TRB-061: A Selective TNFR2 Agonist for Inflammatory Disease

I. Executive Summary

TRB-061 is an investigational biological therapeutic being developed by TRexBio, Inc. It functions as a novel, selective agonist of Tumor Necrosis Factor Receptor 2 (TNFR2).[1] The core mechanism of action involves augmenting the activity and proliferation of tissue-resident regulatory T cells (Tregs), key mediators of immune suppression, with the goal of restoring immune homeostasis in inflamed tissues.[1] This approach contrasts with conventional therapies that often rely on broad immunosuppression. The primary indications targeted for TRB-061 are moderate-to-severe Atopic Dermatitis (AD) and Inflammatory Bowel Diseases (IBD), including Ulcerative Colitis (UC).[5]

Currently, TRB-061 is advancing through Investigational New Drug (IND)-enabling studies, positioning it as TRexBio's most advanced wholly-owned asset.[1] A Phase 1 clinical trial (NCT06934252), designed to assess safety, pharmacokinetics, and pharmacodynamics in healthy volunteers and AD patients, is anticipated to commence in the first half of 2025.[5] Preclinical studies have provided validation for this progression, demonstrating potent in vivo Treg expansion in humanized mouse models and achieving proof-of-concept in relevant animal models of colitis and skin inflammation.[1]

TRexBio, the developer, utilizes a proprietary "Deep Biology Platform" focused on human tissue immunology to identify novel targets and pathways.[1] The company secured significant Series B financing ($84 million) in late 2024, largely earmarked for TRB-061's clinical advancement, with participation from prominent strategic investors including Eli Lilly, Pfizer Ventures, and Johnson & Johnson Innovation.[5] Existing collaborations with Lilly and Johnson & Johnson further validate the company's platform technology.[4]