Management of Gastrointestinal Symptoms During Oral Immunotherapy: Guidance from OUtMATCH Investigators.

Oral immunotherapy (OIT) is effective for inducing desensitization to food allergens and continues to be investigated in many clinical trials, either alone or in combination with adjunct therapies. However, adverse events (AEs) such as gastrointestinal (GI) symptoms are common during OIT. These symptoms can pose a considerable management challenge for investigators adhering to clinical trial protocols with strict study windows where extended dosing interruptions are not feasible. GI symptom management practices in the previous clinical trials have usually been left to the discretion of each study site, resulting in a wide heterogeneity of management practices that could lead to substantial variability between sites. In the Omalizumab as a Monotherapy and as Adjunct Therapy to Multi-Allergen Oral Immunotherapy (OIT) in Food Allergic Children and Adults (OUtMATCH) randomized controlled clinical trial (NCT03881696) assessing omalizumab and multiallergen OIT, a critical need for a unified approach for managing GI AEs was identified. To address this need, a subcommittee comprising investigators, both allergists and gastroenterologists, within and outside of the Consortium of Food Allergy Research, developed a working definition for persistent GI AEs during OIT along with a management plan to be used within the ongoing OUtMATCH trial. We present here the definition and management plan, along with illustrative case-based scenarios encountered during the trial. Implementing a management plan for GI AEs during OIT clinical trials has the potential to create standardization, enhance symptom monitoring, improve outcome classification, allow for stratification of AEs related to GI symptoms, and improve safety outcomes for study participants.