TECX Tectonic Therapeutic Inc

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Exhibit 99.1 Innovating GPCR-Targeted Therapies to Reach Large Untapped Market Opportunities JANUARY 2025

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2 DISCLAIMER Statements contained in this presentation regarding matters that are not historical facts are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Words such as anticipates, believes, expects, intends, “plans,” “potential,” projects,” “would” and future or similar expressions are intended to identify forward-looking statements. Each of these forward-looking statements involves substantial risks and uncertainties that could cause actual results to differ significantly from those expressed or implied by such forward- looking statements. Forward-looking statements contained in this presentation 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 our product candidates, including the ongoing Phase 1b and Phase 2 clinical trial for TX45, in Group 2 Pulmonary Hypertension; the expected timing of program updates and data disclosures; the timing of filing INDs and other regulatory documents; the timing and likelihood of seeking regulatory approval for our product candidates including TX45; the competitive landscape for our product candidates; and our ability to identify and develop additional product candidates. These forward-looking statements reflect our current beliefs and expectations. Many factors may cause differences between current expectations and actual results, including the early stage of our development efforts; 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 candidates; clinical site activation rates or clinical trial enrollment rates that are lower than expected; changes in expected or existing competition; changes in the regulatory environment; the uncertainties and timing of the regulatory approval process; the impact of macroeconomic conditions, including the conflict in Ukraine and the conflict in the Middle East, heightened inflation and uncertain credit and financial markets, on our business, clinical trials and financial position; and unexpected litigation or other disputes. These and other risks are described more fully in our filings with the Securities and Exchange Commission (“SEC”), including the risks detailed in our Quarterly Report on Form 10-Q filed with the SEC on November 12, 2024, and other documents we subsequently filed with or furnished to the SEC. All forward-looking statements contained in this presentation speak only as of the date on which they were made. Except as required by law, we assume no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available. This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. Neither we nor any other person makes any representation as to the accuracy or completeness of such data or undertakes any obligation to update such data after the date of this presentation. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

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3 Tectonic Tx: GPCR-Targeted Therapies for High-Value Opportunities TECX focused on discovery & development of GPCR-target biologics with significant unmet need Clinical-Stage Biotech • Founded in 2019 by Tim Springer and Andrew Kruse, TECX went public via reverse merger (AVROBIO) in June 2024 with a concurrent private placement of approximately $131 million Tenured Team Executive team with numerous accomplishments, resulting in 20 “first” approvals TX45 Lead Long-acting relaxin in Phase 2, with de-risking Phase 1b topline results expected in Q1’25 Pipeline Asset • Initial indication targeting Group 2 Pulmonary Hypertension (PH) associated with Heart Failure with Preserved Ejection Fraction (HFpEF), or PH-HFpEF • Positive Phase 1a clinical trial results support best-in-class potential, including favorable safety profile • Potential to target other indications, including other PH groups, heart failure and renal disease Relaxin Potentially Relaxin physiologic and hemodynamic effects demonstrated in prior clinical studies Ideal for PH-HFpEF • Prior clinical development of relaxin by Novartis adds to clinical rationale for TX45 targeting PH-HFpEF * PH-HFpEF Significant >1M+ patients in the U.S. with no approved therapy ; high 5-year mortality Market Potential • Eli Lilly and Astra Zeneca also pursuing relaxin programs targeting heart failure indications and renal disease TX2100 Second Targeting rare bleeding disorder called Hereditary Hemorrhagic Telangiectasia (HHT) Pipeline Asset • Significant market potential, no approved therapies for HHT, estimated ~75K patients in the U.S. alone (15-20% severe) • Phase 1 clinical trial initiation expected in Q4’25 / Q1’26 Near-term Catalyst TX45 Phase 1b, hemodynamic topline results in PH-HFpEF subjects (Part A) expected in Q1’25 • Topline results from Part B of Phase 1b, hemodynamic trial evaluating PH-HFrEF subjects expected in 2H’25 Well-Capitalized ~$159 million in cash as of 9/30/24, expected to provide a cash runway into mid-2027 JANU AR Y 2025 * Estimates based on company sponsored market analysis conducted by Health Advances

