TECX

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 1a 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., Aug. 06, 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. Completed Dosing of Single Dose Cohorts in Phase 1a Clinical Trial of TX2100 in Healthy Volunteers: In July 2026, the Company completed dosing of the six single dose cohorts in the Phase 1a clinical trial of TX2100 in healthy volunteers. The randomized, placebo-controlled, double-blind, single ascending-dose trial is intended to characterize safety and tolerability, with pharmacokinetics assessed as a secondary endpoint. TX2100 is a VHH-Fc antagonist of the APJ (apelin) receptor, a GPCR involved in pro-angiogenic signaling, and is being developed as a potential treatment for Hereditary Hemorrhagic Telangiectasia (HHT). Upcoming Milestones TX2100 Phase 1a Topline Results Expected by End of Q3 2026 with Phase 2 Planned in Early 2027: The Company expects to report topline results for the TX2100 Phase 1a clinical trial in healthy volunteers by the end of Q3 2026, with detailed data planned to be subsequently presented at a scientific meeting. Subject to favorable safety, tolerability and pharmacokinetic results, Tectonic plans to advance TX2100 into an open-label Phase 1b clinical trial in patients with hematologic-support dependent HHT and a placebo-controlled, Phase 2 clinical trial in moderate-to-severe HHT patients, with endpoints expected to include epistaxis, hemoglobin, hematologic support, and other endpoints relevant to HHT. Phase 1b and Phase 2 trials are planned to run in parallel, with the Phase 2 trial anticipated to begin in early 2027. TX45 APEX Phase 2 Trial Ongoing with Topline Results Expected Early Q1 2027: The global, randomized, placebo-controlled 24-week APEX Phase 2 trial is ongoing, evaluating subcutaneous TX45 in patients with PH-HFpEF, including an enriched population with combined pre- and post-capillary pulmonary hypertension (CpcPH). The primary endpoint is change in pulmonary vascular resistance (PVR) from baseline in the CpcPH subgroup (PVR ≥3 Wood Units). APEX patient enrollment is complete with topline results expected early Q1 2027. Overview of Financial and Operating Results Cash Position: As of June 30, 2026, cash and cash equivalents were $227.1 million, compared to $236.9 million as of March 31, 2026. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents will provide a cash runway into Q1 2029, including through the Phase 2 topline readouts of TX45 in PH-HFpEF and PH-ILD, and through significant clinical milestones in the TX2100 development program. Research and Development Expenses: Research and development expenses were $18.0 million for the three months ended June 30, 2026, as compared to $17.2 million for the three months ended June 30, 2025. The increase was primarily the result of contract research and contract development and manufacturing organizations costs related to the ongoing Phase 2 clinical trials of TX45 and employee-related expenses due to an increase in non-cash, stock-based compensation expense and increase in headcount. General and Administrative Expenses: General and administrative expenses were $6.2 million for the three months ended June 30, 2026, as compared to $5.2 million for the three months ended June 30, 2025. The increase was primarily the result of higher employee-related expenses driven by higher non-cash, stock-based compensation. Net Loss: For the three months ended June 30, 2026, the Company had a net loss of $22.3 million compared to a net loss of $20.0 million for the three months ended June 30, 2025. ¹ Baseline characteristics are preliminary and subjective to change. About Group 2 Pulmonary Hypertension in HFpEFThe World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure, which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and CpcPH. CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in PVR. Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About Group 3 Pulmonary Hypertension and PH-ILDGroup 3 is PH due to chronic lung disease and Tectonic is focused on a Group 3 subtype, called PH-ILD where PH develops in patients who have ILD. ILD is a group of rare conditions causing inflammation and scarring in the lungs. It is believed that a combination of factors leads to the formation of PH-ILD, including lung fibrosis, chronic hypoxia, vascular remodeling and other factors that lead to worsening exercise capacity. PH-ILD has worse survival than ILD without PH. There are currently two approved treatments for PH-ILD, both of which contain the active ingredient treprostinil administered via nebulizer or dry powder inhaler. About TX45, a long-acting Fc-relaxin fusion proteinTX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Hereditary Hemorrhagic Telangiectasia (HHT)HHT is a rare, inherited vascular disorder affecting an estimated 75,000 people in the United States. HHT is the second most common inherited bleeding disorder and a disease for which there are currently no approved therapies. It is characterized by fragile, abnormal blood vessels that lead to recurrent bleeding, which can reduce quality of life, result in emergency room visits and hospitalizations, as well as chronic anemia requiring frequent iron infusions and/or blood transfusions. Many patients with HHT also develop arteriovenous malformations (AVMs) in vital organs such as the lungs, brain, and liver that, if left untreated, are at risk of rupturing and can result in serious and potentially life-threatening complications including lung or brain hemorrhage, stroke, heart failure, or death. Despite being a rare disease and the second most common inherited bleeding disorder, there are currently no approved therapies. About TX2100, a VHH-Fc fusion antagonist antibodyTX2100, is a VHH-Fc fusion antagonist antibody that binds to the APJ receptor (also known as the apelin receptor; APLNR), a GPCR that mediates signaling by the pro-angiogenic peptide hormone apelin. APJ represents a differentiated approach for the potential treatment of HHT. APJ is a selective anti-angiogenic target that is primarily expressed in endothelial cells and is generally quiescent under normal physiological conditions, but is upregulated during pathologic angiogenesis, including in HHT preclinical models. TX2100 is designed as a selective APJ antagonist intended to inhibit disease-associated angiogenic signaling with the goal of providing a more favorable safety profile compared to less selective anti-angiogenic approaches. Anti-angiogenic agents have demonstrated activity in HHT preclinical models and in patients, and APJ antagonism has shown activity in multiple HHT preclinical models, supporting development of TX2100 for this indication. About TectonicTectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit https://tectonictx.com/ and follow @TectonicTx on X (formerly Twitter) and LinkedIn. Forward-Looking StatementsThis press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 2 clinical trials for its lead product candidate, TX45, in Group 2 PH-HFpEF and in Group 3 PH-ILD and the ongoing Phase 1 clinical trial for TX2100; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed for the quarter ended June 30, 2026 and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. Contacts: Investors:Dan FerryLifeSci [email protected](617) 430-7576 Media:Kathryn MorrisThe Yates [email protected](914) 204-6412

TX45 APEX Phase 2 patient enrollment in PH-HFpEF is nearing completion with topline results anticipated in late Q4 2026 or early Q1 2027 TX2100 advanced into Phase 1a healthy volunteer clinical trial in February 2026 as a potential treatment for Hereditary Hemorrhagic Telangiectasia (“HHT”), and as of April 2026, four cohorts have been dosed with topline results expected by the end of Q3 2026 TX45 ALPINE Phase 2 clinical trial initiated in Pulmonary Hypertension in Heart Failure associated with Interstitial Lung Disease (“PH-ILD,” Group 3 PH), with first site activated in February 2026 and screening initiated in March 2026, expanding TX45 into a second pulmonary hypertension indication Strengthened leadership with the appointment of François Nader, M.D., as Chair of the Board and Jessica Chutter, as independent board director, enhancing governance and strategic oversight as the Company advances its pipeline Cash and cash equivalents were $236.9 million as of March 31, 2026, expected to provide cash runway into Q4 2028 WATERTOWN, Mass., May 07, 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 first quarter ended March 31, 2026, and provided an overview of recent business highlights. "During Q1 2026, we made meaningful progress advancing both TX45 and TX2100 across key clinical milestones, including dosing the first subjects in our Phase 1a trial of TX2100 in HHT, continued dosing of patients in the TX45 APEX Phase 2 trial and initiating