Desensitization of peanut allergic patients by Oral-Immunotherapy (OIT) up to 3000mg peanut protein (PP) enables unlimited peanuts consumption. Some patients, however, have difficulties reaching this maintenance dosing. Knowledge regarding the long-term therapeutic efficacy of patients on lower maintenance doses is limited.
The peanut-OIT treatment protocol consisted of an in-hospital initial induction-desensitization phase, in which a maximal individualized tolerated dose was determined and then consumed daily at home. Doses were gradually increased on a monthly basis in a day-hospital care setting. Patients with technical difficulties ingesting the maintenance dose or limited due to allergic reactions were placed on lower daily maintenance doses and instructed to avoid ingesting amounts of PP above it.
Eleven patients ranging from 6-19 years, with starting doses of 12.5 (3-150) mg PP, reached maintenance doses of 1200 (600-1500) mg (median (range), respectively). Duration of OIT-treatment was 5 (3-13) months (median (range), respectively). All patients reacted during induction and 5/11 (45%) experienced reactions during home treatment, including one requiring Epi-Pen. In long-term follow-up after 14 (6-68) months (median (range), respectively), the average SPT-wheal size was reduced from 8.9 to 3.6 millimeter and only 4 subjective reactions were reported. Oral food challenges up to 3000 mg PP were successful in 10/11 patients. One patient whose maintenance dose was 600mg reacted to 2100mg PP. Full compliance to daily dose consumption was reported by 8/11 patients while 3/11 occasionally stopped for greater than a week.
Prolonged consumption of lower maintenance doses may facilitate complete desensitization in patients experiencing difficulties during peanut-OIT.