Study procedures: oral food challenges
OFCs were performed either in an open (6.2%) or double-blind, placebo-controlled (93.8%) manner (DBPCFC) by trained staff following the PRACTALL criteria (21). Allergens were blinded in a food matrix (e.g. apple sauce) and fed in seven increasing doses (amounts equal to 3 mg, 10 mg, 30 mg, 100 mg, 300 mg, 1 g and 3 g of peanut protein) over 30-minutes intervals under clinical supervision. A positive challenge outcome was defined by objective clinical reactions (e.g. urticaria/angioedema, vomiting, wheezing/stridor, rhinitis/conjunctivitis and/or a decrease in blood pressure). After completion of all 7 titration steps without the occurrence of any kind of objective allergic reaction, patients received a subsequent cumulative dose of 4.5 g of peanut on the following day, proving clinical tolerance in case of no objective symptoms.