Peanut desensitization achievable with low doses of maintenance oral immunotherapy

Arnon Elizur

Long-term and lower maintenance doses of peanut oral immunotherapy are an effective form of protection against peanut allergy for those with difficulties with standard oral immunotherapy, with nearly all patients succeeding with a 3,000 mg dose of peanut protein at follow-up, according to a study presented at the annual meeting of the American Academy of Allergy, Asthma & Immunology.

“Overall, the success rate of peanut oral immunotherapy is very high, with approximately 85% of patients able to freely consume peanuts and over 90% of patients able to consume at least a single peanut at the end of treatment,” Arnon Elizur, MD, from the department of pediatrics at Tel Aviv University’s Sackler School of Medicine, Israel, told Infectious Diseases in Children. “Those who fail treatment remain peanut allergic and need to avoid peanuts and carry an epinephrine autoinjector.”

To better understand the long-term efficacy of low-dose peanut oral immunotherapy, the researchers conducted a study in which oral immunotherapy was initiated within a hospital setting for the induction-desensitization phase. In this phase, researchers administered the highest tolerable dose of oral immunotherapy, and then patients were directed to continue this dosage once per day at home.

If technical difficulties or limitations were experienced due to trouble consuming the maintenance dose or allergic reactions, patients were then prescribed lower doses of oral immunotherapy and were recommended not to ingest amounts of peanut protein above their maintenance doses.

Of the 11 patients included in the study between the ages of 6 and 19 years, those who began with a median of 12.5 mg (range: 3-150 mg) of peanut protein were able to reach median maintenance doses of 1,200 mg (range: 600-1,500 mg). Reactions were observed in all patients, and 45% of patients had a reaction in their homes. One of these patients required treatment with an epinephrine autoinjector.

At follow-up (median: 14 months; range: 6-68 months), Elizur and colleagues observed that the average SPT-wheal size dropped from 8.9 mm to 3.6 mm, with four reported subjective reactions. Nearly all (10 of 11 patients) were successful in oral food challenges up to 3,000 mg of peanut protein. The one patient who was not able to reach 3,000 mg of peanut protein had a maintenance dose of 600 mg and experienced a reaction at 2,100 mg of peanut protein.

Compliance was inconsistent for three patients, who would occasionally halt treatment for longer than 1 week. The remaining eight patients reported full compliance.

Elizur suggests that if patients are interested in this treatment method, they should be referred to an allergist.

“This treatment is associated with frequent adverse effects including reactions that require epinephrine,” he said. “Oral immunotherapy should be given only by allergists experienced in food allergy and in specialized centers.” – by Katherine Bortz

Reference:

Nachshon L, et al. Abstract 750. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 2-5, 2017; Orlando.

Disclosure: Infectious Diseases in Children was unable to confirm relevant financial disclosures prior to publication.