The Clinical Impact of the Basophil Activation Test to Diagnose Food Allergy

NCT05309772 | Unknown DMC

• 1 other identifier: IRAS 299511
• Study Type: interventional
• Target: 398
• Locations: 1 country
• Sites: 11

Brief Summary

The BAT Impact study is a prospective multicentre study in the UK using a biomarker-led study design to compare the incidence of adverse events (defined as allergic reactions during oral food challenges) in a randomized-controlled trial. Patients will either follow the standard-of-care (i.e. an oral food challenge in case of equivocal SPT/sIgE) or follow a basophil activation test (BAT)/mast cell activation test (MAT)-based strategy, i.e. patients with a positive BAT or MAT are dispensed of an oral food challenge (OFC) and patients with a negative BAT/MAT undergo an OFC.

Conditions

Food Allergy; Food Allergy in Infants; Food Allergy in Children; Food Allergen Sensitisation; Milk Allergy; Egg Allergy; Nut Allergy

Keywords

Food allergy; Milk allergy; Egg allergy; Nut allergy; Basophil activation test; Mast cell activation test; Diagnosis; Specific IgE; Skin prick test; Oral food challenge

Outcome Measures

Primary Outcomes (2)

• The proportion of positive oral food challenges in the biomarker arm (BAT ± MAT) compared to the standard-of-care arm

  Comparison of the ratio of positive oral food challenges in the biomarker arm compared to the standard-of-care arm.

  Up to 1 year

• Number of OFCs in the biomarker arm (BAT ± MAT) compared to the standard-of-care arm

  Comparison of the ratio of OFCs in the biomarker arm compared to the standard-of-care arm.

  Up to 1 year

Secondary Outcomes (4)

• The quality of life of children and parents at the start and at the end of the diagnostic work-up for food allergy as assessed by the Food Allergy Quality of Life Questionnaire.

  Up to 1.5 years

• Anxiety levels of parents and children before and after diagnostic work-up as assessed by the Hospital Anxiety and Depression Questionnaire.

  Up to 1.5 years

• Anxiety levels of parents and children before and after diagnostic work-up as assessed by the State Trait Anxiety Inventory.

  Up to 1.5 years

• NHS and societal costs of food allergies during the diagnostic assessment, as measured through a bespoke form.

  Up to 1.5 years

Study Arms (2)

Biomarker arm

EXPERIMENTAL

All participants will have blood taken to test for BAT/MAT. Participants with a positive BAT/MAT will dispense from oral food challenge (OFC). Participants with negative or inconclusive BAT/MAT will undergo OFC.

Diagnostic Test: Basophil activation test (BAT); Diagnostic Test: Oral food challenge (OFC)

Standard-of-care arm

ACTIVE COMPARATOR

All participants in the standard-of-care arm will have blood taken to test for BAT/MAT. Regardless of the result of BAT/MAT, all participants in this arm will undergo an oral food challenge, as per the current standard-of-care.

Diagnostic Test: Basophil activation test (BAT); Diagnostic Test: Oral food challenge (OFC)

Interventions

Basophil activation test (BAT) DIAGNOSTIC_TEST

Basophils and mast cells are the key drivers of food allergic reactions and anaphylaxis to foods. The study team have developed new tests that measure the reaction of mast cells and basophils by flow cytometry following stimulation with allergen, the BAT and the MAT: • BAT uses fresh whole blood from patients added to allergen and antibodies in a test tube. The tube containing the allergic cells are then analysed one by one to estimate how many and how much express activation markers on their surface, CD63 and CD203c. MAT uses a human mast cell line (LAD2 cells) which are human mast cells grown in the laboratory to which patients' plasma is added in order to mimic the patients' own mast cells. Sensitised LAD2 cells are then stimulated with allergen or controls and analysed by flow cytometry to assess the expression of the activation marker CD63 on the cell surface, similar to what happens in the BAT. Results of MAT will be considered only in cases of non-responding basophils.

Also known as: Mast cell activation test (MAT)

Biomarker arm; Standard-of-care arm

Oral food challenge (OFC) DIAGNOSTIC_TEST

Consumption of the food suspected of causing an allergic reaction in a medically supervised environment, starting with small amounts and progressively increasing the dose at regular intervals up to a cumulative dose corresponding to an age-appropriate portion of the food.

