Prolonged Avoidance of Peanuts after Peanut Oral Immunotherapy May Reverse Its Effects

SAN DIEGO, CA – Research presented at the 2014 Annual Meeting of the American Academy of Allergy, Asthma & Immunology (AAAAI) continues to provide insight into the questions that surround possible food allergy treatments being investigated. In particular, one study suggested

that prolonged avoidance of peanuts following peanut oral immunotherapy may reverse the effects achieved with the treatment.

“We know that oral immunotherapy can lead to desensitization in peanut allergic subjects, but one of things we’re trying to uncover is what happens once oral immunotherapy is stopped for varying lengths of time,” said Immediate Past-President A. Wesley Burks, MD, FAAAAI.

Dr. Burks was one of the investigators involved in a small study at University of North Carolina at Chapel Hill that tried to find answers. Subjects who were on oral immunotherapy performed double-blind placebo-controlled food challenges with peanut, while continuing their daily oral immunotherapy treatment, to assess desensitization.Then, the subjects avoided peanut in their diets for either one or three months, at which time a second double-blind placebo-controlled food challenge was given.

The 20 subjects in the study all passed the food challenge, but the results of the second food challenge differed between the group who avoided peanut for one month and the group who avoided it for three months. Of the subjects that a voided peanut for one month following the first food challenge, 16 of 16 passed the second food challenge. However, only one of four subjects

who avoided peanut for three months passed the second food challenge.

To get a better sense of what was occurring, the researchers looked at levels of basophil activation and skin prick tests to peanut. Basophils are a type of cell involved in the allergic response. Increased basophil activation was measured between the time of the first and second food challenges for the group who avoided peanut for three months but not for the group who avoided it for one month. When comparing basophil activation between the groups, significant differences were seen at the time of the second food challenge but not the first.