Sublingual immunotherapy treats peanut allergy

There is renewed hope for children and adults who suffer with peanut allergy. A multicenter clinical trial of a new sublingual immunotherapy has shown promise in desensitizing severe allergic reaction to peanut powder.

Researchers from the University of North Carolina at Chapel Hill randomized 40 participants aged 12 to 37 years at testing sites in 5 states to receive daily treatments of a liquid containing either peanut powder or placebo, both in gradually increasing amounts, for 44 weeks. Patients held the liquid under their tongues for 2 minutes and then swallowed it.

All participants were administered baseline oral food challenges of up to 2 g of peanut powder to determine how much they could ingest without experiencing allergic symptoms. After 44 weeks, they received follow-up oral food challenges. Those patients who could consume either 5 g or at least 10 times more of the peanut powder than their baseline amounts were considered desensitized to peanuts.

Seventy percent of those who received peanut sublingual immunotherapy were desensitized at week 44 compared with 15% of those receiving placebo. Of 10,855 peanut doses given, 63% were symptom free; excluding oral-pharyngeal symptoms, 95% were symptom free. In addition, the median amount of peanut powder successfully tolerated increased from 3.5 mg at the beginning of the study to 496 mg at 44 weeks and 996 mg at 68 weeks.

The findings show that sublingual immunotherapy safely induced peanut desensitization in a majority of patients compared with placebo. The treatment holds promise for severely allergic children and adults whose only options are to eliminate peanuts and peanut components from their diets and to carry epinephrine injector pens in case of accidental ingestion.

The researchers caution, however, that for now the treatment should be given only by medical professionals in a carefully monitored clinical trial.

Go back to the current issue of the eConsult.