• Percentage of participants who tolerate the buildup stage to the planned maintenance dose of peanut SLIT [ Time Frame: At 16 to 36 weeks ] [ Designated as safety issue: Yes ]
• Peanut tolerance, as determined by OFC after being off daily SLIT for 8 weeks including differences in immunologic measures versus desensitized participants [ Time Frame: At approximately 3 years of maintenance therapy ] [ Designated as safety issue: Yes ]
• Incidence of all serious adverse events [ Time Frame: Throughout study ] [ Designated as safety issue: Yes ]
• Changes in immunologic laboratory values [ Time Frame: Throughout study ] [ Designated as safety issue: Yes ]

The purpose of this study is to evaluate the safety and immune response to daily sublingual (under the tongue) immunotherapy (SLIT) with peanut extract in adults and children with peanut allergies.

Peanut allergy is a common ailment in the United States. Research suggests that the prevalence of peanut allergy in the United States has doubled over the last 5 years. Currently, the only effective treatment for peanut allergy is a peanut-free diet and quick access to self-injectable epinephrine. The sublingual route is a potential method to administer immunotherapy for the treatment of food allergies. The intent of this study is to induce desensitization and eventually tolerance to peanut protein and evaluate the safety and immunologic effects of daily SLIT for individuals with peanut allergy. The trial will enroll a total of 40 participants. After the first 10 participants between the ages of 18 and 40 are enrolled, safety information will be reviewed. If there are no concerns the study will continue to enroll the remaining participants between the ages of 12 and 40.

This clinical trial will last about 172 to 216 weeks. Participants will be randomly assigned to receive peanut SLIT or placebo. All participants will have an entry oral food challenge (OFC). The treatment group will receive gradual dosing escalations of peanut SLIT and maintenance therapy over a 44-week period, followed by another OFC. Following the OFC, participants will be unblinded, and the placebo group will receive peanut SLIT escalated to a higher maximum dose than the first treatment group. Maintenance therapy will continue for both groups for more than 2 years.

Study visits will occur every 2 weeks during dosing escalations of peanut SLIT, followed by visits gradually spacing out during maintenance to every 12 weeks. At selected visits, a physical examination, skin prick tests, blood and urine collection, and atopic dermatitis and asthma evaluations will occur. Approximately 6 OFCs will be administered to each subject throughout the course of the study. Additionally, 10 participants will be enrolled as controls. These control participants will not receive any peanut SLIT therapy and will only have blood drawn at 3 visits throughout the course of the trial.

• Food Hypersensitivity
• Hypersensitivity
• Immediate Hypersensitivity
• Peanut Hypersensitivity

• Drug: Peanut powder
• Drug: Placebo for peanut powder

• Experimental: Oral peanut immunotherapy (in the form of peanut extract) and up to six oral food challenges as directed by the protocol
• Placebo Comparator: Placebo for peanut powder and up to six oral food challenges as directed by the protocol

• de Leon MP, Rolland JM, O'Hehir RE. The peanut allergy epidemic: allergen molecular characterisation and prospects for specific therapy. Expert Rev Mol Med. 2007 Jan 9;9(1):1-18. Review.
• Enrique E, Cisteró-Bahíma A. Specific immunotherapy for food allergy: basic principles and clinical aspects. Curr Opin Allergy Clin Immunol. 2006 Dec;6(6):466-9. Review.
• Sicherer SH, Sampson HA. Peanut allergy: emerging concepts and approaches for an apparent epidemic. J Allergy Clin Immunol. 2007 Sep;120(3):491-503; quiz 504-5. Epub 2007 Aug 8. Review.

Inclusion Criteria:

• Physician-diagnosed peanut allergy OR convincing clinical history of peanut allergy
• Reacts to a cumulative dose of 2,000 mg or less of peanut powder
• Positive peanut allergy skin prick test OR detectable serum peanut-specific IgE level
• Willing to use an acceptable method of contraception for the duration of the study
• Ability to perform spirometry maneuver in accordance with the American Thoracic Society guidelines

Exclusion Criteria:

• History of severe anaphylaxis to peanut
• Currently participating in a study using a new investigational new drug
• Participation in any interventional study for the treatment of food allergy in the 12 months prior to study entry
• Allergic to placebo ingredients (glycerin or oat flour) OR reacts to any dose of placebo during study entry OFC
• Currently in a buildup phase of any allergy immunotherapy
• Poor control of atopic dermatitis
• Moderate or severe asthma despite therapy
• Current treatment with greater than medium daily doses of inhaled corticosteroids
• Use of steroid medications
• Use of omalizumab or other nontraditional forms of allergen immunomodulatory therapy (not including corticosteroids) or biologic therapy in the 12 months prior to study entry
• Use of beta blockers, angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, or calcium channel blockers
• Inability to discontinue antihistamines for skin testing and OFCs
• History of ischemic cardiovascular disease
• History of alcohol or drug abuse
• Other significant medical conditions that, in the opinion of the investigator, prevent participation in the study
• Previous intubation due to allergies or asthma
• Uncontrolled high blood pressure
• Pregnancy or breastfeeding