Efficacy and Safety of Epicutaneous Immunotherapy in Peanut-Allergic Toddlers: Open-Label Extension to EPITOPE

To assess the interim efficacy and safety of epicutaneous immunotherapy for peanut allergy with the VIASKIN patch containing 250 μg of peanut protein (VP250) from a patient cohort receiving up to 24 months of therapy.Phase 3 EPITOPE trial of VP250 included children aged 1 to 3 years with food challenge–confirmed peanut allergy. Participants, including those who received placebo, who successfully completed 12 months of EPITOPE were invited to participate in an open-label extension (OLE) in which all participants received VP250.After an additional 12 months of therapy, a double-blind, placebo-controlled food challenge (DBPCFC) to peanut was performed. Overall, 307 participants completed EPITOPE, and of these, 266 (86.6%) participants enrolled in the OLE study and 244 underwent DBPCFC at 24 months (n = 166 with 24 months of therapy; n = 78 previously received placebo so were only treated with 12 months of active therapy).Of those who received 24 months of VP250, 81.3% had an eliciting dose (ED) of 1000 mg or greater (equivalent to 3–4 large peanuts), 63.8% had an ED of 2000 mg or greater (approximately 6–8 large peanuts), and 55.9% completed the DBPCFC without meeting stopping criteria, ingesting approximately 12 to 14 peanuts. Comparing these results with the DBPCFC after only 12 months of therapy, the additional 12 months showed significant increases in the percentage of participants reaching an ED of 1000 mg or greater, or 2000 mg or greater, and in the percentage completing the challenge without a reaction. The safety profile of VP250 was also evaluated. No treatment-related anaphylaxis was noted during the second year of therapy. There were also fewer severe reactions during the DBPCFC at 24 months, compared with the DPCFC performed at 12 months. One participant in the group that transitioned from placebo to active therapy in the OLE experienced treatment-related anaphylaxis. Overall, fewer participants experienced local skin reactions in the second year compared with the first (91.4% vs 100%), but local skin reactions were common. Most of these reactions were mild or moderate and decreased in severity over time. Despite these localized reactions, compliance with VP250 was high.The interim results of the first year of the EPITOPE OLE study demonstrate that 2 years of treatment with VP250 provided gains in efficacy beyond those achieved with 12 months of treatment without new safety signals.The approach to managing food allergy has shifted from relying on allergen avoidance and passive monitoring to more proactive intervention within a paradigm of shared decision-making. Current treatment options for management of peanut allergy include oral immunotherapy (OIT) and omalizumab. However, both treatments come with drawbacks, including gastrointestinal side effects and restrictions on daily activities associated with OIT, and a requirement for regular injections in young children with omalizumab. The current study demonstrates that epicutaneous immunotherapy may soon be an attractive new option for active food allergy therapy. In addition, this study illustrates the striking immunomodulation possible by very small doses of peanut allergen when consistently and durably introduced through an epicutaneous delivery system.