our TX45 ALPINE Phase 2 trial in PH-ILD ," said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic Therapeutic. "We believe TX2100 represents a novel, first-in-class approach in a disease with significant unmet need. Looking ahead, we remain focused on executing our ongoing clinical trials and advancing both programs toward important topline readouts.” Recent Business Highlights Initiated Phase 1a Clinical Trial of TX2100 in HHT: In February 2026, the Company initiated dosing in its Phase 1a clinical trial of TX2100 in healthy volunteers. The randomized, placebo-controlled, double-blind, ascending-dose trial is intended to characterize safety and tolerability, with pharmacokinetics assessed as a secondary endpoint. TX2100 is a VHH-Fc antagonist of the APJ (apelin) receptor, a GPCR involved in pro-angiogenic signaling, and is being developed as a potential treatment for HHT. As of April 2026, the Company has dosed four cohorts of healthy volunteers. Conducted KOL Webinar Focused on TX2100 in HHT: In February 2026, the Company hosted a virtual KOL event featuring Hanny Al-Samkari, M.D. (Massachusetts General Hospital, Harvard Medical School), which reviewed the clinical landscape, unmet need, and therapeutic rationale for TX2100 in HHT, including mechanistic insights and supporting preclinical data. A replay of the webinar is available here. Initiated Phase 2 Clinical Trial of TX45 in PH-ILD: In February 2026, the Company began clinical execution of its Phase 2 clinical trial of TX45 in patients with PH-ILD, with the first site activated and screening initiated. The 16-week, open-label trial is expected to enroll up to 25 patients and will evaluate change from baseline in pulmonary vascular resistance (“PVR”) at Week 16 as the primary endpoint. TX45 is administered subcutaneously every four weeks and is designed to address multiple aspects of PH-ILD pathophysiology, including vasodilation, inflammation, vascular remodeling, and fibrosis. Appointed François Nader, M.D., as Chair of the Board: In February 2026, the Company appointed François Nader, M.D., as Chair of the Board. Dr. Nader brings extensive biopharmaceutical leadership and public company experience, including serving as CEO of NPS Pharmaceuticals and overseeing its ~$5.2 billion acquisition by Shire, strengthening the Company’s board as it advances its clinical pipeline and strategic priorities. Appointed Jessica Chutter, as Independent Board Director: In April 2026, the Company appointed Jessica Chutter to its Board of Directors effective as of the Company’s 2026 annual meeting of stockholders. Ms. Chutter brings more than four decades of experience in healthcare investment banking, most recently at Morgan Stanley, with deep expertise advising biotechnology and pharmaceutical companies on strategic positioning and capital market execution, further strengthening the Company’s board. Upcoming Milestones TX2100 Phase 1a Results Expected in 3Q 2026 with Phase 2 Planned in Early 2027: The Company now expects to report topline results from the ongoing Phase 1a trial of TX2100 in healthy volunteers by the end of the third quarter of 2026. Subject to favorable safety, tolerability and pharmacokinetic results, the Company plans to advance TX2100 into a Phase 2 proof-of-concept trial in patients with moderate-to-severe HHT in early 2027, with endpoints expected to include epistaxis, anemia and hematologic support, and other HHT measures. TX45 APEX Phase 2 Trial Ongoing with Results Expected Late Q4 2026 or Early Q1 2027: The global, randomized, placebo-controlled 24-week APEX Phase 2 trial is ongoing, evaluating subcutaneous TX45 in patients with pulmonary hypertension associated with heart failure with preserved ejection fraction (PH-HFpEF), including an enriched population with combined pre- and post-capillary pulmonary hypertension (CpcPH). The primary endpoint is change in pulmonary vascular resistance (PVR) from baseline in the CpcPH subgroup (PVR ≥3 Wood Units). APEX patient enrollment is nearing completion with topline data anticipated in late Q4 2026 or early Q1 2027. Overview of Financial and Operating Results Cash Position: As of March 31, 2026, cash and cash equivalents were $236.9 million, compared to $253.8 million as of December 31, 2025. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents will provide a cash runway into Q4 2028, including through the Phase 2 readout for TX45 in PH-HFpEF and PH-ILD, and the progression of TX2100 for HHT into clinical development. Research and Development Expenses: Research and development expenses were $20.9 million for the three months ended March 31, 2026, as compared to $13.0 million for the three months ended March 31, 2025. The increase was primarily the result of CRO and CDMO costs related to the ongoing Phase 2 clinical trial of TX45 and employee-related expenses due to an increase in non-cash, stock-based compensation expense and increase in headcount. General and Administrative Expenses: General and administrative expenses were $6.4 million for the three months ended March 31, 2026, as compared to $5.3 million for the three months ended March 31, 2025. The increase was primarily the result of higher employee-related expenses driven by higher non-cash, stock-based compensation. Net Loss: For the three months ended March 31, 2026, the Company had a net loss of $25.2 million compared to a net loss of $15.9 million for the three months ended March 31, 2025. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure, which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and CpcPH. CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in PVR. Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About Group 3 Pulmonary Hypertension and PH-ILD Group 3 is PH due to chronic lung disease and Tectonic is focused on a Group 3 subtype, called PH-ILD where PH develops in patients who have ILD. ILD is a group of rare conditions causing inflammation and scarring in the lungs. It is believed that a combination of factors leads to the formation of PH-ILD, including lung fibrosis, chronic hypoxia, vascular remodeling and other factors that lead to worsening exercise capacity. PH-ILD has worse survival than ILD without PH. There are currently two approved treatments for PH-ILD, both of which contain the active ingredient treprostinil administered via nebulizer or dry powder inhaler. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Hereditary Hemorrhagic Telangiectasia (HHT) HHT is a rare, inherited vascular disorder affecting an estimated 75,000 people in the United States. HHT is the second most common inherited bleeding disorder and a disease for which there are currently no approved therapies. It is characterized by fragile, abnormal blood vessels that lead to recurrent bleeding, which can reduce quality of life, result in emergency room visits and hospitalizations, as well as chronic anemia requiring frequent iron infusions and/or blood transfusions. Many patients with HHT also develop arteriovenous malformations (AVMs) in vital organs such as the lungs, brain, and liver that, if left untreated, are at risk of rupturing and can result in serious and potentially life-threatening complications including lung or brain hemorrhage, stroke, heart failure, or death. Despite being a rare disease and the second most common inherited bleeding disorder, there are currently no approved therapies. About TX2100, a VHH-Fc fusion antagonist antibody TX2100, is a VHH-Fc fusion antagonist antibody that binds to the APJ receptor (also known as the apelin receptor; APLNR), a GPCR that mediates signaling by the pro-angiogenic peptide hormone apelin. APJ represents a differentiated approach for the potential treatment of HHT. APJ is a selective anti-angiogenic target that is primarily expressed in endothelial cells and is generally quiescent under normal physiological conditions, but is upregulated during pathologic angiogenesis, including in HHT preclinical models.TX2100 is designed as a selective APJ antagonist intended to inhibit disease-associated angiogenic signaling with the goal of providing a more favorable safety profile compared to less selective anti-angiogenic approaches. Anti-angiogenic agents have demonstrated activity in HHT preclinical models and in patients, and APJ antagonism has shown activity in multiple HHT preclinical models, supporting development of TX2100 for this indication. About Tectonic Tectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit https://tectonictx.com/and follow @TectonicTx on X (formerly Twitter) and LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 2 clinical trials for its lead product candidate, TX45, in Group 2 PH-HFpEF and in Group 3 PH-ILD and the ongoing Phase 1 clinical trial for TX2100; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed for the quarter ended March 31, 2026 and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412 Tectonic Therapeutic, Inc. Condensed Consolidated Statements of Operations and Comprehensive Loss (in thousands, except per share data) (unaudited) Tectonic Therapeutic, Inc. Select Condensed Consolidated Balance Sheet Data (in thousands) (unaudited) *Working capital is defined as current assets less current liabilities

