TRex Bio prices $117M IPO to support immune drug work

 Immune drugmaker TRex Bio has priced a $117 million initial public offering, joining the ranks of nearly two dozen biotechnology companies that have done so in 2026.

TRex sold 8,333,334 shares at $14 each, meeting the lower end of projections it set earlier in the week. The company begins trading Friday on the Nasdaq under the ticker symbol “TRXB.”

TRex is developing drugs that can treat diseases by calming an immune system that’s become overstimulated. The company hopes to achieve this by creating medicines that activate regulatory T cells, or “Tregs,” which guard the body from attacking itself and promote wound healing.

TRB-061 is a fusion protein that goes after a receptor on Tregs called tumor necrosis factor receptor 2. Once it finds its target, TRB-061 is designed to help those cells spur into action and multiply, soothing inflammation in the skin and gut without broadly blunting the immune system. A Phase 1 study is underway, with topline data coming in 2027, the company said in a regulatory filing.

Another drug TRex has outlined as a candidate for treating inflammatory bowel disease could enter testing next year. Called TRB-071, it’s directed at a different Treg receptor, CD30, and helps both enhance Treg activity while blocking another source of inflammation. The company has partnered with Eli Lilly and Johnson & Johnson to find new anti-inflammatory drugs. Both pharma companies have licensed or exercised options to develop experimental treatments discovered by TRex.

Lilly is TRex’s largest equity owner, holding about 24% of shares in the biotech prior to its IPO. The big drugmaker also indicated interest in buying up a portion of the startup’s IPO stock. TRex has banked $220 million in venture financing to date, including a $50 million raise earlier this year to support its ongoing Phase 1 trial.

Another biotech firm, Retension Pharmaceuticals, also went public on Thursday with an upsized $45 million offering. These two latest deals, combined with other recent IPOs, a similar number of reverse mergers and a few “SPAC” deals, show how public market investment in biotechs has “accelerated at unprecedented clip in 2026,” according to a Monday report from investment firm William Blair.

Of the 23 drug developers that have gone public in 2026, six, or a little over 25%, have been developing treatments for immune diseases, according to BioPharma Dive data.

https://www.biopharmadive.com/news/trex-bio-ipo-pricing-autoimmune-tregs/832297/