Real-life safety of peanut oral immunotherapy: Results from a French multicenter observational study.

Background: Peanut oral immunotherapy (POIT) has been widely used in France for more than 10 years. However, the overall "real-life" safety of POIT has not been evaluated to date. Objective: We sought to describe the number, severity, and circumstances of allergic reactions (ARs) in patients undergoing POIT. Methods: We performed a retrospective multicenter study from November 2019 to July 2021 in 12 French centers, including patients with peanut allergy who were older than 3 years and treated by POIT for 6 months or more. Data collected from the patients' charts about ARs occurring during the previous year included the number, severity (using the Astier score grades 1-5), and circumstances of all immediate allergic reactions (IARs) and non-IARs. Results: Among the 295 patients included, 46 (15.6%) experienced an IAR, accounting for a total of 75 IARs. The IARs were mainly grade 1; however, 22 (29.3%) were defined as a serious systemic reaction (ie, Astier score grade ≥ 3) and 8 (10.6%) were managed by epinephrine injection at home. Proven cofactors were involved in 38 of 73 IARs (52.1%): exercise in 65.8%, fatigue in 18.4%, stress in 13.2%, irregular peanut intake in 5.3%, and pollen exposure in 5.3%. The use of epinephrine was more frequent when a cofactor was involved (0% vs 18.4%; P = .01). Among the 279 patients with available data, 32 (11.5%) experienced non-IARs, mainly chronic abdominal pain (20 [62.5%]). Conclusions: Although POIT is safe for most patients, some severe IARs influenced by cofactors may occur several months after the beginning of the process. These results highlight the overriding importance of maintaining therapeutic education, especially about risk cofactors, throughout oral immunotherapy programs.