Announced positive topline results from TX45 Phase 1b acute hemodynamic clinical trial in patients with Group 2 Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”) in October 2025. Topline results showed TX45 was well tolerated and improved both left heart function and pulmonary hemodynamics in patients with Group 2 PH-HFrEF TX2100 advanced into Phase 1a healthy volunteer clinical trial, randomizing the first subject in February 2026, as a potential treatment for Hereditary Hemorrhagic Telangiectasia (“HHT”) TX45 advanced into Phase 2 clinical trial in February 2026 with first site activated and opened for screening patients with Pulmonary Hypertension associated with Interstitial Lung Disease (“PH-ILD”, Group 3 PH) to potentially broaden the therapeutic scope of TX45 Announced the appointment of François Nader, M.D., MBA, as an independent director to Board of Directors, effective April 1, 2026, at which time he will also assume the role of Chair of the Board TX45 APEX Phase 2 clinical trial topline results expected in 2026 in patients with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”) Cash and cash equivalents were approximately $253.8 million as of December 31, 2025, expected to provide cash runway into Q4 2028 WATERTOWN, Mass., Feb. 26, 2026 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”), 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 fourth quarter and full year ended December 31, 2025, and provided an overview of recent business highlights. “Over the last 12 months, we have made significant progress expanding our clinical pipeline. In February 2026 we advanced our second program, TX2100, a potential novel treatment for patients with HHT, and dosed the first patient in a Phase 1a clinical trial in normal healthy volunteers. This marks an important milestone for Tectonic which now has two programs in clinical development to address patient populations with high unmet need and no approved therapy,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic Therapeutic. “We continued to advance TX45 through a series of important clinical and operational milestones, and we expect topline results from our ongoing APEX Phase 2 clinical trial in PH-HFpEF patients in 2026. Furthermore, in February 2026, Tectonic initiated its second TX45 Phase 2 clinical trial to evaluate TX45 in patients with PH-ILD.” Recent Business Highlights Positive Topline Results from Part B of the TX45 Phase 1b Clinical Trial: In October 2025, Tectonic announced positive topline results from Part B of the TX45 Phase 1b clinical trial in 14 patients with Group 2 PH-HFrEF. TX45 was well tolerated and demonstrated a 29.2% reduction in pulmonary capillary wedge pressure (“PCWP”) and a 17.3% improvement in cardiac output. In the subpopulation with combined pre- and post-capillary pulmonary hypertension (“CpcPH”), who have elevated pulmonary vascular resistance (“PVR”) and more severe disease, TX45 also demonstrated reductions in PVR. TX2100 HHT Phase 1a Healthy Volunteer Clinical Trial Randomized First Subject in February 2026: TX2100 is a VHH-Fc fusion antagonist antibody that binds to the APJ receptor (also known as the apelin receptor; APLNR), a GPCR that mediates signaling by the pro-angiogenic peptide hormone apelin. TX2100 is being developed as a potential therapy for HHT, the second most common inherited bleeding disorder affecting an estimated 75,000 people in the United States. In February 2026, Tectonic randomized the first subject in the randomized, placebo-controlled, double-blind ascending-dose Phase 1a clinical trial in normal healthy volunteers. Primary endpoints include safety and tolerability, with secondary endpoints evaluating pharmacokinetics. TX45 PH-ILD Phase 2 Clinical Trial Opened for Screening in February 2026: PH-ILD (Group 3 pulmonary hypertension) is a rare disease characterized by limited therapeutic options and high mortality. In February 2026, the first site was activated and opened for screening in the 16-week, open-label, repeat-dose Phase 2 clinical trial to evaluate TX45’s safety and hemodynamic effects in up to 25 patients. The clinical trial will initiate at a 300 mg dose of TX45 administered subcutaneously every four weeks, with the primary efficacy endpoint defined as change from baseline in PVR at Week 16. TX45 is designed to target multiple components of PH-ILD pathophysiology, including pulmonary vasodilation, anti-inflammatory activity, vascular remodeling and anti-fibrotic effects. Hosted Key Opinion Leader (KOL) Webinar: In February 2026, Tectonic hosted a virtual KOL event featuring Hanny Al-Samkari, MD (Massachusetts General Hospital, Harvard Medical School), who joined Tectonic’s Chief Scientific Officer to discuss the unmet medical need, clinical context, and therapeutic rationale for TX2100 in Hereditary Hemorrhagic Telangiectasia (HHT), including the target, mechanistic rationale and supporting preclinical evidence. A replay of the webinar can be accessed here. Upcoming Milestones Ongoing TX2100 Phase 1a Clinical Trial Topline Results Expected in Q4 2026: Tectonic expects topline results for the Phase 1a clinical trial of TX2100 in healthy volunteers in the fourth quarter of 2026. Assuming adequate safety and PK are established, Tectonic plans to initiate a Phase 2 proof-of-concept clinical trial in moderate to severe HHT patients with frequent epistaxis and anemia in early 2027. The goal of the trial will be to evaluate improvement in epistaxis, anemia, hematological support, and other HHT endpoints. Tectonic is also planning a Phase 1b clinical trial to explore the safety and efficacy (epistaxis, anemia, and hematological support) of TX2100 in patients with severe HHT. Ongoing TX45 APEX Phase 2 Clinical Trial Topline Results Expected in 2026: The global, randomized, placebo-controlled 24-week APEX Phase 2 clinical trial is evaluating the safety and efficacy of subcutaneous TX45 in patients with PH-HFpEF, enriched for CpcPH. The primary endpoint is change from baseline in PVR in the CpcPH population with PVR ≥3 Wood Units, with approximately 70% of enrolled patients targeted to meet the enriched criteria. APEX Phase 2 topline results are expected in 2026. Overview of Financial and Operating Results Cash Position: As of December 31, 2025, cash and cash equivalents were $253.8 million, compared to $268.4 million as of September 30, 2025. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents will provide a cash runway into Q4 2028, including through the Phase 2 readout for TX45 in PH-HFpEF and PH-ILD, and the progression of TX2100 for HHT into clinical development. Research and Development Expenses: Research and development expenses were $16.3 million for the three months ended December 31, 2025, as compared to $9.2 million for the three months ended December 31, 2024. The increase was primarily the result of CRO costs related to the ongoing Phase 2 clinical trial of TX45 and employee-related expenses due to an increase in non-cash, stock-based compensation expense. General and Administrative Expenses: General and administrative expenses were $5.2 million for the three months ended December 31, 2025, as compared to $4.8 million for the three months ended December 31, 2024. Net Loss: For the three months ended December 31, 2025, Tectonic had a net loss of $19.2 million compared to a net loss of $12.4 million for the three months ended December 31, 2024. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure, which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and CpcPH. CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in PVR. Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About Group 3 Pulmonary Hypertension and PH-ILD Group 3 is PH due to chronic lung disease and Tectonic is focused on a Group 3 subtype, called PH-ILD where PH develops in patients who have ILD. ILD is a group of rare conditions causing inflammation and scarring in the lungs. It is believed that a combination of factors leads to the formation of PH-ILD, including lung fibrosis, chronic hypoxia, vascular remodeling and other factors that lead to worsening exercise capacity. PH-ILD has worse survival than ILD without PH. There are currently two approved treatments for PH-ILD, both of which contain the active ingredient treprostinil administered via nebulizer or dry powder inhaler. