Tectonic Therapeutic, Inc. announced the complete results from Part A of the Phase 1b clinical trial of TX45 in patients with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”), which are being presented in a late-breaking, oral session at the European Society of Cardiology (ESC) Heart Failure 2025 Congress being held in Belgrade, Serbia. The results include the full cohort of 19 patients in part A of the Phase 1b trial of TX45, Tectonic’s lead asset and a long-acting relaxin therapy. The complete data from Part A of the Phase1b clinical trial confirmed the tolerability and hemodynamic effects of TX45 in patients with PH-HFpEF previously reported in the interim data.
The Phase 1b trial enrolled a patient population and evaluated hemodynamic endpoints which are similar to the ongoing APEX Phase 2 clinical trial (ClinicalTrials.govNCT06616974). APEX is a 24-week clinical trial in PH-HFpEF with topline results expected in 2026. New hemodynamic data reported from the Phase 1b clinical trial include the following: Echocardiograms were evaluated at baseline and at Days 2, 15 and 29.
In the clinical trial, hemodynamics were analyzed across a range of left ventricular ejection fractions (“LVEF”), including LVEF50% and LVEF 41-49%. Cardiac output increased numerically more in response to TX45 in patients with higher baseline PVR, with 16.8% improvement in patients with baseline PVR. Highlights from complete Phase 1b Part A results: Within the cohort of 19 patients with PH-HFp EF enrolled in the Phase 1b open label clinical trial of TX45, 9 patients had CpcPH, as measured by PVR>2 Wood units.
The Phase 1b open label clinical trials is designed to evaluate the safety and hemodynamic effect of single doses of TX45 in patients with group 2 pulmonary hypertension. The design of the clinical trial is as follows: after obtaining informed consent, a right heart catheter, which is the gold standard for the measurement of cardiopulmonary hemodynamics, is inserted and baseline measurements are obtained, an intravenous dose of TX45 is administered, and hemodynamic effects are evaluated over 8 hours post dose. Leveraging its proprietary technology platform called GEODe??
(GPCRs Engineered for Optimal Discovery), Tectonic is focused on developing biologic medicines that overcome the existing challenges of GPCR-targeted drug discovery and harness the human body to modify the course of disease.
