Peanut IgE Stronger Predictor of Remission Than Age After Oral Immunotherapy

Age has not been identified as an independent predictor of remission of food allergies after oral immunotherapy (OIT), new findings suggest, with additional research being deemed necessary ahead of the widespread implementation of early intervention.1

These data were the conclusion of a recent analysis authored in part by Sarah E. Ashley, PhD, of the Murdoch Children's Research Institute in Australia. Ashley et al. highlighted that the desired result of OIT is remission, noting that early initiation of immunotherapy among infants and toddlers has largely been lauded as a useful means of encouraging remission.

Given the need to clarify whether age is an independent predictor of patients’ allergy remission, the investigators assessed interrelationships between baseline age and peanut-specific IgE (sIgE) titres as potential predictors of clinical outcome after OIT treatment. They specifically looked at participants in the PPOIT-003 randomized study.2

“It is critical to assess the reproducibility and generalizability of predictors for remission via external validation in independent patient cohorts,” Ashley and colleagues wrote. “Such external validation represents a key step for clinical implementation of accurate prediction models and to prevent wasted research efforts.”1

Study Design Details

The research team highlighted several key points about the PPOIT-003 multi-center, randomized controlled study during which children in the age range of 1-10 years were assessed during treatment with Probiotic and Peanut Oral Immunotherapy (PPOIT) and compared to those on peanut OIT alone or those given a placebo.

The team’s recruitment of participants was conducted across 3 different sites located in Adelaide, Melbourne, and Perth. The children involved in the study had challenge-confirmed peanut allergies per the requirements for inclusion.

They were randomized 2:2:1, with 83 individuals in the OIT arm, 79 in the PPOIT arm, and 39 in the placebo arm. The investigators stratified subjects into 2 age-related categories: those aged 1–5 years and those aged 6–10 years. They also stratified them based on a skin prick test (SPT) (≤ 10 mm and > 10 mm).

The team assessed outcomes among subjects after 18 months of treatment, utilizing double-blind, placebo-controlled food challenges. Those able to successfully finish the challenges at the conclusion of the treatment period (T1) and again following an 8-week-long peanut avoidance period (T2) were labeled as having sustained remission.

Subjects who succeeded in the first period but failed in the second stage were labled by the investigative team as patients who were desensitized without remission (DWR), and those who failed at T1 were considered by the team to have persistent peanut allergies.

The investigators assessed peanut-specific IgE, or sIgE, as well as the peanut component Ara h 2 sIgE using plasma samples which they gathered at the study’s baseline, at T1, and at T2. They assessed both peanut sIgE levels and age at the participants’ entry to the study as predictive variables of patients’ allergy remission.

In the study, remission was notably achieved by 46% of those in the PPOIT cohort, 51%of the OIT cohort, and only 5% of the placebo cohort.

Findings on Age Versus sIgE

The investigators’ logistic regression results demonstrated that higher peanut sIgE levels among the study’s subjects had a strong link with reduced likelihood of allergy remission, regardless of their recorded age.

Such a link was shown by the research team to be consistent in models accounting for age, with an unadjusted odds ratio (OR) of 0.10 (95% CI: 0.05–0.21, P < .001) and an adjusted OR of 0.10 (95% CI: 0.05–0.22, P < .001). The team emphasized the lack of an independent association between age and remission after adjusting for baseline peanut sIgE levels (OR 0.94, 95% CI: 0.79–1.12, P = .5).

“In summary, our findings showed that baseline peanut sIgE is a stronger predictor of remission following peanut OIT than age at treatment commencement,” they wrote. “This simple test can be used to inform clinical decision making regarding the commencement of peanut OIT in children. Future research performing meta-analysis of all studies that assessed for remission as a clinical endpoint could be used to further explore age as a predictor of outcome, and relevant interactions between age and baseline sIgE.”1

References

1. Ashley, S.E., Lloyd, M., Loke, P., Orsini, F., Lozinsky, A.C., O'Sullivan, M.D., Quinn, P., Gold, M. and Tang, M.L.K. (2025), Allergen Specific IgE is a Stronger Predictor of Remission Following Peanut Oral Immunotherapy Than Age in Children Aged 1–10 Years. Allergy. https://doi.org/10.1111/all.16451.
2. P. Loke, F. Orsini, A. C. Lozinsky, et al., “Probiotic Peanut Oral Immunotherapy Versus Oral Immunotherapy and Placebo in Children With Peanut Allergy in Australia (PPOIT-003): A Multicentre, Randomised, Phase 2b Trial,” Lancet Child Adolesc Health 6, no. 3 (2022): 171–184.