Short-Term Xolair Helps Food Allergy Patients Fast-Track OIT

A prospective study published in the Annals of Allergy, Asthma & Immunology found that a short course of omalizumab (Xolair) pretreatment enabled most participants with multiple food allergies to bypass traditional incremental up-dosing and initiate oral immunotherapy (OIT) directly at target maintenance doses. Led by Colleen M Shannon, MD, MPH, and colleagues at the Children’s Hospital of Philadelphia (CHOP), the real-world prospective cohort evaluated whether pairing anti-IgE biologic therapy with OIT could streamline treatment protocols while maintaining an acceptable safety profile.

Traditional OIT protocols require multi-step initial dose escalation and frequent in-office visits over several months to gradually increase food allergen doses. For children and young adults managing multiple food allergies, this stepwise escalation can place a significant burden on families and clinical teams. Pretreatment with omalizumab—an FDA-approved monoclonal antibody targeting IgE—can raise the threshold for allergic reactions, potentially allowing patients to begin OIT at higher doses and reduce the amount of incremental up-dosing required.

The CHOP study enrolled 100 children and young adults with multiple food allergies who initiated omalizumab-facilitated OIT between July 2024 and October 2025. Participants underwent a minimum of eight weeks of omalizumab pretreatment before facing a two-dose initiation challenge for each target food allergen. Patients who successfully tolerated the challenge immediately began daily home maintenance dosing for most foods in their regimen, while any remaining foods underwent abbreviated up-dosing schedules.

The study’s primary outcome—tolerance of the initiation challenge without dose-limiting symptoms—was achieved in 181 of 193 initiation challenges, or 94%. Participants received omalizumab for a median of 12 weeks before their initiation challenges (9.5–15.8 weeks). Overall, 97% of participants successfully initiated daily dosing for at least one food, while 84% started directly at target maintenance doses across all foods in their regimen.

Over a median follow-up period of 27.6 weeks, the protocol maintained what investigators characterized as an acceptable safety profile. Mild-to-moderate adverse events were reported by approximately 40% of participants, with abdominal pain (23%) and oral itch (13%) the most common symptoms. Treatment discontinuation due to adverse events was rare, occurring in only two patients, while the median overall omalizumab treatment duration was 26.3 weeks among those meeting criteria to discontinue the biologic. As the study authors concluded, “This approach may reduce treatment burden while maintaining an acceptable safety profile.”

The findings arrive alongside data from Stage 2 of the randomized OUTMATCH trial, which compared continued omalizumab treatment with multiallergen oral immunotherapy (MOIT) after participants had initially received omalizumab. In that trial, continued omalizumab achieved higher intention-to-treat success than MOIT (36% vs 19%), an outcome influenced substantially by high dropout rates in the MOIT group (49% vs 12%). MOIT participants also experienced higher rates of serious adverse events (31% vs 0%), epinephrine-treated reactions (37% vs 7%), and anaphylaxis (27% vs 2%), highlighting the challenge of OIT tolerability.

Reflecting on the trade-offs between biologic monotherapy and oral immunotherapy, Robert A Wood, MD, professor of pediatrics at Johns Hopkins University School of Medicine, noted: “Both treatments can be effective, and both will provide protection from small exposures and even the ability to start eating the food directly.” However, Dr Wood emphasized that “the biggest difference we found was the side effects from oral immunotherapy were such a far larger group of patients really couldn’t tolerate the therapy.”

Together, the findings illustrate two potential roles for omalizumab in food allergy treatment: as ongoing monotherapy to increase protection against accidental exposures, and as a temporary adjunct that may help selected patients reach OIT maintenance doses while avoiding much of the traditional incremental up-dosing process. Longer-term studies will be needed to determine how well this accelerated OIT approach performs after omalizumab is discontinued.