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Hereditary Hemorrhagic Telangiectasia (HHT) HHT is a rare, inherited vascular disorder affecting an estimated 75,000 people in the United States. HHT is the second most common inherited bleeding disorder and a disease for which there are currently no approved therapies. It is characterized by fragile, abnormal blood vessels that lead to recurrent bleeding, which can reduce quality of life, result in emergency room visits and hospitalizations, as well as chronic anemia requiring frequent iron infusions and/or blood transfusions. Many patients with HHT also develop arteriovenous malformations (AVMs) in vital organs such as the lungs, brain, and liver that, if left untreated, are at risk of rupturing and can result in serious and potentially life-threatening complications including lung or brain hemorrhage, stroke, heart failure, or death. Despite being a rare disease and the second most common inherited bleeding disorder, there are currently no approved therapies. About TX2100, a VHH-Fc fusion antagonist antibody TX2100, is a VHH-Fc fusion antagonist antibody that binds to the APJ receptor (also known as the apelin receptor; APLNR), a GPCR that mediates signaling by the pro-angiogenic peptide hormone apelin. APJ represents a differentiated approach for the potential treatment of HHT. APJ is a selective anti-angiogenic target that is primarily expressed in endothelial cells and is generally quiescent under normal physiological conditions, but is upregulated during pathologic angiogenesis, including in HHT preclinical models.TX2100 is designed as a selective APJ antagonist intended to inhibit disease-associated angiogenic signaling with the goal of providing a more favorable safety profile compared to less selective anti-angiogenic approaches. Anti-angiogenic agents have demonstrated activity in HHT preclinical models and in patients, and APJ antagonism has shown activity in multiple HHT preclinical models, supporting development of TX2100 for this indication. About Tectonic Tectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow @TectonicTx on X (formerly Twitter) and LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 2 clinical trials for its lead product candidate, TX45, in Group 2 PH-HFpEF and in Group 3 PH-ILD and the ongoing Phase 1 clinical trial for TX2100; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s annual report on Form 10-K filed for the year ended December 31, 2025 and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412

Positive topline data from Part B of the TX45 Phase 1b trial demonstrated improvements in both left heart function and pulmonary hemodynamics in patients with Group 2 Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”) Expect to initiate TX2100 Phase 1 clinical trial in healthy volunteers in Q1’2026 as a potential treatment for Hereditary Hemorrhagic Telangiectasia (“HHT”) TX45 PH-ILD Phase 2 clinical trial is planned to initiate in 2026 to evaluate TX45’s safety and hemodynamic effects in patients with Pulmonary Hypertension associated with Interstitial Lung Disease (“PH-ILD”, Group 3 PH) to expand the therapeutic breadth of TX45 Ongoing TX45 APEX Phase 2 clinical trial in patients with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”) continues to enroll; topline results expected in 2026 Cash and cash equivalents were $268.4 million as of September 30, 2025, expected to provide cash runway into Q4’2028 WATERTOWN, Mass., Nov. 06, 2025 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”), 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 third quarter ended September 30, 2025, and provided an overview of recent business highlights. “Our team continued to advance our lead asset TX45 with the positive topline data from Part B of our Phase 1b study in patients with HFrEF. Following our recent presentation of the full Part A data set at the ESC Heart Failure 2025 Congress, the improvements demonstrated in both left heart function and pulmonary hemodynamics across both PH-HFrEF and PH-HFpEF populations suggest TX45 has the potential to be effective in a broad patient population,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic. “Enrollment continues in our global APEX Phase 2 trial in PH-HFpEF, and we expect to report topline results from that study in 2026.” Recent Business Highlights Positive Topline Results from Part B of the TX45 Phase 1b Clinical Trial: In October 2025, positive topline results from Part B of the TX45 Phase 1b clinical trial in 14 patients with PH-HFrEF were announced. TX45 was well tolerated in the overall study population and demonstrated a 29.2% reduction in pulmonary capillary wedge pressure (PCWP) and a 17.3% improvement in cardiac output. In the subpopulation with combined pre- and post-capillary pulmonary hypertension (“CpcPH”) who have an elevated pulmonary vascular resistance (PVR) and more severe disease, TX45 demonstrated a 19.7% reduction in PVR in patients with a PVR≥ 3 Wood Units and a 10.3% reduction in PVR in patients with a PVR≥ 2 Wood Units. PCWP and PVR are endpoints known to correlate with exercise capacity, morbidity and mortality in this patient population. Upcoming Milestones TX2100 GPCR Antagonist Phase 1 Clinical Trial Initiation for HHT Expected Q1’2026: TX2100 is a GPCR targeting biotherapeutic being developed as a potential treatment for HHT, the second-most common genetic bleeding disorder. The in-life portion of the IND-enabling non-human primate GLP toxicology studies are now complete. We expect to initiate a Phase 1 clinical trial in healthy volunteers for TX2100 in Q1’2026. TX45 Pulmonary Hypertension associated with Interstitial Lung Disease (“PH-ILD”) Phase 2 Clinical Trial Initiation Expected in 2026: PH-ILD (Group 3 PH) is an orphan disease with limited treatment options and a high mortality rate. In 2026, Tectonic plans to initiate a 16-week, open label, repeat dose, Phase 2 clinical trial to evaluate TX45’s safety and hemodynamic effects in up to 25 patients with PH-ILD. The study is being initiated at a dose of TX45 300 mg every four weeks administered subcutaneously, with the primary efficacy endpoint being the change from baseline in PVR at Week 16. TX45 is designed to address key aspects of PH-ILD’s disease pathophysiology, including pulmonary vasodilation, anti-inflammatory, remodeling and anti-fibrotic activity. Ongoing TX45 APEX Phase 2 Clinical Trial Results Expected in 2026: The global, randomized, placebo-controlled 24-week APEX Phase 2 clinical trial is designed to evaluate the safety and efficacy of TX45 administered subcutaneously in patients with PH-HFpEF, enriched for CpcPH. The primary efficacy endpoint of the trial is the change from baseline in PVR in the CpcPH with PVR≥3 Wood Units population, and the trial aims to enroll 70% of patients in the enriched population of CpcPH with a PVR≥3. The clinical trial is now over 50% enrolled and topline results are expected in 2026. Overview of Financial and Operating Results Cash Position: As of September 30, 2025, cash and cash equivalents were $268.4 million, compared to $287.4 million as of June 30, 2025. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents will provide a cash runway into Q4’2028, including through the Phase 2 readout for TX45 in PH-HFpEF and PH-ILD, and the progression of TX2100 for HHT into clinical development. Research and Development Expenses: Research and development expenses were $16.9 million for the three months ended September 30, 2025, as compared to $14.3 million for the three months ended September 30, 2024. The increase was primarily the result of the discovery, development and manufacturing of TX2100 and employee-related expenses due to an increase in non-cash, stock-based compensation expense. General and Administrative Expenses: General and administrative expenses were $5.0 million for the three months ended September 30, 2025, as compared to $5.3 million for the three months ended September 30, 2024. Net Loss: For the three months ended September 30, 2025, the Company had a net loss of $19.0 million compared to a net loss of $17.7 million for the three months ended September 30, 2024. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of PH. Tectonic’s initial focus has been on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure, which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated post-capillary PH (“IpcPH”) and Combined pre- and post-capillary PH (“CpcPH”). CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in Pulmonary Vascular Resistance (“PVR”). Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About Group 3 Pulmonary Hypertension and PH-ILD The World Health Organization has defined 5 groups of PH. Group 3 is PH due to chronic lung disease. Tectonic is focused on a Group 3 subtype, called PH-ILD where PH develops in patients who have ILD. ILD is a group of rare conditions causing inflammation and scarring in the lungs. It is believed that a combination of factors leads to the formation of PH-ILD, including lung fibrosis, chronic hypoxia, vascular remodeling and other factors that lead to worsening exercise capacity. PH-ILD has worse survival than ILD without PH. There are currently two approved treatments for PH-ILD, both of which contain the active ingredient treprostinil administered via nebulizer or dry powder inhaler. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Tectonic Tectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow us on LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 1b and Phase 2 clinical trials for its lead program, TX45, in Group 2 PH-HFpEF and Group 2 PH-HFrEF and its planned Phase 2 clinical trial for TX45 in PH-ILD; the Company’s planned initiation of a Phase 1 clinical trial for TX2100; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed with the SEC on November 6, 2025, and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. For more information, please visit www.tectonictx.com and follow @TectonicTx on X (formerly Twitter) and LinkedIn. Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412