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4 This Accomplished Team Has Delivered for Patients and Investors Alise Daniel Peter Anthony Marcella Marc Reicin, M.D. McNamara, Ph.D. Muslin, M.D. Ruddy, M.D. Schwabish, Ph.D. Lochner CEO, Director CSO CDO CMO CBO CFO FOUNDED MULTIPLE GPCR EXPERT, SUCCESSFUL COMPANIES FORBES ”30 under 30” Timothy Andrew LeukoSite Springer, Ph.D. Kruse, Ph.D. Co-Founder Co-Founder Multiple Awards and Fellowships 2022 Lasker Award (Biomedical Research, NIH, Amgen, Sloan Research) JANU AR Y 2025

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5 Biologics Offer Advantages Over Small Molecules in Targeting GPCRs, Hold Potential to Transform Therapeutic Landscape Of the approved drugs that target GPCRs only three are antibodies When difficult to target with small >18%* >470 ~12% molecule, biologic captures complexity remain approved drugs unexploited approved of ligand/receptor engagement (~33% of all) drugs target 100 GPCRs Biologic minimizes off-target binding Non-Sensory to improve safety/tolerability Orphan >$180B GPCRs 800+ In annual sales (~20%) GPCRs Engineer biologic to target or exclude tissue or compartment Predominantly small molecules Sensory GPCRs Bispecific approach enables dual (~50%) target engagement when multi- Address broad modal action is required range of therapeutic areas (*) Hauser, A.S. et al., Cell. 2018 Jan 11; 172(1-2): 41–54.e19. * 18% = 100% - 12% (approved drug targets) – 50% (sensory) – 20% (non-sensory, orphan) JANU AR Y 2025

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6 Our Unique Pipeline Opportunities are Enabled by Biologic Targeting of GPCRs Group 2 Pulmonary Hypertension Long-Acting Relaxin Potential Best-in-Class Profile (PH) due to HFpEF in Phase 2 1 to Target RXFP1 Positive Phase 1a clinical data Hereditary Hemorrhagic 2 GPCR Antagonist Potential First-in-Class Telangiectasia (HHT) (anti-angiogenic) Target pathway linked to disease pathway Fibrosis 2 GPCR Modulator Bispecific Approach Supporting clinical data for one (anti-fibrotic) component of bispecific Scale of proof-of-concept studies: ~50-200 subjects per indication; 3-6 months treatment endpoints 1. Fc-Fusion protein – lead molecule in-licensed from Harvard U., optimized using GEODe platform JANU AR Y 2025 2. GPCR targeted therapeutics discovered internally using GEODe platform

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7 Unique Pipeline of GPCR-Targeted Biologics Underpinned By TX45 Targeting PH-HFpEF with P1b Results Expected Q1’25 PROGRAM / INDICATION DISCOVERY IND ENABLING PHASE 1 PHASE 2 ANTICIPATED MILESTONES • Phase 1b hemodynamic PH-HFpEF GROUP 2 PH-HFpEF results expected in Q1’25, with PH- TX45 Potential Best-in-Class HFrEF results expected in 2H’25 1 RXFP1 Agonist • Phase 2 results expected in 2026 • Phase 1 trial initiation expected in HEREDITARY HEMORRHAGIC Q4’25 / Q1’26 TELANGIECTASIA (HHT) TX2100 Potential First-in-Class & Indication • Phase 2 trial planned late Q4’26 / 2 GPCR Antagonist (anti-angiogenic) early Q1’27 FIBROSIS Bispecific Approach 2 GPCR Modulator (anti-fibrotic) • Bispecific / anti-fibrotic and other GPCR modulators ongoing GPCR MODULATORS 1. Fusion protein – lead molecule in-licensed from Harvard U., optimized using GEODe platform 2. GPCR-targeted biologics discovered internally using GEODe platform JANU AR Y 2025

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8 TX45: Long-acting relaxin to address large, unmet need in Group 2 PH RXFP1 agonist with differentiated profile

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9 TX45 TX45: Potential Best-in-class Treatment for Group 2 PH-HFpEF • Protein engineering has extended pharmacologic half-life to support monthly dosing Relaxin with optimized PK • Rigorous Phase 1 PK/PD model enabled robust Phase 2 dose selection * • Group 2 PH-HFpEF has no approved therapy High unmet need ** • >1M+ patients in US and high 5-year mortality • Pulmonary and systemic vasodilator; improves cardiac relaxation during diastole Mechanism appears ideal to • Reversal of fibrosis in pulmonary vasculature and heart address disease pathology • Anti-inflammatory • Serelaxin demonstrated clinical and hemodynamic benefits in acute heart failure Supporting clinical and pre-clinical data • Clear benefit observed with TX45 in rodent PH and congestive heart failure models • Enrichment strategy for CpcPH patients where there is the greatest unmet need Streamlined and differentiated • No outcome study needed clinical strategy • Enables potential early launch relative to broad heart failure indication Potential to expand market • Other PH Groups, heart failure, renal disease * Heart Failure with preserved Ejection Fraction, ** US prevalence numbers for Class 2 and 3, estimates based on company sponsored market analysis conducted by Health Advances

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10 TX45 Significant Pharma Interest in Relaxin Tectonic has potential best-in-class molecule Half Life Patient Phase 2 Company Format Formulation Dosing* in NHV Population Endpoints Group 2 PH / Change in pulmonary Fc-Fusion Sub Q 14-20 days Q4 Weeks HFpEF (enriched vascular resistance (TX45) for CpcPH) (PVR) Change in pulmonary Fc-Fusion Group 2 PH / Sub Q 7-9 days** Q2 Weeks* vascular resistance (AZD3427) HFpEF and HFrEF (PVR) Change in Small Molecule PO 3-6 hours QD* CHF echocardiography (AZD5462) parameters h-Albumin-mAb- Sub Q Change in left atrial Fusion 8-10 days Q Weekly* HFpEF Injection site reservoir strain (LARS) reactions (LY3540378) * Expected dosing frequency, AZN and LLY based on dosing frequency in Phase 2 studies listed in clinical trials database ** Half life of 13-14 days reported in patients with CHF based on sparse PK profiling JANU AR Y 2025

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11 TX45 Hemodynamic and Anti-fibrotic Properties of Relaxin Demonstrated by its Role in Pregnancy Pharmacology Facilitates Gestation AGONIST PULMONARY AND Natural Ligand of SYSTEMIC VASODILATOR RXFP1 Receptor Increases cardiac output to accommodate the Relaxin-2 increased demand from No RXFP1 developing fetus internalization from relaxin agonism → no desensitization with ANTIFIBROTIC chronic therapy Prepares musculoskeletal Relaxin upregulated in tissues for pregnancy pregnancy and childbirth RXFP1 active state JANU AR Y 2025

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12 TX45 The First Recombinant Relaxin (Serelaxin) Demonstrated Safety and Benefit in Acute Heart Failure (AHF) in Trials of >11,000 Patients Background • Program sponsored by Novartis META ANALYSIS: Serelaxin was Efficacious in AHF • Serelaxin half life <9 hours, a major hurdle for development for chronic disease Study Relative Risk N N • 2–day continuous IV dosing in patients with acute heart failure (WHF Day 5) [95% CI] (Drug) (PBO) 0.77 [0.67 – 0.89] Results and Insights Meta Analysis 6,090* 5,239 p = 0.0002 • Serelaxin demonstrated safety in greater than 6,000 patients Pre-RELAX AHF 0.56 [0.22 – 1.45] 42 61 • Meta-analysis showed significant benefit • Development halted after pivotal study, AHF-2, failed to RELAX-AHF 0.54 [0.37 – 0.78] 581 580 achieve co-primary endpoints ‒ Trial design and operational challenges may have contributed * RELAX-AHF-2 0.90 [0.76 – 1.07] 3,274 3,271 to failure ‒ More recently, Biomarker sub-study (N=1020) accepted Nov. 12, 2024 RELAX-AHF-EU 0.71 [0.52 – 0.98] 1,756 894 showed 45% improvement in 5-day worsening heart failure (p= 0.025) and biomarker changes, including reduction in NT-proBNP and 1 RELAX-AHF-ASIA 0.42 [0.21 – 0.84] 437 433 Troponin replicated prior studies • RXFP1 agonism is beneficial in cardiovascular disease • A long-acting relaxin in the ideal indication could benefit patients 1. A.A. Voors et al., European Journal of Heart Failure 2024 JANU AR Y 2025 * Teerlink J.R. et al. Eur. J. Heart Fail. 2019; 22: 315-329; patients from RELAX-AHF-JP (N=30 total) not listed in table

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13 TX45 TX45 is Engineered to Solve a Critical PK Problem Observed With Other Relaxin Molecules TX45 Exhibits Superior Profile vs. Parent Compound 2,3 and Comparator Molecules Preclinical Rat Pharmacokinetic Data Relaxin has very short in vivo half-life Fc-fusion needed to improve PK Half-life extended relaxins have steep decline pI <9, TX-45 in exposure after dosing (>90%) because of 1 glycocalyx binding due to high pI pI >9, Comparator pI >9, TX early Engineering TX45 to reduce net positive charge (and lower pI) prevents rapid clearance 1. Isoelectric Point 2. High pI Fc-relaxin fusion protein described in literature 3. Source: Tectonic internal data JANU AR Y 2025 Concentration

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14 TX45 TX45 Initial Indication: Group 2 Pulmonary Hypertension (PH) Pulmonary hypertension consists of 5 distinct diseases, or groups • Idiopathic, hereditary or drug-induced Group 1 • Connective tissue disease-associated PAH Group 2 PH is chronic, progressive • Congenital heart disease-associated and the largest category of * Pulmonary Hypertension • Due to left heart failure (HFpEF, HFrEF ) or valvular heart disease Group 2 ** • CAD, HTN, T2DM , high cholesterol are risk factors PH • Elevated blood pressure in the • Two Subtypes: CpcPH & IpcPH pulmonary arteries • Due to lung disease or hypoxia • Chronically elevated pulmonary • May be due to COPD, interstitial lung disease (i.e., IPF) or Group 3 arterial pressures taxes the right side obstructive sleep apnea of the heart • Pulmonary artery narrowing and Group 4 • Chronic thrombo-embolic pulmonary hypertension – i.e., as a muscularization consequence of blood clots CTEPH • Over time, the disease can lead to right heart failure and death Group 5 • Miscellaneous group including sickle cell, polycythemia vera, • No approved therapies and sarcoidosis Misc. * Heart Failure with reduced Ejection Fraction JANU AR Y 2025 ** CAD: Coronary Artery Disease, HTN: Hypertension, T2DM: Type 2 Diabetes Mellitus

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15 TX45 Initial Focus on Group 2 PH due to Heart Failure With Preserved EF (HFpEF), Enriched for CpcPH Patients Clinical program designed to enable evaluation of efficacy in overall population and CpcPH IpcPH (Isolated, post capillary PH) Heart Increased Left Ventricle Filling Pressures HFpEF Normal Ô HFpEF 1 Increased Pulmonary Venous Pressures (~4M) Ô Passive Pressure Backflow Ô Pulmonary Hypertension Group 2 PH 1 (~1.4M) IpcPH CpcPH (Combined, pre- and post capillary PH) 2 CpcPH (~1M) (~400K) Chronic PH and/or Other Drivers Pulmonary Vasculature Ô Permanent Vascular Changes, e.g. Pulmonary Artery Remodeling Ô Increased Vascular Resistance Ô Normal PAH-like Right Heart Failure 1. US prevalence numbers for Class 2 and 3, estimates based on company sponsored market analysis conducted by Health Advances JANU AR Y 2025 2. Assumes diagnosis based on pulmonary vascular resistance (PVR) of > or equal to 3 wood units

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16 TX45 Group 2 PH vs. PAH (Group 1) Significant opportunity for a first-in-indication therapy Highly motivated physicians and patients No Therapeutic Options 4 US Prevalence >> PAH 5-Year Survival ≤ PAH For Group 2 PH 1 ~1,400,000 Group 2 PH PAH ~ 50% 50% No approved Multiple drugs/ IpcPH therapies mechanisms (~1M) approved … 23% Limited pipeline ET1R antagonists PDE5 inhibitors PAH Drugs have GC stimulators CpcPH not demonstrated Prostaglandins (~400K) 2 convincing ACTRII-Trap >25,000 efficacy in Group 2 PH with cpcPH IpcPH PAH Group 2 PH PAH the exception of PDE5i in CpcPH Multi-$ Billion Market >$4 Billion Market in Group 2 PH 3 Opportunity US Today 1. US prevalence numbers for Class 2 and 3, estimates based on company sponsored market analysis conducted by Health Advances 2. www.pahinitiative.com 3. GlobalData 4. Caravita S. et al. https://doi.org/10.1371/journal.pone.0199164; Gall H. et al The Journal of Heart and Lung Transplantation, Vol 36, No 9, September 2017; estimates from synthesis of different studies JANU AR Y 2025

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17 TX45 Relaxin Agonism of RXFP1 Elicits Changes in Multiple Organs and Organ Systems Important in PH-HFpEF “ Vasodilation ” RV / LV* Pulmonary & Systemic Afterload “ NO ” Endothelin-1 Relaxin “ LV Relaxation Improved LV agonist Diastolic Function “ SERCA2 function ” Fibrosis RV / LV and Pulmonary Artery Anti-Inflammatory “ MMPs ” TGFβ Reverse Remodeling RXFP1 + “ Na Excretion “ Renal Blood Flow ” RV / LV Preload * RV: right ventricle; LV: left ventricle JANU AR Y 2025

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18 TX45 Relaxation and Anti-Fibrotic Effects of Relaxin Have Potential for Disease Modification in PH-HFpEF • Heart and vascular dysfunction contribute to disease pathology • Renal dysfunction also present in many of these patients CHARACTERISTICS OF PH-HFpEF ANTICIPATED RELAXIN EFFECTS Pulmonary Vasodilation Pulmonary artery narrowing, thickening, stiffening, fibrotic remodeling Anti-inflammatory, anti-fibrotic Peripheral vasodilation, improved Thickening and stiffening of Left Ventricle cardiac relaxation, left ventricular remodeling Compromised kidney function Improvement in kidney function, natriuresis Combined decrease in pulmonary pressure and increased cardiac function are expected to be needed for efficacy in PH-HFpEF JANU AR Y 2025

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19 TX45 In Acute Heart Failure (AHF), Serelaxin Improves LV Function (Lowering 1 PCWP), and Lowers Pulmonary Pressures and Resistance (mPAP, PVR) Furosemide given 4h prior to serelaxin infusion, and 8h after initiation of serelaxin PCWP mPAP PVR Lung capillary pressure – Pulmonary (lung) Blood flow resistance in measure of left atrial pressure artery pressure pulmonary arteries Hours post dose Hours post dose Hours post dose In a similar study in patients with chronic heart failure, 2 a reduction in PCWP and an increase in cardiac output was demonstrated 1. Ponikowski P. et al. Eur. Heart J. 2014 2. Dschietzig T. et. Al. Ann NY Acad Sci 2009 JANU AR Y 2025 PCWP (mmHg) mPAP (mmHg) 5 PVR (dyn*s/cm )

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20 TX45 TX45 Development Program Overview 2026 2024 2025 Healthy Phase 1a Toplined Sept ’24 Volunteers Safety, PK, PD (Renal Blood Flow) Safety, tolerability, PK/PD Group 2 PH Phase 1b with HFpEF RHC study to establish hemodynamic proof of concept Group 2 PH - Part A (PH-HFpEF); Part B (PH-HFrEF) with HFrEF Group 2 PH with HFpEF Phase 2 (enriched for CpcPH) Randomized, 6-month study RHC: Right Heart Catheter mPAP: Mean Pulmonary Arterial Pressure Development Plan Reviewed with FDA via Pre IND PVR: Pulmonary Vascular Resistance CO: Cardiac Output 6MTD: 6-Minute Walk Distance JANU AR Y 2025

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21 TX45 Phase 1a Clinical Study Complete Positive results support on-going development Robust Design of TX45 SAD Study Benefits of the Study Design • Exposure-response model developed with over 200 data points • Overcomes impact of outlier values on mean values based on 6 patients per dose cohort • Enables more robust dataset with which to choose doses for Phase 2 JANU AR Y 2025

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22 TX45 TX45 Shows Favorable Safety Profile • No discontinuations or treatment-related SAEs • No observed injection site reactions, immunogenicity, or detection of anti-drug antibodies • Most common AE was transient orthostatic tachycardia (increases in heart rate with standing) ‒ Placebo: 17% vs TX45: 23% ‒ Not associated with drops in blood pressure • No clinically meaningful changes in vital signs or labs JANU AR Y 2025

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23 TX45 TX45 Single Dose Demonstrates Extended Half-Life in Subjects TX45 Pharmacokinetics (PK) Profile Single Dose TX45 Pharmacokinetics • Potential best-in-class terminal elimination half life of 14-20 days • PK was dose proportional with subcutaneous bioavailability of ~50% • Modeled accumulation at steady state after multiple doses is predicted to be 1.5X for 300 mg SC every 4 weeks (Q4W) and 2X for 300 mg SC every 2 weeks (Q2W) JANU AR Y 2025

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24 TX45 Preclinical PK/PD from Acute Renal Blood Flow (RBF) Model Informs Target Plasma Concentration Levels at Trough for Maximum Therapeutic Effect RBF Model • Used to assess pharmacodynamic response to TX45 administration based on acute vasodilatory effects of relaxin, as measured by increased rat renal blood flow (RBF) MCT Model • Used to assess the therapeutic anti- inflammatory/anti-proliferative efficacy of TX45 in a rat model of pulmonary hypertension • The trough levels required for maximal efficacy in the MCT model fall provide ~ EC response 70 in the RBF model and predict a trough exposure of 2 ug/ml in humans * * The exposure necessary for human EC70 is predicted to be 2ug i.e. 3-fold lower than in rats given the 3x greater potency of TX45 on human RXFP1 compared to rat RXFP1 JANU AR Y 2025

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25 TX45 Robust Human-Exposure Model Allows for Phase 2 Dose Selection Phase 1a Renal Plasma Flow (RPF) TX45-RPF E model max • Mean dose cohort effects (n=6 per cohort) demonstrated increased renal plasma flow of up to 42% • Incorporation of all exposure-response data across all doses and time points post dose resulted in a modeled Emax = 33% (SE 3.3%, p-value < 0.0001) Phase 2 Dose Selection • 300 mg SC monthly: Steady state trough of 2.6 ug/ml (EC80) slightly higher than preclinical predicted exposures associated with maximal efficacy – Preclinical studies predicted 2 ug/ml at trough would result in maximal efficacy • 300 mg SC every 2 weeks: Steady state trough of 8.7 ug/ml (>EC90), to evaluate whether increased exposure translates to greater efficacy JANU AR Y 2025

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26 TX45 TX45 Development Program Overview Planned readouts in 2025 and 2026 2024 2026 2025 Healthy Phase 1a Volunteers Safety, tolerability, PK/PD Expected Q1’25 (Part A) Group 2 PH PCWP, PVR in CpcPH, exploring TPR + Phase 1b with HFpEF additional HD endpoints RHC study to establish hemodynamic proof of concept Group 2 PH Expected 2H’25 (Part B) - Includes Part A (PH-HFpEF) & Part B (PH-HFrEF) with HFrEF Group 2 PH with HFpEF Phase 2 Expected 2026 PVR, PCWP, 6MWD (enriched for CpcPH) Randomized, 6-month study RHC: Right Heart Catheter mPAP: Mean Pulmonary Arterial Pressure Development Plan Reviewed with FDA via Pre IND PVR: Pulmonary Vascular Resistance CO: Cardiac Output 6MTD: 6-Minute Walk Distance JANU AR Y 2025

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27 TX45 TX45 Phase 1b Trial Design (Part A) Open label single dose safety and hemodynamics trial in PH-HFpEF Study Goals: • Primary Endpoint: Safety and Tolerability • Establish single dose safety in patients • Demonstrate relevant acute hemodynamic • Key Secondary Endpoints: PCWP in all changes consistent with improvement in both LV patient and PVR in CpcPH subgroup function as well as pulmonary vascular dysfunction TX45 IV Ascending Dose Cohort A 0.3 mg/kg Monitor RHC Follow up Baseline Hemodynamics visits Cohort B 1 mg/kg Hemodynamics 8h Days 2, 15, 29 Day 1 Day 1 Cohort C 3 mg/kg New Part B added, evaluating PH-HFrEF subjects, initiating in Q1’25 (3mg/kg dose); data expected 2H’25 JANU AR Y 2025

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28 TX45 Positive TX45 Phase 1b Trial Expected to Improve Probability of Success of TX45 in Later Stage Development GOAL: Treatment for PH-HFpEF needs to both increase LV function and improve pulmonary vascular component of the disease • Decrease (~15-20%) in pulmonary capillary wedge pressure (PCWP) in overall patient population ‒ PCWP provides insight into left ventricular function and correlates with exercise 1 capacity in HFpEF and HFrEF • Decrease (~15-20%) in pulmonary vascular resistance (PVR) in patients with CpcPH ‒ PVR is normal in IpcPH, so a floor effect is likely in this subgroup 2 ‒ In PAH, a lowering of PVR is associated with improvement in 6MWD • Reduction in total pulmonary resistance (TPR) in overall patient population 1. Wolsk E et al. Eur. J. Heart Fail. 2018 2. www.accessdata.fda.gov/drugsatfda_docs/nda/2017/209279Orig1s000MedR.pdf JANU AR Y 2025

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29 TX45 APEX Phase 2 Efficacy Trial Design for TX45 Clinical trial in subjects with PH-HFpEF enriched for subjects with CpcPH subgroup • Global multicenter, double-blind, randomized, placebo-controlled proof-of-concept clinical trial to evaluate the efficacy of TX45 Double-blind Sub Q 24 Week Treatment Period TX45 300mg Q2W (n=60) End of Study End Treatment Randomization RHC Baseline TX45 300mg Q4W (n=60) Week 30 Hemodynamics Hemodynamics Day 1 Week 24 Day -21 to -7 Placebo (n=60) • Primary Endpoint: Change from baseline in PVR • Secondary Endpoints: Change from baseline in PCWP, 6MWD, KCCQ* * Kansas City cardiomyopathy questionnaire JANU AR Y 2025

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30 HHT program Potential first-in-class and indication nd opportunity for 2 most common genetic bleeding disorder

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31 HHT Hereditary Hemorrhagic Telangiectasia (HHT) Autosomal dominant disease that causes abnormal blood vessel formation • Rare, autosomal dominant disease: ~ 75,000 patients in US No currently ‒ Mutations in the BMP9/10 pathway approved AVMs Telangiectasias therapies for HHT • High degree of phenotypic variability (15-20% severe) • Increased mortality risk Nosebleeds Telangiectasias Lung Liver GI tract Brain • Iron and transfusion dependent anemia (10-30% of patients) >95% Nose (epistaxis) • High output CHF 2nd to Liver AVM → liver transplant >90% Skin (telangiectasia) • Stroke FREQUENCY INCREASED 50% Lungs (pulmonary AVMs*) • Brain abscesses and other deep tissue abscesses OF ABNORMAL FREQUENCY OF 50% Liver (hepatic AVMs) HHT VESSELS THE FOLLOWING • Venous thromboembolism (VTE) 20% Gastrointestinal tract • Pulmonary Hypertension 10% Brain (cerebral AVMs) • Migraines JANU AR Y 2025 *AVM= arterial venous malformation

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32 HHT Anti-VEGF: Mouse HHT Model Predictive of Efficacy in Patients Anti-VEGF mAb suppresses AVM formation, Anti-VEGF therapy reduces epistaxis severity, visceral hemorrhage in HHT model improves hem. Parameters in patients ALK-1 Conditional Knock-Out Wound-induced vascular response Decreases Improves Vessel Growth Hemoglobin Levels Incisional wounds • No rigorous clinical studies ever conducted – only evidence is from IITs – Patent expiration on anti-VEGF mab lowered incentive to investment in label expansion – Dose and Dosing interval not well explored Anti-VEGF ab Anti-VEGF ab • Treating physicians concerned about side effects Angiogenesis. 2014 Oct; 17(4): 823–830 Haematologica. 2021 Aug 1; 106(8): 2161–2169 JANU AR Y 2025

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33 HHT A GPCR3 Antagonist Significantly Reduces AVM Formation and Bleeding in Animal Model of HHT Effects of anti-GPCR3 antagonist mAb in mouse HHT model generated by immuno-blocking 1,2 of BMP9 and BMP10 Hemoglobin Levels AVM Formation Retinal Bleeding n=14 1. Ruiz, S. et. al., Scientific Reports, 2016; 6:37366, doi: 10.1038/srep37366 2. Ruiz, S. et. al., J. Clin. Invest., 2020; 130(2):942–957, doi.org/10.1172/JCI127425 Angiogenesis. 2014 Oct; 17(4): 823–830 Haematologica. 2021 Aug 1; 106(8): 2161–2169 JANU AR Y 2025

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34 HHT Projected HHT Development Program Overview 2024 2025 2026 2027 Finalize IND Enabling DC selected Development Studies and CMC November ’24 Candidate (DC) Safety and Tolerability Phase 1a PHASE 1a Initiation Planned Q4’25/Q1’26 Randomized 3-Month Study Patients Hematocrit, Epistaxis Score PHASE 2 with HHT Blood Transfusions Planned late 2026/early 2027 JANU AR Y 2025

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35 Platform Proprietary, validated platform enables reproducible discovery and optimization of GPCR targeted biologics

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36 GEODe Solving Key Challenges in GPCR Targeted Biologics Discovery GEODe Platform Features Challenges Designed for Success RETAIN 1. endogenous GPCR structure to enable Receptor Engineering, and Purification Technology screening against relevant form of receptor Delivers abundant receptor reagent in native conformation PURIFY target in sufficient quantities to power 2. screening campaign In-vitro Yeast Display Antibody Discovery Optimized high-diversity Fab and VHH libraries INDUCE Selection protocols optimized for membrane embedded GPCRs immune response to human GPCR in animals if immunization strategy is pursued 3. STABILIZE Protein Engineering receptor in active conformation to enable Optimize protein pharmacology Engineer antigen formats to enable screening for agonists or agonist discovery antagonists as needed JANU AR Y 2025

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37 Tectonic Tx: Positioned to Deliver on Value-Creating Milestones Two pipeline candidates addressing untapped markets with significant market potential • Lead candidate, TX45, long-acting relaxin in Phase 2, with de-risking Phase 1b trial results expected in Q1’25 • TX45 has best-in-class potential for >1M+ patients with Group 2 Pulmonary Hypertension with HFpEF; potential to expand to other indications in heart failure and renal disease • Second pipeline candidate for HHT, a rare bleeding disorder with no approved therapy Steady cadence of inflection points for 2025 and 2026 • Q1’25: TX45 Phase 1b, hemodynamic topline results in PH-HFpEF subjects (Part A) • 2H’25: TX45 Phase 1b, hemodynamic topline results in PH-HFrEF subjects (Part B) • 2026: TX45 Phase 2 topline trial results; HHT Phase 2 initiation late Q4’26 / early Q1’27 Proven leadership team well-positioned to execute with strong balance sheet • Executive team with proven track record • ~$159 million in cash as of 9/30/24, expected to provide a cash runway into mid-2027 JANU AR Y 2025

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38 Thank You info@tectonictx.com www.tectonictx.com LinkedIn: TectonicTx

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39 TX45 Results of Serelaxin Pre-specified Substudy of RELAX-AHF-2 Demonstrated Multi-Organ Protection Background • In RELAX-AHF-2, no benefit shown on 5-day heart failure worsening or 180d mortality with 48h IV serelaxin treatment • Recent prospective, pre-specified substudy of RELAX- AHF-2 of 1,020 patients (503 randomly assigned to placebo, 517 to serelaxin) assessed changes in biomarkers of cardiac, renal and hepatic damage Results • Serelaxin treatment led to significant Improvement in cardiac and renal injury biomarkers, including NT- proBNP, Troponin T, cystatin C, creatinine and uric acid • In this sub-group, serelaxin treatment associated with 45% reduction in 5d heart failure worsening (p = 0.025), but no change in 180d mortality • Improvement in biomarkers correlated with 180d survival Eur J Heart Fail. 2024 Dec 12. doi: 10.1002/ejhf.3551. JANU AR Y 2025

v3.24.4

Document and Entity Information	Jan. 13, 2025
Cover [Abstract]
Amendment Flag	false
Entity Central Index Key	0001681087
Document Type	8-K
Document Period End Date	Jan. 13, 2025
Entity Registrant Name	Tectonic Therapeutic, Inc.
Entity Incorporation State Country Code	DE
Entity File Number	001-38537
Entity Tax Identification Number	81-0710585
Entity Address, Address Line One	490 Arsenal Way
Entity Address, Address Line Two	Suite 210
Entity Address, City or Town	Watertown
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02472
City Area Code	(339)
Local Phone Number	666-3320
Written Communications	false
Soliciting Material	false
Pre Commencement Tender Offer	false
Pre Commencement Issuer Tender Offer	false
Security 12b Title	Common Stock, $0.0001 par value per share
Trading Symbol	TECX
Security Exchange Name	NASDAQ
Entity Emerging Growth Company	false

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