Research report: Baseline immune profiles are associated with positive outcomes in young children with a peanut allergy, enrolled in a randomised clinical trial for oral immunotherapy

Toddlers with peanut allergy respond very differently to oral immunotherapy, and a new randomised controlled trial analysis suggests their blood immune profiles before treatment may help explain why. In the Early Peanut Immunotherapy in Children (EPIC) trial, researchers assessed blood samples from 49 peanut-allergic children aged one to four years. Twenty-four children were randomised to receive peanut oral immunotherapy (OIT), while 25 followed the current recommended clinical practice of strict peanut avoidance for twelve months.

The clinical results were striking. Oral immunotherapy induced either partial or complete desensitisation in 91.3 percent of participants in the intervention group, compared with 20.8 percent in the avoidance group. Desensitisation was assessed using an end-of-treatment oral food challenge, and blood samples were collected at baseline, at a 12-week follow-up for the OIT group only, and at the end of treatment.

To understand what distinguished responders, the team used an established immune cell flow cytometry panel together with an FcεR1 expression panel, identifying thirty immune cell subsets in each sample. After twelve weeks of treatment, OIT-treated children showed an expansion of basophils, monocytes and dendritic cells compared with levels measured at recruitment. By the end of treatment, OIT had increased the abundance of CD4− T effector memory cells and mast cell progenitors.

Younger children with low levels of peanut-specific IgE were more likely to achieve complete desensitisation. Complete desensitisation was also associated with low levels of CD4+ memory regulatory T cells and CD4− central memory T cells measured at recruitment, whereas higher levels of basophils at baseline were associated with partial desensitisation.

Differences between partial and complete responders extended beyond cell counts. The researchers observed distinct patterns of dendritic cell activation and of expression of the IgE receptor, FcεR1, between the two outcome groups, indicating that the character of the allergic immune response at baseline tracks with how far treatment can take a child.

Peanut allergy affects around three percent of Australian infants, can cause life-threatening anaphylactic reactions and often persists throughout life. Oral immunotherapy is considered a promising route to desensitisation, but outcomes vary considerably between patients, which is precisely the gap this study set out to address by describing the immunological profiles associated with favourable results.

The authors caution that their findings are associative and drawn from a single trial in a small, young cohort. The immune signatures they identified suggest potential utility in monitoring treatment progress and, in the future, in identifying the children most likely to benefit from OIT before therapy begins. They do not, by themselves, establish that these immune markers cause better outcomes or that they should change clinical practice today.

The new immune data suggest that, with further validation, a simple baseline blood profile could eventually help predict which children fall into the successful majority.

Subject of Research: Immune cell profiles associated with oral immunotherapy outcomes in young children with peanut allergy

Article Title: Baseline immune profiles are associated with positive outcomes in young children with a peanut allergy, enrolled in a randomised clinical trial for oral immunotherapy

Article References: Coenen, I., Figliomeni, A., Parkin, K., de Asis, J., White, A. A., Miller, S., Metcalfe, J., Strickland, D. H., O’Sullivan, M., & Leffler, J. (2026). Baseline immune profiles are associated with positive outcomes in young children with a peanut allergy, enrolled in a randomised clinical trial for oral immunotherapy. Allergy, Asthma & Clinical Immunology. https://doi.org/10.1186/s13223-026-01061-x

Image Credits: AI Generated

DOI: 10.1186/s13223-026-01061-x

Keywords: peanut allergy, oral immunotherapy, desensitisation, immune profiling, flow cytometry, basophils, dendritic cells, regulatory T cells, IgE, randomised controlled trial, pediatric allergy, biomarkers