Omalizumab Outperformed MOIT in Multifood Allergy Trial

Key Takeaways

• Patients with peanut allergy plus at least two additional food allergies in OUTMATCH stage 2 had higher overall treatment success with continued omalizumab than with omalizumab-facilitated multiallergen oral immunotherapy.
• Completion was more common with omalizumab than with multiallergen oral immunotherapy, at 88% versus 51%, and adverse events accounted for more discontinuations in the oral immunotherapy arm.
• Among participants who completed treatment, efficacy was reported as similar, indicating that the intention-to-treat difference was tied largely to tolerability and retention.
• Serious adverse events were more frequent with multiallergen oral immunotherapy, including anaphylaxis and epinephrine-treated reactions; the MOIT arm also had more adverse events leading to treatment discontinuation and three cases of eosinophilic esophagitis, while duration-, dose-, and age-related signals remained exploratory.

Sustaining protection across several trigger foods remains difficult in multi-food allergy because treatment burden and tolerability matter alongside desensitization. Omalizumab gained US Food and Drug Administration (FDA) approval in 2024 to reduce allergic reactions, including anaphylaxis, after accidental exposure to one or more foods, but direct head-to-head evidence against oral immunotherapy had been limited even as nonapproved oral immunotherapy products continued to be used in practice. That treatment-choice question led to stage 2 of OUTMATCH.

Stage 2 of the OUTMATCH stage 2 randomized trial in JAMA Pediatrics was a multicenter, double-blind, placebo-controlled study in participants allergic to peanut and at least two additional specified foods, including milk, egg, wheat, cashew, hazelnut, or walnut. The enrolled and randomized cohort included 117 participants aged 1 to 29 years. All participants received 16 weeks of open-label omalizumab, multiallergen oral immunotherapy (MOIT) or placebo-MOIT was added at week 8, and blinded injections continued for 44 weeks after week 16, with escalation to a maintenance dose of 250-1000 mg per food over 24 weeks. Oral food challenges (OFCs) after 52 weeks measured cumulative tolerated dose (CTD), with the primary endpoint defined as 4044 mg or greater for all three participant-specific foods, and withdrawal before the final challenge counted as failure.

Continued omalizumab achieved treatment success in 36% of participants versus 19% with omalizumab-facilitated MOIT in the intention-to-treat analysis, and the summary described the difference as significant. Completion also favored omalizumab, at 88% versus 51%. Several secondary tolerance outcomes also favored omalizumab, particularly for higher doses of peanut, milk, and egg, while no efficacy difference was seen in the per-protocol analysis.

The higher overall success with omalizumab was reported as being driven mainly by fewer adverse events and fewer treatment discontinuations rather than greater efficacy among completers. The MOIT arm had more safety problems, including more serious adverse events such as anaphylaxis and epinephrine-treated reactions, more adverse events leading to treatment discontinuation, and three cases of eosinophilic esophagitis. The findings may not fully generalize because the trial enrolled a highly food-reactive population and used an intensive, protocol-driven MOIT regimen. Longer omalizumab exposure, higher MOIT maintenance dosing, younger age, and omalizumab use in both stages remained exploratory signals, and high baseline peanut immunoglobulin E (IgE) predicted discontinuation in the MOIT group.

In this randomized comparison, continued omalizumab produced higher overall treatment success than omalizumab-facilitated MOIT in stage 2 of OUTMATCH, while both approaches were described as viable options with distinct risk-benefit profiles. Further study, including cost-benefit analysis, was also called for.

Clinician Questions

Which patients were included in OUTMATCH stage 2 of omalizumab versus multiallergen oral immunotherapy?

The stage 2 design included participants allergic to peanut and at least two additional specified foods and allowed ages 1 to 55 years, but the enrolled and randomized cohort comprised 117 participants aged 1 to 29 years. Eligibility also required weight and immunoglobulin E (IgE) levels compatible with omalizumab dosing, along with prespecified OFC thresholds, and key exclusions included poorly controlled asthma, a history of severe anaphylaxis, eosinophilic gastrointestinal disease, and recent immunomodulatory therapy. The investigators characterized the cohort as highly food-reactive, which limits how broadly the findings extend.

How was treatment success defined in the OUTMATCH comparison of omalizumab and MOIT?

In stage 2, treatment success meant reaching a cumulative tolerated dose of 4044 mg or greater for all three participant-specific foods at the 52-week OFC. Withdrawal before the final food challenge counted as failure, so the endpoint captured both the ability to raise tolerance thresholds and whether participants remained on treatment long enough to be tested.

Why did omalizumab show higher overall success than omalizumab-facilitated MOIT in OUTMATCH stage 2?

According to the investigators, the higher overall success with continued omalizumab was reported to reflect fewer adverse events and fewer treatment discontinuations in the omalizumab group. They also reported similar efficacy in the per-protocol analysis among participants who completed treatment, which framed the intention-to-treat difference as a retention and tolerability signal rather than a clear difference in efficacy among completers.