Immunological Response After Shrimp Oral Immunotherapy Treatment
Phase: NA
Conditions: Allergy to Shrimp, Immunotherapy
Sponsor: Mahidol University

Study Protocol
Official Title: Immunological Response After Shrimp Oral Immunotherapy Treatment
ClinicalTrials.gov Identifier: NCT04552522
Protocol Version: 1.0
Protocol Date: March 2020
Sponsor: Mahidol University / Siriraj Hospital
Background
Shrimp allergy is a major cause of food-induced anaphylaxis in Asia. Current management relies on strict
avoidance and emergency treatment, but this strategy does not modify the underlying immune response.
Oral immunotherapy (OIT) has emerged as a potential disease-modifying treatment that may increase
clinical reaction thresholds and induce immunologic tolerance.
Objective
To evaluate the clinical efficacy, immunologic effects, and safety of shrimp oral immunotherapy compared
with strict avoidance in participants with confirmed shrimp allergy.
Study Design
Single-center, open-label randomized controlled trial conducted at Siriraj Hospital, Bangkok, Thailand.
Participants were randomly assigned in a 1:1 ratio to receive shrimp oral immunotherapy (OIT) or strict
avoidance.
Participants
Eligible participants were aged 12–40 years with documented immediate allergic reactions to shrimp,
positive skin prick testing or shrimp-specific IgE (≥0.35 kUA/L), and a positive oral food challenge (OFC) to
Litopenaeus vannamei.
Intervention
Participants in the intervention arm received shrimp oral immunotherapy with dose escalation every four
weeks until reaching a maintenance dose of approximately 20 grams of shrimp. The avoidance group was
instructed to avoid shrimp and other shellfish throughout the study period.
Primary Outcome
Change in eliciting dose (ED) of shrimp during oral food challenge from baseline to 12 months.
Secondary Outcomes
Secondary outcomes include changes in shrimp-specific IgE and IgG4 levels, component-resolved
allergen responses, skin test reactivity, and adverse events associated with shrimp oral immunotherapy.

Statistical Analysis
Continuous variables are summarized as median and interquartile range (IQR). Differences between
groups are analyzed using Wilcoxon rank-sum tests for continuous variables and Chi-square or Fisher’s
exact tests for categorical variables. Statistical significance is defined as P < 0.05.