WATERTOWN, Mass. — October 29, 2025 — Leads & Copy — Tectonic Therapeutic, Inc. (NASDAQ: TECX) announced positive results from its Phase 1b Part B clinical trial of TX45 in patients with Group 2 PH‑HFrEF.
The study showed that a single dose of TX45 was well tolerated and improved both left heart function and pulmonary hemodynamics.
The Phase 1b Part B trial was designed to evaluate TX45 in the expanded patient population of Group 2 PH-HFrEF, building on the positive results from the Phase 1b Part A trial of TX45 in patients with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”).
Tectonic is currently conducting the APEX Phase 2 clinical trial to evaluate TX45 over a 24-week treatment period in patients with PH-HFpEF, with topline results expected in 2026 (ClinicalTrials.gov NCT06616974).
Alise Reicin, M.D., President and Chief Executive Officer of Tectonic, stated the results open the potential to expand into an additional patient population with significant unmet need and no approved therapies.
John Teerlink, M.D., Professor of Medicine, University of California, San Francisco, noted the study demonstrated clinically important changes across multiple hemodynamic measures, showing the broad potential of TX45.
TX45 is an Fc-relaxin fusion protein that activates the RXFP1 receptor, a target of the hormone relaxin.
Key results from the Phase 1b Part B trial include improvements in pulmonary capillary wedge pressure (PCWP), pulmonary vascular resistance (PVR), cardiac output (CO), total pulmonary resistance (TPR), and mean pulmonary artery pressure (mPAP).
The company will host a webcast today, October 29th at 4:30 p.m. ET.
Contacts: Investors: Dan Ferry, LifeSci Advisors, daniel@lifesciadvisors.com, (617) 430-7576; Media: Kathryn Morris, The Yates Network, kathryn@theyatesnetwork.com, (914) 204-6412
Source: Tectonic Therapeutic, Inc.
