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.