ABSTRACT
Rationale: To seek optimal dosing regimens for Oral immunotherapy (OIT). Methods: A retrospective chart review of 93 patients undergoing "bite proof” nut OIT dosing was undertaken. Patients were escalated to doses of 250-500mg of nut protein for a 6-12 month period and then completed a 2gm nut challenge. Results: Among 93 patients, a total of 209 2g Nut Oral Food Challenges (OFCs) were conducted. 202 of the 209 administered 2g OFCs were passed (96.65%). Among the 6 patients who did not tolerate the initial 2gm OFC, there were no obvious differentiating characteristics identified including single vs multiple food OIT administration, age, concomitant omalizumab, or change in IgE levels from baseline. 12 of the 93 patients who successfully passed the 2gm challenge elected to reduce their dose to the bite proof dosing 3x weekly. 7 of these 12 patients completed a subsequent 2gm OFC 1 year after the initial OFC. All 7 patients successfully tolerated the second 2gm OFC. Conclusions: Patients undergoing a 6-12 month course of 250-500mg daily nut protein dosing exhibited robust success in passing a 2gm OFC. Defining characteristics of patients who failed initial 2gm OFCs could not be determined due to the small number of OFC failures. A subset of patients passing the 2gm OFC demonstrated continued success in tolerating a 2gm nut challenge following a decrease in dosing frequency. Unfortunately the COVID pandemic prohibited further OFCs study of such patients. Future studies of such patients will help elucidate ideal long term OIT dosing strategies.