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Tectonic Therapeutic Announces Second Quarter 2026 Financial Results and Recent Business Highlights Exhibit 99.1 Enrollment completed in TX45 APEX Phase 2 clinical trial in patients with pulmonary hypertension associated with heart failure with preserved ejection fraction ( “ PH - HFpEF ” ) with topline results anticipated in early Q1 2027 TX45 APEX Phase 2 clinical trial Independent Data Monitoring Committee ( “ IDMC " ) met in July 2026 and recommended continuation of the study without modification TX2100 , a potential treatment for Hereditary Hemorrhagic Telangiectasia ( " HHT " ) , completed dosing of the six single dose healthy volunteer cohorts in the Phase la clinical trial , with topline results anticipated by end of Q3 2026 Cash and cash equivalents were $ 227.1 million as of June 30 , 2026 , including approximately $ 11.7 million in net proceeds raised from an at - the - market offering for the three months ended June 30 , 2026 , is expected to provide cash runway into Q1 2029 WATERTOWN , Mass . , August 6 , 2026 ( GLOBE NEWSWIRE ) - Tectonic Therapeutic , Inc. ( NASDAQ : TECX ) ( " Tectonic " or the " Company " ) , a clinical stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of G - protein coupled receptors ( GPCRs ) , today announced financial results for the second quarter ended June 30 , 2026 , and provided an overview of recent business highlights . " In the second quarter , we completed enrollment in our global APEX Phase 2 trial in PH - HFpEF , a critical milestone for TX45 , and we look forward to topline results in early Q1 2027 , " said Alise Reicin , M.D. , President and Chief Executive Officer of Tectonic Therapeutic . " We also completed dosing of the single dose cohorts in the TX2100 Phase 1a clinical trial in healthy volunteers . Subject to favorable safety , tolerability and pharmacokinetic results , we plan to advance TX2100 into a Phase 1b trial in patients with hematologic - support dependent HHT and a Phase 2 trial in moderate to severe HHT patients , bringing us one step closer to a first - in - class therapy for a disease with no approved treatments . " Recent Business Highlights Completed Enrollment of TX45 APEX Phase 2 Clinical Trial in PH - HFpEF Patients : In June 2026 , the Company completed enrollment for the APEX trial , a global , randomized , placebo - controlled 24 - week Phase 2 clinical trial evaluating the safety and efficacy of TX45 in patients with PH - HFpEF . In July 2026 , the Independent Data Monitoring Committee ( “ IDMC " ) met to review unblinded safety and efficacy data from the TX45 APEX Phase 2 clinical trial , including approximately 80 % of the expected patient exposure . The IDMC recommended the continuation of the trial without modification . The trial was designed to include an enriched population of a more severe disease subtype of combined pre- and post - capillary pulmonary hypertension ( “ CpcPH " ) patients with a pulmonary vascular resistance ( " PVR " ) ≥3 Wood Units ( " WU ” ) at baseline . The APEX Phase 2 clinical trial enrolled a total of 191 patients across 14 countries of which 137 patients were enrolled with CpcPH and PVR≥3 WU at baseline , consistent with the goal for this patient population to represent approximately 70 % of the overall patients enrolled in APEX . The mean baseline PVR in the overall patient population and the subset of patients with CpcPH and PVR≥3 WU was 4.2 WU¹ and 5.2 WU¹ , respectively .