For adults and children with food allergies—and the parents of those children—accidental exposure to an allergen is a constant threat. Even when you read labels, ask about ingredients and do your best to stay safe, a tiny amount of the problem food can cause a severe allergic reaction.
Now, food allergy sufferers may find new relief thanks to a not-so-new drug. Omalizumab, long used for allergic asthma, was approved by the Food and Drug Administration for reducing allergic reactions to food. This development has the potential to make the threat of accidental exposure less frightening.
UNC Health allergist Edwin Kim, MD, answers common questions.
How does omalizumab work to treat food allergies?
When you eat a food you’re allergic to, immunoglobulin E (IgE) antibodies in the blood trigger a chemical response in the immune system by releasing histamine, which causes allergic symptoms. For the 1 in 10 adults and 1 in 13 children in the United States who have food allergies, these reactions can range from uncomfortable to life-threatening.
Omalizumab, which is delivered by injection, works by binding to IgE antibodies and reducing their ability to respond, which increases the amount of food it takes to cause a reaction. It is not approved for emergency treatment of allergic reactions, so don’t stop carrying an epinephrine auto-injector (EpiPen).
Taking omalizumab doesn’t mean you can let your guard down.
“It’s not a cure, so you have to continue to practice avoidance,” Dr. Kim says. “It provides a buffer of protection by reducing the allergic antibodies that respond to food exposure, so if you accidentally eat a small amount of the food, it helps to prevent reactions or decrease the severity if a reaction still occurs.”
What does the research show about omalizumab and food allergies?
Omalizumab, known by the brand name Xolair, was first approved by the FDA in 2003 for people with allergic asthma, and since then it has been approved for the treatment of chronic hives and sinus disease.
UNC was one of 10 sites involved in the OUtMATCH clinical trial, which demonstrated that a 16-to-20-week course of omalizumab, with participants receiving an injection every two to four weeks, increased the amount of peanut, tree nuts, egg, milk and wheat that children with multiple food allergies could consume without a moderate or severe reaction, compared with participants who received a placebo.
After treatment, 67 percent of participants were able to consume a single dose of peanut protein (approximately 2 ½ peanuts) without a reaction, while less than 7 percent of participants who received the placebo could. For egg, 67 percent of participants treated with omalizumab were able tolerate a single dose of egg protein without a reaction; none of the participants treated with placebo could. For milk, 66 percent of participants who receive omalizumab were able to tolerate milk protein without symptoms, compared with 10 percent who received a placebo.
“It’s important to keep in mind that omalizumab does not allow you to fully introduce the foods back into the diet,” Dr. Kim says. “You don’t change your avoidance behaviors around the food. But mistakes happen; maybe something isn’t labeled correctly. This will help if there’s an accidental ingestion.”
This ability to target multiple food allergies at once distinguishes omalizumab from other food allergy treatments, such as oral or sublingual immunotherapy, which involves small exposures to a single allergen to train the immune system not to react. That’s important because 40 percent of children with food allergies are allergic to more than one food.
Are there side effects or safety concerns with omalizumab?
The OUtMATCH trial evaluated the safety of omalizumab in children as young as 1; there were no serious adverse reactions.
“Because this drug has been available for 20 years for allergic asthma, we have lots of data that it’s very safe,” Dr. Kim says. “Allergists around the country have been using omalizumab on a regular basis, so they’re comfortable with how it’s given.”
Dr. Kim says the most common side effect is redness or pain at the injection site.
“There is a small risk of anaphylaxis (a life-threatening allergic reaction), so the first three injections are done in the office,” Dr. Kim says. After your doctor has monitored your response, you will be cleared to perform the injections at home.
While omalizumab affects antibodies in the immune system, Dr. Kim says the drug doesn’t impair other parts of your immune system, meaning you’re not at higher risk for viral infections like the cold or flu.
Who is a good candidate for omalizumab for food allergies?
Omalizumab can be prescribed to patients as young as 1 year old with one or multiple food allergies. Because omalizumab will only be effective at reducing responses for IgE-mediated allergies, it’s important to work with an allergist to confirm that symptoms are caused by an allergy rather than a food intolerance, which is a digestive system issue.
Dr. Kim says that people considering omalizumab should understand they’re making a commitment to an injection every two to four weeks while also practicing food avoidance.
“You are only protected for as long as you take the medication, so you have to be willing and able to do regular injections,” he says.
Omalizumab is covered by many insurances, but the amount of coverage varies by plan, and cost may be a factor for some when deciding to pursue an ongoing treatment, he adds.
“People may benefit while they’re in a transition,” Dr. Kim says. “If you have a kid in kindergarten or a teenager going off to college, omalizumab could provide an extra layer of protection as they leave the safety of home and go into a new environment.”
Dr. Kim says the treatment can also benefit people who live in areas without doctors or clinics that specifically treat food allergies.
“In the past, treatments have usually been limited to food allergy centers, but omalizumab is something that every allergist offers,” he says. “This opens up food allergy treatment to so many more people than before.”
Concerned about food allergies? Talk to your doctor or find one near you.