Phase 2b Study of RPT904 as Monotherapy in Participants With IgE-Mediated Food Allergy

Phase 2b Study of RPT904 as Monotherapy in Participants With IgE-Mediated Food Allergy: This is a Phase 2b randomized, double-blind, placebo-controlled clinical trial evaluating RPT904, a next-generation anti-IgE monoclonal antibody, in people with food allergy. RPT904 is a long-acting antibody that may allow for dosing every 8 to 12 weeks. Approximately 100 participants between the ages of 12 and 55 with documented allergy to at least one of the following foods: peanut, milk, egg, cashew, or walnut will be enrolled. In Part 1 (24 weeks), participants will be randomly assigned to receive RPT904 every 8 or 12 weeks (plus a loading dose at Week 2), or placebo. In Part 2 (24 weeks), participants who received RPT904 will continue on their assigned dosing schedule, and those who previously received placebo will be re-randomized to receive RPT904 either every 8 or 12 weeks (plus a loading dose at Week 26). All participants will attend study visits approximately every 2-6 weeks throughout both Part 1 and Part 2 to maintain blinding, regardless of treatment group or dosing frequency. The study is being conducted at multiple sites. The primary goal is to assess whether RPT904 helps participants tolerate higher amounts of a food allergen without dose-limiting allergic symptoms during a food challenge. The study will also monitor the safety and side effects of RPT904 over time. Each participant is expected to be in the study for about 68 to 74 weeks, including screening, treatment, and follow-up.

Key Inclusion Criteria: * Participant and/or parent/legal guardian must be able to understand and provide informed consent and/or assent, as applicable. * Male or female, 12 to less than 56 years of age at screening. * Allergic to at least 1 of the following foods: peanut, milk, egg, cashew, or walnut, as confirmed by the following criteria: * a. For participants aged 12 to \