TX45 PH-ILD Phase 2 clinical trial is planned to initiate in 2026 to evaluate TX45’s safety and hemodynamic effects in subjects with Pulmonary Hypertension associated with Interstitial Lung Disease (“PH-ILD”, Group 3 PH) to expand the therapeutic breadth of TX45 Complete results from Part A of the TX45 Phase 1b clinical trial presented at ESC Heart Failure 2025 confirmed TX45’s tolerability profile and improvements in left ventricular function and pulmonary hemodynamics in subjects with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”) Part B of the TX45 Phase 1b clinical trial in subjects with Group 2 Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”) completed enrollment; topline results are expected in early Q4’2025 Ongoing TX45 APEX Phase 2 clinical trial continues to enroll; topline results expected in 2026 TX2100 is expected to initiate a Phase 1 clinical trial in healthy volunteers in Q1’2026 Cash and cash equivalents were $287.4 million as of June 30, 2025, including the private placement net proceeds raised in February 2025, expected to provide cash runway into Q4’2028 WATERTOWN, Mass., Aug. 07, 2025 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”), 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, 2025, and provided an overview of recent business highlights. “Today our team is excited to announce PH-ILD as an additional indication for TX45 that we plan to explore in a Phase 2, proof of concept trial. PH-ILD is a devastating disease with high mortality, significant unmet medical need and limited therapeutic alternatives. TX45’s preclinical and hemodynamic data from Part A of the Phase 1b trial in Group 2 PH-HFpEF supports expanding into PH-ILD,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic. “Additionally, we have completed enrollment in Part B of our TX45 Phase 1b trial in subjects with PH-HFrEF, with topline results expected in early Q4’2025. In parallel, enrollment continues in our global TX45 APEX Phase 2 trial in PH-HFpEF, with topline results expected in 2026.” Recent Business Highlights Positive Complete Results from Part A of the TX45 Phase 1b Clinical Trial: In May 2025, complete results from Part A of the TX45 Phase 1b clinical trial in 19 subjects with PH-HFpEF were presented as an oral late-breaking presentation at the European Society of Cardiology (ESC) Heart Failure 2025 Congress. In the overall study population, TX45 demonstrated a 19% reduction in pulmonary capillary wedge pressure (PCWP) and an 18.5% improvement in cardiac output, and a >30% reduction in pulmonary vascular resistance (PVR) in subjects with combined pre- and post-capillary pulmonary hypertension (CpcPH), a more severe disease subtype. Added to Russell 3000® Index: In June 2025, Tectonic was added to the Russell 3000® Index as part of FTSE Russell’s annual reconstitution. Inclusion in the index broadens the company’s exposure to institutional investors and reflects its growing market capitalization. Completed Enrollment in Part B of the TX45 Phase 1b Clinical Trial: Part B is evaluating TX45 in subjects with PH-HFrEF. Enrollment has completed in the clinical trial, following the first subject dosing in March 2025. Upcoming Milestones TX45 Phase 1b Part B Topline Results Expected Early Q4’2025 TX2100 GPCR Antagonist Phase 1 Clinical Trial Initiation for Hereditary Hemorrhagic Telangiectasia (“HHT”) Expected Q1’26: TX2100 is a GPCR targeting biotherapeutic being developed as a potential treatment for HHT, the second-most common genetic bleeding disorder. TX2100 is expected to initiate a Phase 1 clinical trial in healthy volunteers in Q1’2026 following the conclusion of IND-enabling studies. TX45 PH-ILD Phase 2 Clinical Trial Initiation Expected in 2026: In 2026, Tectonic plans to initiate a 16-week, open label, repeat dose, Phase 2 clinical trial to evaluate TX45’s safety and hemodynamic effects in approximately 20 subjects with Pulmonary Hypertension (“PH”) associated with Interstitial Lung Disease (“ILD”), known as PH-ILD (Group 3 PH). PH-ILD is an orphan disease with limited treatment options and a high mortality rate. We believe TX45’s mechanism is well suited to PH-ILD’s disease pathophysiology because of its pulmonary vasodilation, anti-inflammatory, remodeling and anti-fibrotic activity. The TX45 PH-ILD Phase 2 trial is being initiated to evaluate TX45 300 mg every two weeks subcutaneous administration in PH-ILD subjects, with the primary efficacy endpoint being the change from baseline in PVR at Week 16. Ongoing TX45 APEX Phase 2 Clinical Trial Results Expected in 2026: The global, 24-week APEX Phase 2 clinical trial, a randomized, placebo-controlled trial designed to evaluate the safety and efficacy of TX45 administered subcutaneously in subjects with PH-HFpEF, enriched for CpcPH, continues to enroll, with topline results expected in 2026. Overview of Financial and Operating Results Cash Position: As of June 30, 2025, cash and cash equivalents were $287.4 million, compared to $306.2 million as of March 31, 2025. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents, will provide a cash runway into Q4’2028, including through key Phase 1b and Phase 2 readouts for TX45, and the progression of TX2100 in HHT into clinical development. Research and Development Expenses: Research and development expenses were $17.2 million for the three months ended June 30, 2025, as compared to $7.1 million for the three months ended June 30, 2024. The increase was primarily the result of increased CRO and CDMO costs related to the Phase 1b and Phase 2 clinical trials for TX45 and the discovery, development and manufacturing of TX2100. General and Administrative Expenses: General and administrative expenses were $5.2 million for the three months ended June 30, 2025, as compared to $4.3 million for the three months ended June 30, 2024. The increase was primarily due to an increase in non-cash stock-based compensation during the period. Net Loss: For the three months ended June 30, 2025, the Company had a net loss of $20.0 million compared to a net loss of $12.7 million for the three months ended June 30, 2024. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of PH. Tectonic’s initial focus has been on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure, which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated post-capillary PH (“IpcPH”) and Combined pre- and post-capillary PH (“CpcPH”). CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in Pulmonary Vascular Resistance (“PVR”). Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About Group 3 Pulmonary Hypertension and PH-ILD The World Health Organization has defined 5 groups of PH. Group 3 is PH due to chronic lung disease. Tectonic is focused on a Group 3 subtype, called PH-ILD where PH develops in patients who have ILD. ILD is a group of rare conditions causing inflammation and scarring in the lungs. It is believed that a combination of factors leads to the formation of PH-ILD, including lung fibrosis, chronic hypoxia, vascular remodeling and other factors that lead to worsening exercise capacity. PH-ILD has worse survival than ILD without PH. There are currently two approved treatments for PH-ILD, both of which contain the active ingredient treprostinil administered via nebulizer or dry powder inhaler. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Tectonic Tectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow us on LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 1b and Phase 2 clinical trials for its lead program, TX45, in Group 2 PH-HFpEF and Group 2 PH-HFrEF and its planned Phase 2 clinical trial for TX45 in PH-ILD; the Company’s planned initiation of a Phase 1 clinical trial for TX2100; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed with the SEC on August 7, 2025, and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. For more information, please visit www.tectonictx.com and follow @TectonicTx on X (formerly Twitter) and LinkedIn. Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412

