Promoting Tolerance to Common Allergens in High-Risk Children: Global Prevention of Asthma in Children (GPAC) Study

• Incidence of asthma in children at high risk for developing asthma and atopy [ Time Frame: 3 years ] [ Designated as safety issue: No ]
• effects of OMIP on the immune response to allergens [ Time Frame: 3 years ] [ Designated as safety issue: No ]

• Incidence of asthma in children at high risk for developing asthma and atopy
• effects of OMIP on the immune response to allergens

The purpose of this study is to determine whether early childhood exposure to common allergens (substances that can trigger allergies and asthma) can prevent the development of asthma in children at high risk for developing the disease.

Researchers suspect that allergies to common inhaled allergens (such as house dust mite, cat dander, and grass pollens) are a major cause of childhood asthma. Recent evidence suggests that if allergies to inhaled allergens are prevented, this can cause changes in the immune system that may inhibit the development of asthma. Although strategies to prevent allergies generally focus on avoiding the allergen, complete avoidance of the common allergens linked to asthma would require extreme measures and is impractical.

Oral mucosal immunoprevention (OMIP) therapy is an allergy treatment that can induce long-lasting immune tolerance in people already suffering from allergies. By exposing the patient to small, repeated, but increasing doses of the problem allergen over a long period of time, the patient's immune system is eventually desensitized to that particular allergen. OMIP therapy has been shown to be safe in children as young as 2 years old. This study will evaluate if OMIP therapy against common inhaled allergens is safe and effective in preventing the development of asthma in children at high risk for developing the disease. Children enrolled in this study have been diagnosed with eczema or food allergies and have a family history of eczema, allergic rhinitis, or asthma.

There are two groups in this study. Group 1 participants will receive OMIP therapy (a mixture of house dust mite, cat, and timothy grass allergens) as daily oral drops under the tongue for 1 year; Group 2 participants will receive placebo. Participants will be followed for an additional 3 years to see whether they develop allergies or asthma and to determine how OMIP affects how their immune systems respond to allergens. There will be 5 study visits in the first year and 6 visits over the next 3 years. At all visits, participants will be assessed for allergy/asthma symptoms, will be asked to complete questionnaires, and may be asked to provide blood or saliva samples.

• Asthma
• Allergic Rhinitis

• Biological: Oral mucosal immunoprevention (OMIP) therapy
  • liquid containing house dust mite, cat, and timothy grass allergens
  • drops placed under the tongue, daily for 1 year
• Biological: Placebo
  inactive form of experimental therapy containing no allergens

• Experimental: 1
  Intervention: Biological: Oral mucosal immunoprevention (OMIP) therapy
• Placebo Comparator: 2
  Intervention: Biological: Placebo

• Mascarell L, Van Overtvelt L, Moingeon P. Novel ways for immune intervention in immunotherapy: mucosal allergy vaccines. Immunol Allergy Clin North Am. 2006 May;26(2):283-306, vii-viii.
• Nelson HS. Advances in upper airway diseases and allergen immunotherapy. J Allergy Clin Immunol. 2006 May;117(5):1047-53. Epub 2006 Mar 6. Review.

Inclusion Criteria:

• Diagnosed with eczema (atopic dermatitis)
• Family history of eczema, allergic rhinitis, or asthma
• Allergy to one or more of the following: egg white, cow's milk, peanut, or soybean
• Weigh at least 9.5 kg (20.9 lbs)
• Parent or guardian willing to provide informed consent

Exclusion Criteria:

• Allergy to house dust mite, cat, or timothy grass
• Born prematurely (before 36th week's gestation)
• Previous diagnosis of asthma OR have had 3 or more distinct episodes of wheeze during the first year of life
• Chronic pulmonary disease
• Chronic disease requiring therapy
• Past or current treatment with systemic immunomodulator medication
• Past or current treatment with allergen-specific immunotherapy
• Received 10 or more days of systemic steroids in the 3 months prior to study entry
• Orofacial abnormalities that are likely to interfere with the volunteer's ability to take study treatment
• Participated in another clinical study within the 3 months prior to study entry