Immunotherapy studies indicate that increase of the threshold to peanut can be achieved in peanut-allergic individuals; however, complete tolerance is rarely achieved. We investigated what level of protection against accidental exposure to undeclared peanut residue in food is provided after partial desensitization.
SAS (version 9.2) was used to run quantitative (probabilistic) risk modeling to determine the percentage of individual eating occasions where a predicted reaction would occur in a peanut allergic individual with a defined threshold dose that would consume cookies containing random selection of a wide distribution of trace concentrations ranging from 1 to 1000 ppm (µg/g) peanut protein. A consumption distribution from 107 cookie categories, based on dietary data recorded in the 2003-2010 National Health and Nutrition Examination Surveys from 11,497 individuals, was used to model potential exposure doses, and a total of 5,000,000 simulations was made.
Peanut-allergic individuals reacting at 1, 3, 10, or 30 mg peanut protein (one tenth of a peanut kernel) before immunotherapy will react in 16.5%, 11.8%, 6.6%, or 2.6% eating occasion, respectively. Successful increase of their threshold dose to 300 mg peanut protein or more during treatment would decrease their risk of an allergic reaction 2,063-fold, 1,475-fold, 825-fold, or 325-fold, respectively, after consumption of a peanut-contaminated cookie.
Reaching a threshold dose of 300 mg peanut protein would be a key milestone in the immunotherapy treatment of highly peanut-sensitive individuals at very high risk of allergic reactions, as they would tolerate most trace levels of undeclared peanut protein in food products.