Data confirmed TX45’s tolerability profile and improvements in left ventricular function and pulmonary hemodynamics in patients with Group 2 Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”) In new echocardiographic analysis, TX45 treatment resulted in sustained hemodynamic effects for 29 days TX45 improved cardiac and pulmonary hemodynamics in PH-HFpEF patients across a range of left ventricular ejection fractions (“LVEF”), including LVEF≥50% and LVEF 41-49% WATERTOWN, Mass., May 17, 2025 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”) today 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. Interim data for 16 patients in the Phase 1b trial was previously reported in a press release on January 30, 2025. The complete data from Part A of the Phase 1b clinical trial confirmed the tolerability and hemodynamic effects of TX45 in patients with PH-HFpEF previously reported in the interim data. Based on the complete dataset in PH-HFpEF, a single intravenous dose of TX45 was well tolerated, with no serious or severe adverse events. In the overall study population, TX45 achieved a 19.0% reduction in pulmonary capillary wedge pressure (“PCWP”), an endpoint known to correlate with exercise capacity, morbidity and mortality in patients with heart failure. In the subpopulation with combined pre- and post-capillary pulmonary hypertension (“CpcPH”) who have an elevated Pulmonary Vascular Resistance (“PVR”) and more severe disease, TX45 demonstrated >30% reduction in PVR, which along with PCWP is correlated to exercise capacity and mortality in this patient population. The Phase 1b trial enrolled a patient population and evaluated hemodynamic endpoints which are similar to the ongoing APEX Phase 2 clinical trial (ClinicalTrials.gov NCT06616974). APEX is a 24-week clinical trial in PH-HFpEF with topline results expected in 2026. New hemodynamic data reported today from the Phase 1b clinical trial include the following: Echocardiograms were evaluated at baseline and at Days 2, 15 and 29. Following the administration of TX45, sustained improvements in echocardiogram endpoints were observed consistent with improved hemodynamics. Increased tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/SPAP), a marker of PVR, and right ventricular fractional area of change (RVFAC), a marker of right ventricular function, were observed on all days post treatment compared to baseline demonstrating a sustained effect for 29 days after single dose administration. In the clinical trial, hemodynamics were analyzed across a range of left ventricular ejection fractions (“LVEF”), including LVEF≥50% and LVEF 41-49%. Both subpopulations showed similar improvements in PCWP (19.7% and 18.4%, respectively) and cardiac output (18.3% and 18.7%, respectively), as well as improvement in pulmonary hemodynamics following administration of TX45. Cardiac output increased numerically more in response to TX45 in patients with higher baseline PVR, with 16.8% improvement in patients with baseline PVR<2 wood units, 20.5% with baseline PVR≥2 and 24.5% with baseline PVR≥3. “We are enthusiastic about the potential of TX45 as a treatment for patients with Group 2 pulmonary hypertension. In particular, we are very encouraged that the echocardiographic analysis demonstrated sustained hemodynamic effects of TX45 out to 29 days,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic. “Additionally, the positive and consistent hemodynamic effects across a range of LVEF confirmed that TX45 is well positioned to address the full spectrum of PH-HFpEF patients. We look forward to the topline data from Part B of the Phase 1b study in another type of pulmonary hypertension patients, those with Heart Failure with reduced Ejection Fraction (HFrEF), expected in the second half of 2025.” Marcella K. Ruddy, M.D., Chief Medical Officer of Tectonic commented, “These results from the Phase 1b study show the promising therapeutic profile of TX45, offering patients a potential best-in-class therapy for Group 2 pulmonary hypertension, a disease with high morbidity, mortality and no approved treatments. Additionally, these data continue to support our hypothesis that TX45 may provide the greatest benefit to patients with CpcPH, based on data showing strong improvement in pulmonary hemodynamics and cardiac output relative to baseline PVR.” Highlights from complete Phase 1b Part A results Within the cohort of 19 patients with PH-HFpEF enrolled in the Phase 1b open label clinical trial of TX45, 9 patients had CpcPH, as measured by PVR>2 Wood units. Hemodynamic measures evaluating left ventricular function included PCWP, Cardiac Output (“CO”) and Stroke Volume (“SV”). Hemodynamic measures evaluating the pulmonary vasculature included PVR, Total Pulmonary Resistance (“TPR”) and mean Pulmonary Artery Pressure (“mPAP”). Safety Results: TX45 was well tolerated with no serious or severe adverse events, discontinuations, infusion reactions or drug-related adverse events. There were no clinically significant changes in vital signs, physical exam or safety laboratory values. Transient asymptomatic decreases in blood pressure were observed over the first 24 hours after TX45 dosing. Hemodynamic Results: TX45 administration resulted in meaningful improvement in both left ventricular function and pulmonary hemodynamics, representing a differentiated profile for TX45 compared to other PAH drugs that are pulmonary vasodilators but have not shown improvement in left ventricular function and have not shown efficacy in PH-HFpEF. TX45 achieved the following improvements in left ventricular function: PCWP decreased 19.0% [95% CI, -26.1% to -11.9%]. CO increased 18.5% [95% CI, 10.2% to 26.9%]. TX45 achieved the following improvements in pulmonary hemodynamics: PVR decreased 32.0% [95% CI, -35.9% to -28.1%] and 35.5% (95%CI, -38.6% to -32.5%) in the subgroup of patients with baseline PVR≥2 and baseline PVR≥3, respectively. TPR decreased 28.7% [95% CI, -34.1% to -22.1%] in the overall population. Mean pulmonary artery pressure decreased 16.8% [95% CI, -20.8% to -12.8%] in the overall population. As a relaxin therapeutic, the differentiated mechanism of TX45 improved both left ventricular function and pulmonary hemodynamics, which most strongly matches the more severe pathophysiology of patients with CpcPH. About the TX45 Phase 1b clinical trial in Group 2 pulmonary hypertension The Phase 1b open label clinical trial is designed to evaluate the safety and hemodynamic effect of single doses of TX45 in patients with Group 2 pulmonary hypertension. Part A evaluated the effect of TX45 in PH-HFpEF and Part B will evaluate effects of TX45 in Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”). 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. Participants are then followed for 45 days post dose for safety and exploratory biomarker endpoints. Part A of the trial has completed. Part B enrollment is ongoing with topline data expected in the second half of 2025. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”). In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and Combined pre- and post-capillary PH (“CpcPH”). CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in Pulmonary Vascular Resistance (“PVR”). Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Tectonic Tectonic is a biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of G-protein coupled receptors (“GPCRs”). 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow on LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 1b and Phase 2 clinical trials for its lead program, TX45, in Group 2 PH-HFpEF. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s Quarterly Report on Form 10-Q filed with the SEC on May 8, 2025, and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. For more information, please visit www.tectonictx.com and LinkedIn. CONTACT: Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412