Biomarker arm; Standard-of-care arm

Eligibility Criteria

• Age: 6 Months - 15 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Children and young people aged 6 months to 15 years
• Suspected allergy to one of the study foods (peanut, cow's milk, egg, cashew, sesame) - defined as:
• history of clinical reaction or
• evidence of IgE sensitisation (SPT\>0mm and/or specific IgE\>=0.10 KU/L) to the respective food or
• reassessment for possible resolution of allergy to the specific food following previous diagnosis of food allergy
• Need for an oral food challengeOFC to the study food
• Oral food challengeOFC to reach amount of food protein in a typical portion size for child's age
• Consent from adults with parental responsibility and assent from children and young people in an age appropriate form.

You may not qualify if:

• Clinically significant chronic illness other than atopic diseases;
• Previous history of severe life-threatening reaction to the suspected food with documented decrease in oxygen saturation (\<90%), hypotension (≥20% reduction in systolic blood pressure) and/or admission to intensive care;
• Unwillingness to comply with study procedures, namely to undergo a diagnostic food challenge;
• Contra-indication for diagnostic food challenge, namely:
• Uncontrolled atopic diseases (e.g. eczema, asthma, rhinitis);
• Chronic medical conditions that pose significant risk in the event of anaphylaxis or treatment of anaphylaxis (e.g. cardiac disease, severe lung disease, pregnancy, mastocytosis);
• Inability to discontinue medications that might interfere with assessment or safety (e.g. antihistamines, β-agonists, β-blockers, NSAIDs, ACE inhibitor, antacids);
• Recent (within 7-14 days) treatment with systemic steroids or prolonged high-dose systemic steroids or immunosuppressants;
• Undergoing treatment with omalizumab, food or inhalant allergen immunotherapy or other systemic immunomodulatory treatment;
• Inability to stop anti-histamines prior to SPT or OFC.

Sponsors & Collaborators

• King's College London: lead
• Sandwell & West Birmingham Hospitals NHS Trust: collaborator
• Cambridge University Hospitals NHS Foundation Trust: collaborator
• NHS Lothian: collaborator
• University Hospitals, Leicester: collaborator
• Guy's and St Thomas' NHS Foundation Trust: collaborator
• University College London Hospitals: collaborator
• King's College Hospital NHS Trust: collaborator
• Manchester University NHS Foundation Trust: collaborator
• Newcastle-upon-Tyne Hospitals NHS Trust: collaborator
• Sheffield Children's NHS Foundation Trust: collaborator
• University Hospital Southampton NHS Foundation Trust: collaborator

Study Sites (11)

Sandwell and West Birmingham Hospital

Birmingham, United Kingdom

RECRUITING

Addenbrookes Hospital

Cambridge, United Kingdom

NOT YET RECRUITING

Royal Hospital for Children and Young People

Edinburgh, United Kingdom

NOT YET RECRUITING

Leicester Royal Infirmary

Leicester, United Kingdom

RECRUITING

Evelina London Children's Hospital

London, United Kingdom

RECRUITING

King's College Hospital

London, United Kingdom

NOT YET RECRUITING

University College London Hospital

London, United Kingdom

NOT YET RECRUITING

Royal Manchester Children's Hospital

Manchester, United Kingdom

NOT YET RECRUITING

Great North Children's Hospital

Newcastle, United Kingdom

NOT YET RECRUITING

Sheffield Children's Hospital

Sheffield, United Kingdom

NOT YET RECRUITING

University Hospital Southampton

Southampton, United Kingdom

RECRUITING

MeSH Terms

Conditions

Food Hypersensitivity; Milk Hypersensitivity; Egg Hypersensitivity; Nut Hypersensitivity; Disease

Interventions

Basophil Degranulation Test

Condition Hierarchy (Ancestors)

Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases; Nut and Peanut Hypersensitivity; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Immunologic Tests; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Investigative Techniques; Immunologic Techniques

Study Officials

• Alexandra Santos, MD, PhD

  King's College London

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Alexandra Santos, MD, PhD

CONTACT

+44 (0) 20 7188 6424; alexandra.santos@kcl.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Patients will be randomised using a 4:5 allocation between standard-of-care/biomarker arms. Stratified randomisation will be adopted according to recruiting centre, using a web-based allocation system.

Study Record Dates

• First Submitted: September 7, 2021
• First Posted: April 4, 2022
• Study Start: January 13, 2023
• Primary Completion: July 1, 2025
• Study Completion: July 1, 2025
• Last Updated: September 6, 2023

Record last verified: 2023-03

Data Sharing

• IPD Sharing: Will not share

Locations

GB (11)