TRex Bio, Inc.
TRex Bio, a clinical-stage biotech focused on tissue Treg biology for autoimmune and inflammatory diseases, filed Amendment No. 1 to its S-1 for an IPO on Nasdaq under symbol "TRXB." The company plans to sell 8,333,334 shares at an estimated $14.00–$16.00 per share, targeting gross proceeds of approximately $117 million to $133 million. The offering is led by J.P. Morgan, Evercore ISI, Cantor, Stifel, Wedbush, and PacGrow, with a 30-day greenshoe for up to 1,250,000 additional shares.
- Offering 8,333,334 shares at $14.00–$16.00 per share, targeting ~$117M–$133M in gross proceeds before greenshoe.
- Underwriters hold a 30-day option to purchase up to 1,250,000 additional shares (15% of base offering).
- Lead asset TRB-061 (TNFR2 agonist) is in Phase 1b for atopic dermatitis; topline data expected mid-2027.
- TRB-071 (CD30 agonist) is in IND-enabling studies with Phase 1 initiation targeted for H1 2027.
- Lilly has indicated non-binding interest in purchasing shares up to 19.9% post-offering ownership; Lilly-partnered TRB-051 advancing to Ph2a
Price data unavailable.
A pure-play tissue Treg biology company with two wholly-owned clinical/preclinical assets and a Lilly-partnered program entering Phase 2a is testing the IPO window for early-stage immunology platforms
Joins a wave of immunology-focused biotech IPOs targeting tissue-specific Treg modulation rather than broad immunosuppression. The Lilly collaboration and potential insider participation provide external validation, but the IPO market for early-clinical-stage biotechs remains selective.
Both lead assets are early-stage: TRB-061 has no efficacy data yet (Phase 1b topline mid-2027), and TRB-071 has not entered human trials. The company has no approved products, no revenue, and is subject to full clinical, regulatory, and financing risk typical of preclinical/Phase 1 biotechs. Lilly's
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