Pathway to Peanut Tolerance

This is an open-label, non-randomized, two-arm trial designed to evaluate the real-world efficacy, safety, and tolerability of a pragmatic peanut oral immunotherapy (OIT) protocol for children under 18 in Hong Kong. The study addresses a significant unmet need by providing access to a treatment available overseas and aims to establish a translatable model for future food allergy treatments in the region. The intervention arm (n=100) will undergo 18 months of peanut OIT, while the control arm (n=25) will follow standard care, i.e., strict peanut avoidance for the same duration.

Eligible children aged 2-17 with a confirmed peanut allergy will be recruited from the Specialist Outpatient Clinic at the Prince of Wales Hospital and through referral from other public hospitals. Participants will be allocated to the active or control arm in a 4:1 ratio.

The primary efficacy measure is the proportion of participants in the OIT group versus the control group who achieve a desensitization level of more than 640 mg of peanut protein, as confirmed by an oral food challenge at the end of the 18-month treatment period.

Some of the key secondary objectives include to systematically document the frequency and severity of treatment-related adverse events and the proportion of participants discontinuing OIT due to these events; and to identify distinct pre- and post-treatment plasma protein biomarkers associated with successful OIT.

Inclusion criteria

• Subject's parent and/ or guardian must be able to understand and provide informed consent.
• Age 2 to 17 years of age
• Either sex
• Any race, any ethnicity
• Have a history of sensitization [positive skin prick test to peanut extract as defined by wheal size at least 3mm above control OR peanut-specific IgE ≥0.35 kUA/L]

Exclusion criteria

Individuals who meet any of these criteria are not eligible for enrolment:

• Any disorder in which adrenaline is contraindicated (such as hypertension or cardiac rhythm disorders)
• History of chronic diseases requiring therapy (other than asthma, atopic dermatitis, allergic rhinitis)
• Past or current major illness that in the opinion of the Site investigator may affect the subject's ability to participate in the study e.g. increased risk to the participant
• Concurrent treatment with any allergen immunotherapy
• Participation in any trials of therapeutic interventions for FA, or therapy with anti-IgE or other biologics within 1 year of enrolment
• Current uncontrolled or moderate to severe asthma as defined by FEV1 value <80% predicted for participants aged 7 years or older and are able to perform spirometry
• Gastrointestinal eosinophilic disorders
• Use of short-acting antihistamine (e.g. chlorpheniramine) within 3 days prior to open-labelled food challenge or skin testing, or medium-acting antihistamine (e.g. cetirizine, loratadine) within 5 days prior to open-labelled food challenge or skin testing
• Use of beta-blockers, ACE inhibitors, angiotensin-receptor blockers or calcium channel blockers