Interim analysis from the TX45 Phase 1b Part A trial demonstrated meaningful improvements in both left ventricular function and pulmonary hemodynamics in patients with Group 2 Pulmonary Hypertension in Heart Failure with Preserved Ejection Fraction (“PH-HFpEF”) Full results from the Phase 1b Part A trial will be presented on May 17, 2025 at the European Society of Cardiology (ESC) Heart Failure Congress in Belgrade, Serbia Part B of the TX45 Phase 1b trial initiated in March with topline results expected in the second half of 2025 Ongoing TX45 APEX Phase 2 trial continues to enroll with topline results expected in 2026 Cash and cash equivalents were $306.2 million as of March 31, 2025, including the private placement net proceeds raised in February 2025, expected to provide cash runway into Q4 2028 WATERTOWN, Mass., May 08, 2025 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”), 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 first quarter ended March 31, 2025, and provided an overview of recent business highlights. “During the first quarter, we continued to make meaningful progress across our proprietary pipeline and fortified our cash position with over 3 years of cash runway,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic. “We will be sharing the complete data set from the 19 patients with PH-HFpEF enrolled in Part A of our Phase 1b trial of TX45 at the ESC Heart Failure 2025 Congress. Looking ahead, we expect to present topline results from Part B of the Phase 1b trial in the second half of 2025. We are also advancing our APEX Phase 2 trial and believe the Phase 1b data support both our selected endpoints and patient population, and provided a strong proof-of-principle for the TX45 program.” Recent Business Highlights Positive Interim TX45 Phase 1b Part A Trial Results: In January 2025, Tectonic announced positive interim results from Part A of the TX45 Phase 1b trial in patients with Group 2 pulmonary hypertension in HFpEF (n=16). Results demonstrated that TX45 achieved 17.9% reduction in Pulmonary Capillary Wedge Pressure (“PCWP”) in the total study population of PH-HFpEF and >30% reduction in Pulmonary Vascular Resistance (“PVR”) in Combined pre- and post-capillary PH (“CpcPH”), a subpopulation with more severe disease. Completed Approximately $185.0 Million Private Placement: In February 2025, Tectonic entered into a securities purchase agreement for a private investment in public equity financing (“PIPE”) that resulted in gross proceeds of approximately $185.0 million. Enrollment initiated in Part B of the TX45 Phase 1b Trial: In March 2025, the first patient was enrolled in Part B of the TX45 Phase 1b trial. Part B is evaluating TX45 in patients with Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”). Upcoming Milestones Full Data from Phase 1b Part A Trial to be Presented at the ESC Congress: Full results from the TX45 Phase 1b trial in the Group 2 PH-HFpEF cohort will be presented as an oral late-breaking presentation at the European Society of Cardiology (ESC) Heart Failure 2025 Congress. The data set includes a total of 19 patients with PH-HFpEF. The presentation is scheduled for May 17, 2025, at 10:40 a.m. ET. Ongoing Phase 1b Part B Results Expected 2H 2025: Part B of the TX45 Phase 1b hemodynamic clinical trial evaluating single doses of TX45 in subjects with PH-HFrEF continues to enroll, with topline results expected in the second half of 2025. Ongoing APEX Phase 2 Clinical Trial Results Expected in 2026: The global, 24-week APEX Phase 2 clinical trial, a randomized, placebo-controlled study designed to evaluate the safety and efficacy of TX45 administered subcutaneously in subjects with PH-HFpEF, enriched for CpcPH, continues to enroll, with topline results expected in 2026. Overview of Financial and Operating Results Cash Position: As of March 31, 2025, cash and cash equivalents were $306.2 million, compared to $141.2 million as of December 31, 2024. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents, will provide a cash runway into Q4 2028, including through key Phase 1b and Phase 2 readouts for TX45, and the progression of the hereditary hemorrhagic telangiectasia (“HHT”) program into clinical development. Research and Development Expenses: Research and development expenses were $13.0 million for the three months ended March 31, 2025, as compared to $10.8 million for the three months ended March 31, 2024. The increase was primarily the result of increased CRO and CDMO costs related to the discovery and development of Tectonic’s product candidate TX2100 for the treatment of HHT. General and Administrative Expenses: General and administrative expenses were $5.3 million for the three months ended March 31, 2025, as compared to $2.2 million for the three months ended March 31, 2024. The increase was primarily the result of higher audit, legal and professional services to support operations as a public company. Tectonic also incurred higher employee-related expenses due to an increase in non-cash stock-based compensation during the period. Net Loss: For the three months ended March 31, 2025, the Company had a net loss of $15.9 million compared to a net loss of $15.2 million for the three months ended March 31, 2024. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically Pulmonary Hypertension in Heart Failure with preserved Ejection Fraction (“PH-HFpEF”). In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and Combined pre- and post-capillary PH (“CpcPH”). CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in Pulmonary Vascular Resistance (“PVR”). Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About Tectonic Tectonic Therapeutic is a clinical-stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow us on LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements.” These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 1b and Phase 2 clinical trials for its lead program, TX45, in Group 2 PH-HFpEF; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed with the SEC on May 8, 2025, and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. For more information, please visit www.tectonictx.com and LinkedIn. *Working capital is defined as current assets less current liabilities Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412

TX45 Phase 1b trial interim analysis demonstrated meaningful improvements in both left ventricular function and pulmonary hemodynamics in patients with Group 2 Pulmonary Hypertension in Heart Failure with Preserved Ejection Fraction (“PH-HFpEF”) Positive TX45 Phase 1b interim results support endpoints and patient population in ongoing APEX Phase 2 trial, with topline results expected in 2026 TX45 Phase 1b Part B trial enrolled its first subject with Heart Failure with reduced Ejection Fraction (“HFrEF”) in March 2025 Cash and cash equivalents of $141.2 million as of December 31, 2024 and February 2025 private placement gross proceeds of approximately $185.0 million, together expected to provide a cash runway into Q4’28 WATERTOWN, Mass., March 20, 2025 (GLOBE NEWSWIRE) -- Tectonic Therapeutic, Inc. (NASDAQ: TECX) (“Tectonic”), 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 fourth quarter and full year ended December 31, 2024, and provided an overview of recent business highlights. “2024 was an important year for Tectonic as we transitioned to a public company, and 2025 is already off to an excellent start,” said Alise Reicin, M.D., President and Chief Executive Officer of Tectonic. “We are very pleased to have recently reported positive interim results from our ongoing Phase 1b trial of TX45, which we believe supports the endpoints and patient population included in our ongoing APEX Phase 2 trial. We look forward to presenting detailed results at an upcoming medical meeting as well as continuing to advance both the APEX Phase 2 trial and Part B of the Phase 1b trial.” Recent Business Highlights Positive TX45 Phase 1b Part A Interim Trial Results: In January 2025, Tectonic announced positive interim results from Part A of the Phase 1b trial of TX45 in patients with Group 2 pulmonary hypertension in HFpEF. Results demonstrated that TX45 achieved 17.9% reduction in Pulmonary Capillary Wedge Pressure (“PCWP”) in the total study population of PH-HFpEF and >30% reduction in Pulmonary Vascular Resistance (“PVR”) in Combined pre- and post-capillary PH (“CpcPH”), a subpopulation with more severe disease. In addition, results demonstrated that TX45 achieved 17.4% improvement in Cardiac Output in the total study population of PH-HFpEF. Full results from the Phase 1b Part A trial are planned to be presented at a future medical meeting this year. Completed Approximately $185.0 Million Private Placement: In February 2025, Tectonic entered into a securities purchase agreement for a private investment in public equity financing (“PIPE”) that resulted in gross proceeds of approximately $185.0 million. Hosted Key Opinion Leader (KOL) Webinar: In December 2024, Tectonic hosted a KOL webinar featuring John R. Teerlink, MD, FHFSA (University of California San Francisco) and Raymond L. Benza, MD, FACC, FAHA, FACP (Icahn School of Medicine at Mount Sinai), who discussed the unmet medical need and current treatment landscape for patients with Group 2 PH-HFpEF. A replay of the webinar can be accessed here. Presented Positive TX45 Phase 1a Results at AHA 2024: In November 2024, detailed results from the Phase 1a trial of TX45 was presented in a poster at the American Heart Association (AHA) Scientific Sessions. A copy of the poster presentation can be found here. Upcoming Milestones Phase 1b Part B Results Expected 2H’25: