This study aims to evaluate the efficacy and safety of multi-food oral immunotherapy (multi-OIT) using peanut and tree nuts proteins in children with confirmed food allergy to at least two allergens. Participants will be randomized in a 2:1 ratio to receive either multi-OIT or standard management consisting of an elimination diet. The primary objective is to evaluate immunotherapy efficacy defined as achieving tolerance to a cumulative dose of 4444 mg of protein during an oral food challenge (OFC-2) for at least one allergen that elicited a reaction during baseline challenge (OFC-1), compared with the control group. Secondary outcomes include the proportion of participants tolerating multiple allergens at the target cumulative dose; the incidence, type, and severity of adverse events classified according to the World Allergy Organization (WAO) grading system; changes in immunological parameters, including allergen-specific IgE and IgG4 levels; changes in skin prick test responses; changes in the quality of life of patients and their families.
Age 1-12 years;
Confirmed allergy to at least two allergens included in the protocol, i.e., peanut and/or tree nuts: cashew, walnut, hazelnut, and almond;
Positive skin prick test (SPT) (wheal diameter ≥ 3 mm) and/or specific IgE (sIgE) level > 0.35 kUA/L for at least two of the analyzed allergens;
Positive OFC-1 (oral food challenge) of grade I-IV according to the WAO classification for at least two allergens, with a positive reaction occurring after administration of a dose ≥ 3 mg and ≤ 3000 mg of allergen protein;
Allergic reaction at the lowest challenge dose of 1 mg of allergen protein for any allergen, or no allergic reaction after administration of the maximum dose of 3000 mg of allergen protein for at least four of the analyzed allergens;
History of anaphylaxis with a grade V reaction according to the WAO classification, either during an oral food challenge or in the patient's medical history;
Severe asthma;
Poorly controlled asthma according to GINA 2025 (lack of symptom control and/or ≥2 exacerbations requiring systemic glucocorticoids or ≥1 exacerbation requiring hospitalization within the last 12 months), or in children able to perform spirometry: FEV1 < -1.64 Z-score and/or FEV1/FVC < -1.64 Z-score;