More than 60 percent of children with multiple food allergies who began eating their allergens after treatment with omalizumab were still doing so a year later. About the same number who completed multi-allergen oral immunotherapy were still eating their allergens.
Researchers concluded that omalizumab (the brand Xolair) and oral immunotherapy were similarly effective when it came to allergen introduction. Each enabled children with multiple food allergies to introduce foods into their diet and maintain consumption over the longer term.
Ultimately, the findings suggest families may have more than one path to reaching the same goal: regularly eating foods that once caused allergic reactions, says lead study author Dr. R. Sharon Chinthrajah. She’s a professor of pediatric food allergy, immunology and asthma at Stanford University.
“Omalizumab or multi-food oral immunotherapy are equally effective in getting patients to a place where they can introduce real foods into their diet to maintain desensitization,” Chinthrajah says.
In the study, dietary consumption meant eating at least 300 milligrams (mg) of an allergenic food. Some children were consuming substantially more, up to full serving sizes, of one or more of their allergens.
Real-World Test: Eating Food
The results are from Stage 3 of OUtMATCH, a large, double-blinded, placebo-controlled trial. An earlier stage helped lead the Food and Drug Administration to approve omalizumab in 2024 to protect against allergic reactions to small, accidental exposures to food allergens. At present, the injectable medication is only approved for this use.
The trial included children ages 1 to 17 who were allergic to peanuts and at least two of milk, eggs, wheat, walnuts, hazelnuts, and cashews. Stage 3 was designed to reflect real-world eating after treatment ended.
Children in this phase followed one of two treatment approaches. Some had 60 weeks of omalizumab, which was stopped when they began consuming their allergenic foods. Other children had 16 weeks of omalizumab followed by 52 weeks of multi-allergen oral immunotherapy. In OIT, children eat their allergen in gradually increasing amounts over months to build tolerance.
“In Stage 3, you stop omalizumab. You stop OIT. You are just eating food,” Chinthrajah says.
The 80 children in Stage 3 included 51 in the omalizumab group and 29 in the OIT group.
Patients were told to eat at least 300 mg of at least one, and up to three, of their allergens. Researchers gave them minimum and maximum daily amounts, based on how much they tolerated during food challenges.
Stage 3 was meant to mimic real-world eating, to “give patients some choice,” says Dr. B.J. Lanser. If children felt like eating more or less of a food on a given day they could, as long as they stayed within the daily limits, says the study co-author and pediatric food allergy program director with National Jewish Health. Consumption was recorded in food diaries through six months.
In both groups, some children were eating up to 6 grams of their allergens, about a serving size.
Xolair vs. OIT: Similar Results
After six months, 66 percent of children who had completed OIT were still eating their allergens. About 63 percent of those who had received omalizumab were. These differences were not statistically significant.
At one year, the study team evaluations found similar numbers: about 67 percent of children who had done OIT and 63 percent of children who had received omalizumab were still eating the foods.
Regardless of the approach, “you were equally successful in being able to introduce foods into your diet and keep it in your diet at three and six months,” Chinthrajah says. “They give us different treatment pathways to get to the same place.”
She notes that “once you stop omalizumab, it’s out of your system in two to three months. So the persistent effects are from starting the foods when you stopped omalizumab to keep the desensitization effect in play.”
They found no significant differences in dietary consumption rates at one year among the different foods.
For families, this could mean having a choice between approaches to desensitization and eventually incorporating foods into the diet. Some patients may choose omalizumab before food introduction, while others may pursue OIT without medication.
Factors for families to consider are the cost of Xolair versus OIT, whether the child is willing to do injections, or if they can adhere to OIT protocols. The latter include strict dosing schedules and rest periods after dosing.
“OUtMATCH in total is giving us different treatment pathways to get to real-world food introduction,” Chinthrajah says. “The journey to that point can come in different forms. It can be omalizumab alone. It can be omalizumab with multi-allergen OIT. Or it can be multi-allergen oral immunotherapy alone.”
Earlier OUtMATCH Stages
Earlier stages of OUtMatch found that Xolair can protect from reactions due to accidental exposures to small amounts of food allergens. Stage 1 showed that after four months of Xolair injections, 67 percent of patients receiving Xolair could tolerate at least 600 milligrams of peanut protein, or 2½ peanuts. About 66 percent could tolerate about 1,000 mg of milk (2 tablespoons). Other foods ranged from 67 percent for egg to 41 percent for cashew. (These patients were still taking Xolair at the time they underwent the food challenges).
Those findings helped omalizumab become the first FDA-approved medicine for reducing allergic reactions, including anaphylaxis, in adults and children ages one and older with more than one food allergy.
The medication is given by injection, every two to four weeks. The first few shots are given in a doctor’s office, but after that, it can be self-administered at home.
Stage 2 of OUtMATCH compared Xolair with multi-allergen OIT in building tolerance. In that phase, 117 children received Xolair for 16 weeks. At the 9-week mark, half of the children started OIT, while the other half began placebo OIT. At week 16, the children receiving OIT switched to placebo injections while those receiving placebo OIT continued Xolair injections for an additional 44 weeks.
In 2025, the research team reported on 60 children who had received six months of omalizumab, before halting the medication and introducing the foods into their diet. That study found nearly all participants started eating at least one of their allergens initially, while about two-thirds introduced all three foods.
However, after one year, both the number of foods eaten and the amounts declined. Eighty percent were still eating at least one allergen, while only 58 percent maintained all three.
Safety and Side Effects
In the current Stage 3 study, safety was similar for both groups. About 86 percent of participants treated with omalizumab only and 93 percent of those who had done OIT experienced at least one adverse event.
Two cases of anaphylaxis requiring epinephrine occurred in the OIT group after the transition to dietary consumption. One case of eosinophilic esophagitis occurred in the omalizumab group.
Chinthrajah presented the results at the 2026 American Academy of Asthma, Allergy and Immunology Annual Meeting in Philadelphia.
Xolair is an anti-IgE biologic, or antibody made in the lab. It works by blocking IgE antibodies, which are responsible for allergic reactions.
Related Reading:
Allergy Mom Video: My Son Starts on Xolair for Food Allergies
FDA Approves Xolair to Avert Severe Food Allergy Reactions
Xolair and Food Allergy FAQ: From Doses to Risks, Insurance, OIT