Part B of the TX45 Phase 1b hemodynamic clinical trial evaluating single doses of TX45 in subjects with Pulmonary Hypertension in Heart Failure with reduced Ejection Fraction (“PH-HFrEF”) enrolled its first patient in March, with topline trial results expected in the second half of 2025. Ongoing TX45 APEX Phase 2 Clinical Trial Results Expected in 2026: The global, 24-week APEX Phase 2 clinical trial is a double-blind, randomized, placebo-controlled study designed to evaluate the safety and efficacy of TX45 administered subcutaneously in subjects with PH-HFpEF, with topline trial results expected in 2026. TX2100 GPCR Antagonist for Hereditary Hemorrhagic Telangiectasia (“HHT”) Phase 1 Initiation Expected Q4’25 or Q1’26: TX2100 is a GPCR targeting biotherapeutic being developed as a potential treatment for HHT, the second-most common genetic bleeding disorder. TX2100 remains on track to initiate a Phase 1 clinical trial in Q4’2025 or Q1’2026 following the conclusion of favorable IND enabling studies. A 4-week non-human primate (NHP) dose-range study with a functionally equivalent precursor to TX2100 showed no treatment-related toxicity at doses up to 100 mg/kg. A formulation supporting TX2100 SC dosing has been identified. Both IND enabling NHP GLP toxicology studies and technical development activities to generate GMP drug supply and drug product for TX2100 is expected to start in Q2’2025. Overview of Financial and Operating Results Cash Position: As of December 31, 2024, cash and cash equivalents were $141.2 million, compared to $159.1 million as of September 30, 2024. Tectonic anticipates that, based on current operating assumptions, its current cash and cash equivalents will provide a cash runway into Q4’28, including through key Phase 1b and Phase 2 readouts for TX45, and the progression of the HHT program into clinical development. Research and Development Expenses: Research and development expenses were $9.2 million for the three months ended December 31, 2024, as compared to $7.1 million for the three months ended December 31, 2023. The increase was primarily due to higher contract research organization and contract development manufacturing organization costs related to the progression of the Phase 1b and Phase 2 clinical trials of TX45, and early planning and development manufacturing activity for TX2100, respectively. Tectonic also incurred higher employee-related expenses due to an increase in non-cash stock-based compensation during the period. General and Administrative Expenses: General and administrative expenses were $4.8 million for the three months ended December 31, 2024, as compared to $2.3 million for the three months ended December 31, 2023. The increase was primarily a result of higher audit, legal and professional services to support operations as a public company. Tectonic also incurred higher employee-related expenses due to an increase in non-cash stock-based compensation during the period. Net Loss: For the three months ended December 31, 2024, the Company had a net loss of $12.4 million compared to a net loss of $7.9 million for the three months ended December 31, 2023. About Group 2 Pulmonary Hypertension in HFpEF The World Health Organization has defined 5 groups of pulmonary hypertension (“PH”). Tectonic is focused on the Group 2 subtype, a condition that develops due to left-sided heart disease, specifically PH-HFpEF. In patients with PH-HFpEF, chronic heart failure leads to increased blood pressure in the pulmonary arteries, exerting severe strain on the right side of the heart, which adapts poorly to the increased pressure. This increased pulmonary pressure gradually causes worsening exercise capacity, shortness of breath and right-sided heart failure which can lead to death. PH-HFpEF is further segmented based on pulmonary hemodynamics into Isolated, post-capillary PH (“IpcPH”) and CpcPH. CpcPH is more severe, accounts for about one third to one half of the 1.4 million PH-HFpEF patients in the U.S. and is characterized by additional, abnormal changes to the pulmonary vasculature, leading to an increase in PVR. Although several Group 1 PH (Pulmonary Arterial Hypertension, “PAH”) medications have been explored in Group 2 PH, to date, no medications have been approved for its treatment. About TX45, a long-acting Fc-relaxin fusion protein TX45 is an Fc-relaxin fusion protein with optimized pharmacokinetics and biophysical properties that activates the RXFP1 receptor, the G-protein coupled receptor target of the hormone relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women that is a pulmonary and systemic vasodilator with lusitropic, anti-fibrotic and anti-inflammatory activity. In normal human physiology, relaxin is upregulated during pregnancy where it exerts vasodilative effects, reduces systemic and pulmonary vascular resistance and increases cardiac output to accommodate the increased demand for oxygen and nutrients from the developing fetus. Relaxin also exerts anti-fibrotic effects on pelvic ligaments to facilitate delivery of the baby. About TX2100 TX2100 is a GPCR-targeting biotherapeutic that is being developed to treat HHT, the second most common genetic bleeding disorder. In HHT, loss-of-function mutations in the BMP9/10-Endoglin-ALK1-SMAD4 signaling pathway lead to increased expression of factors that promote abnormal blood vessel formation. The abnormal blood vessel formations found in HHT, also known as telangiectasias and arterio-venous malformations or “AVMs”, are prone to spontaneous recurrent and severe bleeding episodes that can be life-threatening, yet there are no approved therapies to treat these patients. The target GPCR for TX2100 is a receptor for an angiogenic factor known to be upregulated in animal models of HHT. By blocking the signaling of this receptor, Tectonic anticipates it can reduce bleeding resulting from the abnormal blood vessel formation seen in HHT. About Tectonic Tectonic is a clinical stage biotechnology company focused on the discovery and development of therapeutic proteins and antibodies that modulate the activity of GPCRs. 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. Tectonic focuses on areas of significant unmet medical need, often where therapeutic options are poor or nonexistent, as these are areas where new medicines have the potential to improve patient quality of life. Tectonic is headquartered in Watertown, Massachusetts. For more information, please visit www.tectonictx.com and follow on LinkedIn. Forward-Looking Statements This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements in this press release other than statements of historical facts are “forward-looking statements. These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to, statements regarding: the design, objectives, initiation, timing, progress and results of current and future preclinical studies and clinical trials of Tectonic’s product candidates, including the ongoing Phase 1b and Phase 2 clinical trials for its lead program, TX45, in Group 2 PH-HFpEF; the proposed initiation of a Phase 1 clinical trial for its development candidate for a second program in HHT, including its preclinical studies and anticipated endpoints; and the Company’s expected cash runway. These forward-looking statements are based on Tectonic’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Tectonic’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Many factors may cause differences between current expectations and actual results, including: the potential that success in preclinical testing and earlier clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a product candidate; the impacts of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on Tectonic’s business, clinical trials and financial position; unexpected safety or efficacy data observed during preclinical studies or clinical trials; clinical trial site activation or enrollment rates that are lower than expected; Tectonic’s ability to realize the benefits of its collaborations and license agreements; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; and unexpected litigation or other disputes. Other factors that may cause Tectonic’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are identified under the heading “Risk Factors” in Tectonic’s quarterly report on Form 10-Q filed with the SEC on November 7, 2024, and in other filings that Tectonic makes and will make with the SEC in the future. Tectonic expressly disclaims any obligation to update any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise, except as otherwise required by law. For more information, please visit www.tectonictx.com and follow @TectonicTx on X (formerly Twitter) and LinkedIn. CONTACT: Contacts: Investors: Dan Ferry LifeSci Advisors [email protected] (617) 430-7576 Media: Kathryn Morris The Yates Network [email protected] (914) 204-6412