TRexBio and Retension Pharmaceuticals priced initial public offerings totaling $161.7 million ahead of their Nasdaq debuts, marking the first biotech IPO pair of the quarter and the first material test of public appetite for preclinical immunology and Phase IIb hypertension programs since the fourth quarter of 2024. The dual pricing comes as the biotech IPO window shows selective reopening after fourteen months of near-dormancy.
TRexBio priced 7.5 million shares at $16.00, raising $120 million before underwriting fees. The company develops engineered regulatory T-cell therapies for autoimmune disease, with lead candidate TX-001 targeting lupus nephritis. Retension priced 4.6 million shares at $9.00, raising $41.4 million for its aldosterone synthase inhibitor program, with lead asset RET-305 in Phase IIb for resistant hypertension. Both companies had filed confidentially in November and set initial ranges in late March.
The pricing matters because it establishes a data point for what single-asset immunology and cardiovascular platforms can command in a public market that has consistently punished therapeutic breadth without Phase III visibility. TRexBio priced at the midpoint of its $15-$17 range. Retension priced at the bottom of its $9-$11 range, suggesting bookrunners found limited crossover demand between institutional accounts willing to underwrite hypertension risk at this stage. The $120 million raise gives TRexBio eighteen months of runway to Phase II readout for TX-001, expected in the second half of 2026. Retension's $41.4 million funds twelve months to interim Phase IIb data, likely fourth quarter 2025, with a need to return to markets before proof-of-concept.
Allocators should watch first-day trading performance and stabilization activity through the thirty-day lockup window. If TRexBio holds $16.00 and Retension trades below $9.00, it confirms the bifurcation between immunology platforms with plausible exits and single-mechanism cardiovascular stories trading as binary options. The next bellwether is Ascent Bio's expected pricing in mid-May for a $95 million raise on a similar regulatory T-cell platform, which will clarify whether TRexBio's midpoint pricing was founder-favorable or market-clearing.
Both companies list on Nasdaq under the tickers TREX and RETEN. Underwriters include Jefferies and Leerink for TRexBio, with Cantor and H.C. Wainwright on Retension. The last comparable dual biotech pricing day was September 2023, when two oncology-focused IPOs raised $183 million combined and both traded down 22% within ten sessions.