Higher Maintenance Doses Linked to Lower Cedar Pollen IgE in Children on Immunotherapy

Children receiving subcutaneous immunotherapy for Japanese cedar pollen allergy showed heterogeneous changes in pollen-specific immunoglobulin E, with higher maintenance and annual cumulative doses associated with proportionally greater reductions in this laboratory marker, according to a retrospective cohort study published in Allergy, Asthma & Clinical Immunology. The study, a brief report on 58 children aged 5 to 15 years who received standardized Japanese cedar pollen subcutaneous immunotherapy for at least two years, examined how dosing parameters relate to changes in allergen-specific IgE, an immunologic biomarker rather than a validated measure of clinical benefit.

The researchers calculated the ratio of post-treatment to pre-treatment Japanese cedar pollen-specific IgE values, log10-transformed for analysis, and used Spearman rank correlation with Benjamini-Hochberg adjustment to test associations with maintenance dose, annual cumulative dose, injection interval, and treatment duration. At baseline, the median Japanese cedar pollen-specific IgE value was 94.7 UA/mL, and after immunotherapy it was 84.0 UA/mL. Although the medians were similar, the paired values differed significantly, with a P value of 0.013, and post-treatment values were equal to or higher than baseline in most children.

Within individual patients, the changes were far from uniform. The median post-treatment to pre-treatment ratio was 1.42, meaning that for the typical child in the cohort, pollen-specific IgE was measurably higher after treatment than before. Only 21 of the 58 children, or 36.2 percent, had a ratio below 1.0, indicating a decrease in this antibody. This heterogeneity underscores that group medians can mask widely divergent individual responses, a point the authors make explicit in reporting the distribution of ratios rather than a single summary change.

Against that background, the dose associations stood out. Maintenance dose showed a modest negative correlation with the IgE ratio, with a Spearman rho of −0.394 and an adjusted P value of 0.004. Annual cumulative dose behaved similarly, with rho of −0.405 and an adjusted P value of 0.004. In practical terms, children who received higher maintenance doses, or larger total doses over each year of treatment, tended to have lower post-treatment to pre-treatment IgE ratios. By contrast, no clear association was detected for injection interval, which had a rho of 0.084, or for treatment duration, with a rho of −0.008.

The optimal maintenance dose and injection interval for Japanese cedar pollen subcutaneous immunotherapy in children remain unclear, which is the gap the study set out to address.

Safety data from the maintenance phase were reassuring within the limits of the report. No systemic allergic reactions were documented during maintenance treatment. The authors nonetheless caution against overinterpreting the findings. The correlations they report are described as exploratory and hypothesis-generating, and the study design was retrospective, meaning treatment assignments and outcome measurements were analyzed from existing records rather than prospectively planned.

A central limitation is that Japanese cedar pollen-specific IgE is not a validated surrogate of clinical benefit. A falling IgE ratio does not necessarily translate into fewer symptoms, less medication use, or better quality of life. Standardized clinical outcomes were unavailable in this cohort, so the study cannot say whether children with lower ratios actually felt better during pollen season. The authors state that prospective studies incorporating symptom scores, medication use, quality-of-life measures, and safety outcomes are needed to determine the clinical relevance of the observed associations.

For clinicians and researchers, the report adds a specific, quantified observation to a sparsely mapped area: in this pediatric cohort, dosing intensity, not injection spacing or treatment length, tracked with the immunologic marker. Whether deliberately raising maintenance doses improves allergic rhinitis outcomes in children remains an open question that only prospective, clinically anchored trials can answer. Until then, the study’s modest negative correlations should be read as a signal for further research rather than a basis for changing practice.

Subject of Research: Associations between dosing parameters and Japanese cedar pollen-specific IgE changes in pediatric subcutaneous immunotherapy

Article Title: Maintenance dose and Japanese cedar pollen-specific immunoglobulin E changes during pediatric Japanese cedar pollen subcutaneous immunotherapy

Article References: Fujita, M., Matsumoto, Y., Takamasu, T., & Inuo, C. (2026). Maintenance dose and Japanese cedar pollen-specific immunoglobulin E changes during pediatric Japanese cedar pollen subcutaneous immunotherapy. Allergy, Asthma & Clinical Immunology. https://doi.org/10.1186/s13223-026-01064-8

Image Credits: AI Generated

DOI: 10.1186/s13223-026-01064-8

Keywords: Japanese cedar pollen, subcutaneous immunotherapy, allergen-specific IgE, pediatric allergy, maintenance dose, retrospective cohort, allergic rhinitis, immunologic biomarker, dose-response, Benjamini-Hochberg adjustment, Maintenance, dose