Sublingual Immunotherapy for Peanut Allergy and Induction of Tolerance
Condition: Peanut Hypersensitivity; Food Hypersensitivity; Food Allergy; Peanut Allergy
MeSH terms: Hypersensitivity; Food Hypersensitivity; Peanut Hypersensitivity
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      The goal of this study will be to increase the reaction threshold (desensitization) of peanut
      allergic children using peanut sublingual immunotherapy and to determine if the nonreactive
      state of the immune system persists after treatment has been discontinued (tolerance).
    

Detailed description: 
      Allergy to peanuts and tree nuts affects approximately 1.4% of the population. Allergic
      reactions to peanut can be severe and life threatening and account for the vast majority of
      fatalities due to food-induced anaphylaxis. At present, there are no viable treatment options
      for patients with peanut allergy. The current standard of care is strict dietary elimination
      and emergency preparedness with an anaphylaxis kit in the event of an accidental reaction.

      Our group and others have shown that oral immunotherapy can provide protection from
      anaphylaxis to a variety of food proteins. In addition, our ongoing research has demonstrated
      that sublingual immunotherapy to peanut provides a safe, alternative mode of immunotherapy to
      reduce allergic reaction rates (desensitization) during oral food challenge (OFC) to peanut.
      The goal of this study will be to desensitize peanut allergic children using peanut
      sublingual immunotherapy and to determine if the nonreactive state of the immune system
      persists after treatment has been discontinued (tolerance). Children ages 1-11 years will be
      enrolled following an entry double blind, placebo controlled food challenge (DBPCFC).

      After at least 48 months of peanut SLIT study drug, subjects will undergo a second DBPCFC to
      5000 mg of peanut protein to assess desensitization.

        -  Subjects who are not desensitized are those who are not able to consume more than the
           MCRT without symptoms, which has been defined as 300 mg of peanut protein. Subjects who
           consume less than 300 mg of peanut protein without symptoms will stop peanut SLIT and
           conclude the study. These subjects will not undergo any additional study procedures
           including the remaining protocol DBPCFCs and will be recommended to resume a strict
           peanut avoidance diet.

        -  Subjects who are able to consume more than 300 mg of peanut protein will be randomized
           to an interval between 1 and 17 weeks during which all peanut including peanut SLIT
           study drug will be discontinued. This period of avoidance will be followed by a third
           DBPCFC to 5000 mg of peanut protein to evaluate for the loss of the desensitization
           effect. After this final DBPCFC, the study will be completed for these subjects. At the
           primary investigators clinical discretion, they will be recommended to transition to a
           daily peanut food equivalent to maintain the desensitized effect.

      Outcome variables of interest include response to double blind, placebo controlled food
      challenges, skin prick testing, peanut specific serum immunoglobin E (IgE), immunoglobin G
      (IgG), and immunoglobin G4 (IgG4) and salivary immunoglobin A (IgA), T and B cell responses,
      basophil hyporesponsiveness, quality of life, and adverse events.
    

Intervention name(s): Liquid peanut extract (Peanut SLIT)
Intervention type(s): Drug
Intervention description(s): Liquid peanut extract will be administered under the tongue
Other intervention name(s): Peanut SLIT - active arm
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment