Exhibit 99.1

Tectonic Therapeutic Announces Fourth Quarter and Full Year 2024 Financial Results and Recent Business Highlights

WATERTOWN, MA, 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

Upcoming Milestones

Overview of Financial and Operating Results

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.

Contacts:

Investors:

Dan Ferry

LifeSci Advisors

daniel@lifesciadvisors.com

(617) 430-7576

Media:

Kathryn Morris

The Yates Network

Barbara@theyatesnetwork.com

(914) 204-6412

Tectonic Therapeutic, Inc.

Statements of Operations and Comprehensive Loss

(in thousands, except share and per share data)

Tectonic Therapeutic, Inc.

Select Condensed Consolidated Balance Sheet Data

(in thousands, unaudited)

*Working capital is defined as current assets less current liabilities