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iFAAM: The Impact of Proton-pump Inhibitors (Antacids) on Threshold Dose Distributions

Phase 4
Completed
Conditions
Food Allergy
Interventions
Drug: Placebo
Registration Number
NCT02552537
Lead Sponsor
University of Zurich
Brief Summary

In patients with a walnut allergy double blind placebo controlled food challenge with walnut will be combined with the intake of proton pump inhibitor (PPI) or with placebo to assess the impact of PPI on threshold level and on clinical manifestation.

Detailed Description

1. detailed case history, blood sampling and prick testing with different foods will performed.

2. double blind food provocation with with three meals containing either placebo or walnut in walnut allergic patients will be performed.

3. the provocation will be combined with the intake of drug (omeprazole) or placebo (mannitol) blinded in capsules.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
44
Inclusion Criteria
  • signed informed consent, history of walnut allergy,minimum age 18 years
Exclusion Criteria
  • • Known hypersensitivity or allergy to Omeprazole, other proton pump inhibitors, mannitol, ingredients of placebo meal

    • Drugs not allowed during the study due to proved interaction with Omeprazole: Digoxin, Clopidogrel, Methotrexate, Antiretroviral drugs, Diazepam, Cilostazol, Phenytoin, Warfarin (R-Warfarin) and other Vitamin K antagonists, Phenytoin, Tacrolimus, Clarithromycin, voriconazole, Rifampicin and Hypericum
    • Drugs not allowed due to interference with the food challenge (or shortest interval between last treatment and food challenge)
  • corticosteroids systemically (2 weeks)

  • antihistamines (3 days) except hydroxyzine (10 days)

  • ketotifen (2 weeks)

  • betablocker (1 day)

  • angiotensin converting enzyme (ACE) inhibitors (2 days)

  • omalizumab (2 months)

    • Women who are pregnant or breast feeding
    • Intention to become pregnant during the course of the study
    • Lack of safe contraception, defined as: female participants of childbearing potential, not using and not willing to continue using a medically reliable method of contraception for the entire study duration, such as oral, injectable, or implantable contraceptives, or intrauterine contraceptive devices
    • Please note that female participants who are surgically sterilised / hysterectomised or post-menopausal for longer than 2 years are not considered as being of child bearing potential.
    • Uncontrolled asthma, forced expiratory volume <70% predicted value
    • Acute allergic disease
    • Chronic urticaria
    • Mastocytosis
    • Other clinically significant concomitant disease states (major organic or infectious diseases, e.g., renal failure, hepatic dysfunction, cardiovascular disease, acute febrile infection),
    • Known or suspected non-compliance, drug or alcohol abuse,
    • Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant,
    • Participation in another study with investigational drug within the 30 days preceding and during the present study

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
PlaceboPlacebopatients will take Mannitol, in capsules, once a day, during five days before walnut challenge
OmeprazoleOmeprazolepatients will take Omeprazole 40mg, in capsules, once a day, during five days before walnut challenge
Primary Outcome Measures
NameTimeMethod
amount of walnuts that induces an allergic reaction assessed in milligramup to 18 months

The amount of walnut which induces an allergic reaction in walnut allergic patients will be assessed in milligram by titrated challenges under concommitant intake of therapeutic doses of omeprazole versus placebo

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (2)

University Hospital Zurich

🇨🇭

Zurich, Switzerland

Hospital Clinico San Carlos

🇪🇸

Madrid, Spain

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