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

Abstract The optimal maintenance dose and injection interval for Japanese cedar pollen (JCP) subcutaneous immunotherapy (SCIT) in children remain unclear. In a retrospective cohort of 58 children aged 5 to 15 years who received standardized JCP-SCIT for at least 2 years, we examined associations of maintenance dose, annual cumulative dose, injection interval, and treatment duration with the log10-transformed post-/pre-treatment JCP-specific IgE ratio, a laboratory immunologic biomarker, using Spearman rank correlation with Benjamini-Hochberg adjustment. At baseline and after SCIT, median JCP-specific IgE values were 94.7 and 84.0 UA/mL, respectively; nevertheless, the paired values differed significantly ( P = 0.013), with post-treatment values equal to or higher than baseline in most children. Within-patient changes were heterogeneous: the median post-/pre-treatment ratio was 1.42, and only 21 of 58 children (36.2%) had a ratio below 1.0. Maintenance dose (rho = − 0.394, adjusted P = 0.004) and annual cumulative dose (rho = − 0.405, adjusted P = 0.004) showed modest negative correlations with the ratio, whereas no clear association was detected for injection interval (rho = 0.084) or treatment duration (rho = − 0.008). No systemic allergic reactions were documented during maintenance. Exploratory, hypothesis-generating associations were observed between higher maintenance and annual cumulative doses and lower post-/pre-treatment JCP-specific IgE ratios during pediatric JCP-SCIT. Because JCP-specific IgE is not a validated surrogate of clinical benefit and standardized clinical outcomes were unavailable, prospective studies with symptom, medication, quality-of-life, and safety outcomes are needed to determine the clinical relevance of these associations.