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I have a toddler with severe food allergies. Is Xolair as life-changing as it seems?
—Skeptical and hopeful
I have written before about preventing allergies in kids by early introduction of allergens. But even with early introduction, some kids will develop allergies, and some will be severe. In principle, people can be allergic to almost anything, but most food allergies in kids are caused by just a few things: peanuts, tree nuts, eggs, milk, soy.
Until recently, the one approved treatment for severe peanut allergies was a medication called Palforzia, which was part of an approach called oral immunotherapy (OIT). It works by exposing children to small but increasing amounts of the allergen to develop a tolerance. However, Palforzia will be voluntarily discontinued on July 31, 2026. The good news is that the discontinuation is not related to product safety, quality, or efficacy — the main issue was low demand, in part because it is possible for individual doctors to do a similar OIT procedure without this medication. Families affected by this change should consult their child’s doctor to discuss next steps.
Xolair is exciting because it promises a second possible treatment avenue, and one that isn’t limited to peanuts. This medication — generic name omalizumab — is already approved and in use to treat some types of asthma and other conditions. It’s a monoclonal antibody that works by decreasing the reaction to allergens.
A trial was published in 2024 in the New England Journal of Medicine that analyzed data from 177 children with severe food allergies. Inclusion in the trial required an allergy to peanuts plus at least two other foods from a list (eggs, milk, cashews, wheat, hazelnuts, or walnuts). Put differently, this was a very allergic population.
Two-thirds of the group received the treatment and one-third got a placebo. At the end of the study, the researchers evaluated whether the treatment group was less reactive to an allergen challenge. As is common in this type of study, it specified a particular amount of the allergen — someone “passed” if they were able to tolerate that amount, and not otherwise. The primary endpoint was based on tolerance of peanuts.
The medication was very effective. Two-thirds of the treatment group were able to tolerate the specified endpoint, versus just 7% of the placebo group. This is a large treatment effect, and the authors found similarly large impacts on other allergens.
This is, broadly, great news. Not only does it provide a possible treatment for kids over 1 with severe food allergies, but it also offers hope for further development of this type of treatment. These options are only likely to get better over time. This option may be more palatable to some parents than the existing oral immunotherapy, since severe reactions to the treatment were much less common.
A few caveats, though. First, although two-thirds of the treatment group responded, one-third did not. This treatment, at least at these doses, didn’t work for everyone. Second, even successful treatment doesn’t mean people can go out and eat a lot of the allergen. This is really a way to make accidental exposures less dangerous. Finally, this treatment is an injection given every two to four weeks, indefinitely. This may make it less palatable to children.
Since the publication of this trial, there has been further data that suggests that there is value in combining this medication with OIT. That is: under the supervision of a doctor, families use OIT along with Xolair. This may be beneficial in developing a longer tolerance, with fewer side effects during treatment.
Overall, the landscape of treatment for severe allergies right now is completely different than in was even a decade ago. Along with our better knowledge of how to prevent allergies in the first place, with early exposure, we are headed for a much better place. Huge win for science, and for families.
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Palforzia is being removed from the market because of lack of uptake. That’s because the clinical trials that proved it worked opened the door for many more providers to feel comfortable offering OIT (oral immunotherapy). It would be great if you could write a follow up on the emerging research on OIT as many people are not yet aware of it as an option and it can be even more life changing than Xolair.
Thank you, Meg! We’ve updated our piece to reflect the Palforzia update.