Exploratory pilot trial of a multicomponent immunonutritional supplement in children with allergic asthma and rhinitis: The INAPRA study

Background Allergic asthma and allergic rhinitis (AR) are among the most frequent chronic conditions in the pediatric age. They frequently coexist in children and are sustained by type 2– driven airway inflammation and impaired epithelial–immune interactions. Immunonutritional and postbiotic strategies have been proposed as adjunctive therapeutic approaches for these diseases. Objective To explore the clinical and immunomodulatory potential of a multicomponent immunonutritional supplement containing postbiotics in children with concomitant allergic asthma and AR. Methods The ImmuneNutrition Against Pediatric Respiratory Allergies (INAPRA) study was a multicenter, randomized, double-blind, placebo-controlled exploratory pilot trial. Forty children aged 5–12 years with asthma and AR sensitized to Dermatophagoides pteronyssinus were randomized (1:1) to receive a daily multicomponent supplement (sodium butyrate, heat-inactivated L. rhamnosus GG, fructooligosaccharides, vitamin D3, docosahexaenoic acid, quercetin, and Perilla frutescens extract) or placebo for 6 months. Co-primary outcomes were changes in respiratory symptom control assessed by Childhood Asthma Control Test (c-ACT), CARATkids, and Total Nasal Symptom Score (TNSS). Secondary outcomes included cytokine production, regulatory T-cell rate and tolerogenic gene expression (gfb1, Ptgs2, Csf2, and Ifna2) in peripheral blood mononuclear cells (PBMCs). Immunological assays were performed in vitro on PBMCs collected before intervention. Results Baseline clinical characteristics were comparable between groups. In baseline-adjusted analyses, children receiving the study product showed more favorable 6-month outcomes than those receiving placebo across all three prespecified symptom-control measures. The adjusted between-group difference was 4.625 points (95% CI 3.705 to 5.545; p < 0.001) for c-ACT and − 3.960 points (95% CI −4.890 to −3.030; p < 0.001) for TNSS. For CARATkids, a significant treatment-by-baseline interaction was detected; at the mean baseline score, the adjusted conditional between-group difference was −7.019 points (95% CI −8.143 to −5.895; p < 0.001). The use of rescue medications was higher in the placebo group. No adverse events related or unrelated to the study product were reported, and adherence exceeded 90%. In in vitro experiments, co-incubation with the study product attenuated allergen-induced Th2 cytokine secretion (IL-4, IL-5, IL-13), increased IL-10 production, enhanced CD4 + CD25 + FoxP3 + regulatory T-cell rate, and upregulated Tgfb1, Ptgs2, Csf2, and Ifna2 expression. Conclusions In this exploratory pilot RCT, six-month supplementation with a multicomponent immunonutritional formulation was associated with improvement of allergic asthma and rhinitis control in children. The clinical improvement paralleled with beneficial modulatory actions in immune cells., Trial Registration ClinicalTrials.gov Identifier NCT07308288