Food Challenge at Home or in Medical Practice - the FoodCHOMP Study

Austin Health

Status: Enrolling

Conditions: Food Allergies

Treatments: Diagnostic Test: In-Clinic Food Challenge; Diagnostic Test: Home-Based Food Challenge

Study type: Interventional

Funder types: Other

Identifiers

NCT06916819

111750/Austin-2024

Details and patient eligibility

About

This is a pilot, multi-centre, randomised clinical trial evaluating the safety and feasibility of a home-based oral food challenge in adults with low-risk food allergy labels. Eligible participants are aged 18 years or older and have a self-reported food allergy with negative skin prick testing to the implicated food. Participants will be randomised to either a home-based or standard in-clinic food challenge. The primary aim is to determine the safety of home challenges, measured by the rate of immune-mediated adverse events. Secondary aims include feasibility of recruitment and delivery, protocol adherence, quality of life, and food reintroduction outcomes.

Full description

Food allergies are highly prevalent and contribute to significant patient anxiety and healthcare utilisation. Many individuals carry food allergy labels without confirmation through diagnostic food challenge, resulting in unnecessary food avoidance. In-clinic food challenges are the current standard for confirming tolerance but are resource-intensive and often delayed. This study evaluates whether selected low-risk adults can safely complete a structured oral food challenge at home.

This is a pilot, multi-centre, randomised controlled trial conducted at two tertiary allergy centres in Victoria, Australia (Austin Health and Royal Melbourne Hospital). Adults referred with a reported food allergy will undergo clinical assessment and skin prick testing. Those with negative skin testing (<3mm wheal) to the implicated food and meeting other eligibility criteria will be randomised 1:1 to either:

• Intervention: Home-based oral food challenge over five days, beginning with a single supervised dose in-clinic and followed by four incremental doses at home with daily clinical follow-up.
• Control: Standard in-clinic oral food challenge using a protocol derived from PRACTALL and ASCIA guidelines.

The primary outcome is the proportion of participants experiencing an immune-mediated adverse event during food challenge. Secondary outcomes include feasibility metrics (eligibility, recruitment, delivery), non-immune mediated adverse events, protocol adherence, quality of life (measured by FAQLQ-12), time to challenge, and real-world food reintroduction.

The study will enrol 120 participants (60 per arm). Outcomes will inform the design of a future non-inferiority trial and may support integration of home challenges into routine practice for selected patients.

Enrollment: 120 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Negative (<3mm) fresh or extract skin testing to the food implicated within their allergy label
2. Aged greater than 18 years

Exclusion criteria

• Evidence of prior sensitisation to challenge food 0 Defined as previously positive skin testing or allergen specific IgEs if available
• Pregnancy
• Patients with poorly controlled asthma - defined as an ACQ5 scores >1 at the time of enrolment
• Patients with a history of food reactions that is not-consistent with an IgE mediated process; i.e. exclusively gastrointestinal symptoms, FPIES
• Patients with a clear history of food-dependent exercise induced anaphylaxis
• Patients on a concurrent medication which may influence the outcome of the challenge;
• Antihistamine therapy; Patients receiving more than stress dose steroids (i.e. > 50mg QID hydrocortisone [or steroid equivalent]); Omalizumab
• Any other illness that, in the investigator's judgement, will substantially increase the risk associated with subject's participation in this study

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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120 participants in 2 patient groups

In-Clinic Food Challenge (Control Arm)

Other group

Description:

Participants randomised to the control arm will undergo a standard in-clinic oral food challenge conducted under direct medical supervision. The protocol used is derived from the PRACTALL consensus and ASCIA position statements and involves administration of increasing doses of the implicated food at 20-30 minute intervals over a 2-3 hour period. Observation continues for 1-2 hours post final dose. The challenge is performed in a hospital outpatient clinic equipped for anaphylaxis management. The food challenged is selected by the participant from their eligible food allergy labels.

Treatment:

Diagnostic Test: In-Clinic Food Challenge

Home-Based Food Challenge (Intervention Arm)

Experimental group

Description:

Participants randomised to the intervention arm will undertake a structured home-based oral food challenge over five consecutive days. This begins with an initial supervised dose administered in clinic under medical observation (60-minute monitoring period). Participants will then self-administer increasing doses of the implicated food at home each subsequent day using a standardised protocol adapted from PRACTALL and ASCIA guidelines. Dose intervals are 24 hours to reduce risk of cumulative reactions. Participants are provided with written instructions, emergency action plans, and have daily phone follow-up with allergy nursing staff during the challenge. The challenge food is selected by the participant from their eligible food allergy labels.

Treatment:

Diagnostic Test: Home-Based Food Challenge