milk OIT has been studied most closely and shown to desensitize 60-80% of participants. Studies related to peanut oral immunotherapy specifically have between 85-90% success rates. Other food allergens have not been studied as thoroughly and initial results show they may not be as effective at increasing a patient’s tolerance. These numbers are the result of oral challenges and not real-world accidental exposure.
Can anyone pursue oral immunotherapy?
If you’re interested in OIT, it’s best to speak with your doctor. The process of going through OIT can be demanding and does not fit every lifestyle. And, there are certain food allergy-related conditions (such as eosinophilic esophagitis – EOE – and others) that might make immunotherapy more difficult.
There are a few side effects that are possible while undergoing OIT. The most common issue patient’s experience is gastrointestinal (reflux, cramping and vomiting), followed by oral itching, hives, and wheezing. The risk for anaphylaxis is higher for those going through immunotherapy due to a patient’s regular exposure to their allergen. Patients also risk developing/inciting EOE – which often goes away when therapy discontinues.
The process of oral immunotherapy can be rigorous. It requires an oral challenge, frequent doctor’s visits, and a comfort with using an epinephrine auto-injector. Therapy also puts some restrictions on the life of patients as a precaution. For example, after dosing patients are required to rest to keep their body temperatures steady for 2 to 4 hours. And, daily monitoring is required.
Patients often need to take a daily or weekly maintenance dose indefinitely to keep up their tolerance.
Oral immunotherapy is a much-needed treatment options for those seeking some protection and relief from the demands of living with food allergies. Safeguarding patients against cross-contamination and accidental exposure is important for a patient’s physical as well as mental well-being. But OIT is not for everyone. If you’re interested, talk to your doctor about OIT and see if it’s a good fit for your lifestyle.
For more information, please read:
The Current State of Oral Immunotherapy from AAAAI