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

NCT07220811 | Recruiting Phase 2 DMC FDA Drug

• 1 other identifier: RPT904-01
• Study Type: interventional
• Target: 100
• Locations: 3 countries
• Sites: 26

Brief Summary

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.

Conditions

Ig-E Mediated Food Allergy

Keywords

Ig-E Mediated food allergy; peanut allergy; milk allergy; egg allergy; cashew allergy; walnut allergy; RPT904; placebo; double-blind placebo-controlled food challenge (DBPCFC); ozureprubart; JYB1904

Outcome Measures

Primary Outcomes (1)

• To compare the ability to consume a food without dose-limiting symptoms during a DBPCFC at the end of Part 1 after treatment with either RPT904 or placebo

  Proportion of participants who consumed a single dose of ≥600 mg (ie, a cumulative dose of ≥1044 mg) of peanut or cashew protein, or a single dose of ≥1000 mg (ie, a cumulative dose of ≥2044 mg) of milk, egg, or walnut protein without dose-limiting symptoms at Part 1 DBPCFC

  Approximately 24 weeks

Secondary Outcomes (1)

• To evaluate safety during treatment with either RPT904 or placebo

  Approximately 48 weeks

Study Arms (3)

RPT904 (Q8W)

EXPERIMENTAL

RPT904 every 8 weeks. The dose levels of RPT904 (150 mg, 300 mg, and 600 mg) within the Q8W cohort will be assigned based on participant weight and baseline total IgE level. RPT904 subcutaneous injection every 8 weeks with a loading dose at Week 2 (Part 1: 24 weeks; Part 2: 24 weeks); matching placebo at intervening visits to maintain blinding.

Drug: RPT904; Other: Placebo

RPT904 (Q12W)

EXPERIMENTAL

RPT904 every 12 weeks. The dose levels of RPT904 (150 mg, 300 mg, and 600 mg) will be assigned based on participant weight and baseline total IgE level. RPT904 subcutaneous injection every 12 weeks with a loading dose at Week 2 (Part 1: 24 weeks; Part 2: 24 weeks); matching placebo at intervening visits to maintain blinding.

Drug: RPT904; Other: Placebo

Placebo

PLACEBO COMPARATOR

Placebo subcutaneous injection on schedules matching both the Q8W and Q12W arms in Part 1 (24 weeks); RPT904 every 8 or 12 weeks with a loading dose at Week 26 on schedules matching both the Q8W and Q12W arms Part 2 (24 weeks), with matching placebo at intervening visits to maintain blinding.

Drug: RPT904; Other: Placebo

Interventions

RPT904 DRUG

Subcutaneous injection once every 8 weeks

Also known as: ozureprubart, JYB1904

RPT904 (Q8W)

Placebo OTHER

Subcutaneous injection at the intervening dosing visits

RPT904 (Q12W); RPT904 (Q8W)

Eligibility Criteria

• Age: 12 Years - 55 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• 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 \<18 years:
• i. Allergic to peanut: participant must meet all criteria below:
• \. Positive SPT (≥4 mm wheal greater than saline control) to peanut.
• \. Positive peanut IgE (≥6 kUA/L) at screening or within 3 months of screening.
• \. Positive blinded oral food challenge (OFC) to peanut during the screening DBPCFC, defined as experiencing dose-limiting symptoms at a single dose of ≤100 mg (ie, cumulative dose of ≤144 mg) of peanut protein.
• ii. Allergic to milk or egg: unable to tolerate both cooked and uncooked forms:
• \. Positive SPT (≥4 mm wheal greater than saline control) to the specific food.
• \. Positive food-specific IgE (≥6 kUA/L) at screening or within 3 months of screening.
• \. Positive blinded OFC to the specific food during the screening DBPCFC, defined as experiencing dose-limiting symptoms at a single dose of ≤300 mg (ie, cumulative dose of ≤444 mg) of food protein.
• iii. Allergic to cashew: participant must meet all criteria below:
• \. Positive SPT (≥4 mm wheal greater than saline control) to cashew. OR
• \. Positive cashew IgE (≥6 kUA/L) at screening or within 3 months of screening. AND

You may not qualify if:

• Clinically significant lab abnormalities at screening.
• Sensitivity or suspected/known allergy to any component of the active or placebo OFC material (excluding the test allergens peanut, milk, egg, walnut, and cashew being tested), or drugs related to RPT904 (eg, monoclonal antibodies, polyclonal gamma globulin).
• Uncontrolled or severe asthma/wheezing at screening.
• Current use of oral, IM, or IV corticosteroids, tricyclic antidepressants, or β-blockers (oral or topical).
• Past or current immunotherapy to any study foods within 6 months of screening.
• Treatment with immunomodulatory therapy within 6 months of screening.
• Currently in the "build-up phase" of inhalant allergen immunotherapy (i.e., not yet on maintenance). Note: individuals on stable maintenance dosing may be eligible.
• Past or current medical problems (eg, severe latex allergy), chronic diseases (other than asthma/wheezing, atopic dermatitis, or rhinitis) requiring therapy (eg, heart disease, diabetes), abnormal physical findings or lab results not listed above that, in the Principal Investigator's opinion, may increase study related risks, hinder protocol compliance, or impact data quality or interpretation .

Sponsors & Collaborators

• RAPT Therapeutics, Inc.: lead

Study Sites (26)

Arkansas Children's

Little Rock, Arkansas, 72202, United States

RECRUITING

Sean N. Parker Center for Allergy and Asthma Research

Palo Alto, California, 94304, United States

RECRUITING

Asthma & Allergy Associates, P.C.

Colorado Springs, Colorado, 80907, United States

RECRUITING

National Jewish Health

Denver, Colorado, 80206, United States

RECRUITING

Children's National Hospital

Washington D.C., District of Columbia, 20010, United States

RECRUITING

University of South Florida

Tampa, Florida, 33613, United States

RECRUITING

Children's Healthcare of Atlanta - Center for Advanced Pediatrics

Atlanta, Georgia, 30329, United States

RECRUITING

Boston's Children's Hospital

Boston, Massachusetts, 02115, United States

RECRUITING

Clinical Research Institute, Inc

Minneapolis, Minnesota, 55402, United States

RECRUITING

Northwell Health

Great Neck, New York, 11021, United States

RECRUITING

Icahn School of Medicine at Mount Sinai

New York, New York, 10029, United States

RECRUITING

University of North Carolina at Chapel Hill Clinical and Translational Research Center( CTRC)

Chapel Hill, North Carolina, 27599, United States

RECRUITING

Cincinnati Children's Hospital

Cincinnati, Ohio, 45229, United States

RECRUITING

Vanderbilt University

Nashville, Tennessee, 37232, United States

RECRUITING

St Vincent's Hospital Sydney

Darlinghurst, New South Wales, 2010, Australia

RECRUITING

Children's Hospital at Westmead

Westmead, New South Wales, 2145, Australia

RECRUITING

Queensland Children's Hospital

South Brisbane, Queensland, 4101, Australia

RECRUITING

Women's & Children's Hospital

North Adelaide, South Australia, 5006, Australia

RECRUITING

Monash Medical Centre

Clayton, Victoria, 3168, Australia

RECRUITING

Royal Melbourne Hospital

Parkville, Victoria, 3050, Australia

RECRUITING

The Royal Children's Hospital

Parkville, Victoria, 3052, Australia

RECRUITING

Perth Children's Hospital

Nedlands, Western Australia, 6009, Australia

RECRUITING

Fiona Stanely Hospital

Perth, Western Australia, 6150, Australia

RECRUITING

BC Children's Hospital

Vancouver, British Columbia, V6H3V4, Canada

RECRUITING

Halton Pediatric Allergy

Burlington, Ontario, L7L6W6, Canada

RECRUITING

Ottawa Allergy Research Corporation

Ottawa, Ontario, K1H1E4, Canada

RECRUITING

MeSH Terms

Conditions

Peanut Hypersensitivity; Milk Hypersensitivity; Egg Hypersensitivity

Condition Hierarchy (Ancestors)

Nut and Peanut Hypersensitivity; Food Hypersensitivity; Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Masking Details: Double blind
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 22, 2025
• First Posted: October 24, 2025
• Study Start: October 22, 2025
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): January 1, 2028
• Last Updated: May 4, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

CA (3); US (14); AU (9)