Filed Pursuant to Rule 424(b)(3)
Registration No. 333-280909

PROSPECTUS SUPPLEMENT

(To the Prospectus dated July 30, 2024)

Up to 2,969,583 Shares of Common Stock

This prospectus supplement supplements the prospectus, dated July 30, 2024 (the “Prospectus”), which forms a part of our registration statement on Form S-1 (No. 333-280909). This prospectus supplement is being filed to update and supplement the information in the Prospectus with certain information contained in our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 14, 2024 (the “Quarterly Report”). Accordingly, we have attached the Quarterly Report to this prospectus supplement.

The Prospectus and this prospectus supplement relate to the proposed offer and resale or other disposition from time to time by the selling stockholders identified in the Prospectus of up to an aggregate of 2,969,583 shares of common stock, par value $0.0001 per share (“Common Stock”), of Tectonic Therapeutic, Inc.

Our Common Stock is listed on the Nasdaq Global Market under the ticker symbol “TECX.” On August 13, 2024, the last reported sales price of our Common Stock was $16.22 per share.

This prospectus supplement should be read in conjunction with the Prospectus, including any amendments or supplements thereto, which is to be delivered with this prospectus supplement. This prospectus supplement is qualified by reference to the Prospectus, including any amendments or supplements thereto, except to the extent that the information in this prospectus supplement updates and supersedes the information contained therein.

This prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the Prospectus, including any amendments or supplements thereto.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described in the section titled “Risk Factors” beginning on page 9 of the Prospectus and under similar headings in any amendments or supplements to the Prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the accuracy or adequacy of this prospectus supplement or the Prospectus. Any representation to the contrary is a criminal offense.

Prospectus Supplement dated August 14, 2024

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)

For the quarterly period ended June 30, 2024

OR

For the transition period from ______________ to ______________

Commission File Number: 001-38537

TECTONIC THERAPEUTIC, INC.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (339) 666-3320

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of August 9, 2024, the registrant had 14,734,479 shares of common stock, $0.0001 par value per share, outstanding.

Table of Contents

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains statements that are not historical facts and are considered forward-looking within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Our forward-looking statements include, but are not limited to, statements regarding our or our management team’s expectations, hopes, beliefs, intentions or strategies, our ability to fund our working capital requirements, our financial performance and our ability to effectively manage our anticipated growth, our ability to obtain additional funding for our operations, and other risks and uncertainties, including those listed under the section titled “Risk Factors” in this Quarterly Report regarding the future. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including, any underlying assumptions, are forward-looking statements. The words “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “will,” “would” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Forward looking statements in this Quarterly Report on Form 10-Q (“Quarterly Report”) may include, for example, statements about:

These forward-looking statements are based on our management’s current expectations, estimates, forecasts and projections about our business and the industry in which we operate, and management’s beliefs and assumptions and are not guarantees of future performance or development. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those described under the section titled “Risk Factors” under Part II, Item 1A below, and under similar captions in our periodic reports filed with the SEC from time to time. Moreover, we operate in a very competitive and rapidly changing environment, and new risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties and assumptions, the forward-looking events and circumstances discussed in this Quarterly Report may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based on information available to us as of the date of this Quarterly Report. While we believe that information provides a reasonable basis for these statements, that information may be limited or incomplete. Our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all relevant information.

You should not rely upon forward-looking statements as predictions of future events. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance, or events and circumstances reflected in the forward-looking statements will be achieved or occur. We undertake no obligation to update publicly any forward-looking statements for any reason after the date of this Quarterly Report to conform these statements to new information, actual results or changes in our expectations, except as required by law.

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements.

TECTONIC THERAPEUTIC, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)

(unaudited)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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TECTONIC THERAPEUTIC, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands, except share and per share amounts)

(unaudited)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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TECTONIC THERAPEUTIC, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY

(DEFICIT)

(In thousands, except share and per share amounts)

(unaudited)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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TECTONIC THERAPEUTIC, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

(unaudited)

The accompanying notes are an integral part of these unaudited condensed consolidated financial statements.

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TECTONIC THERAPEUTIC, INC.

NOTES TO UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Business

Tectonic Therapeutic, Inc. (formerly AVROBIO, Inc.) (the “Company” or “Tectonic”) is 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”). The Company 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. The Company’s corporate headquarters are in Watertown, Massachusetts.

Reverse Merger and Pre-Merger Financing Transaction

On June 20, 2024, the Company completed its previously announced merger transaction in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated as of January 30, 2024 (the “Merger Agreement”) with AVROBIO, Inc. (“AVROBIO”), pursuant to which Alpine Merger Subsidiary, Inc., a wholly owned subsidiary of AVROBIO, merged with and into the entity formerly known as Tectonic Therapeutic, Inc., now known as Tectonic Operating Company, Inc. (“Legacy Tectonic”), with Legacy Tectonic continuing as a wholly owned subsidiary of the surviving corporation of AVROBIO (the “Merger”). The Merger is being accounted for as a reverse recapitalization in accordance with generally accepted accounting principles in the United States of America (“GAAP”), with AVROBIO treated as the acquired company for financial reporting purposes, and Legacy Tectonic treated as the accounting acquirer.

Upon the closing of the Merger, each outstanding share of Legacy Tectonic’s common stock, including outstanding and unvested restricted stock, was converted into the right to receive a number of shares of AVROBIO’s common stock based on an exchange ratio of 0.53 (the “Exchange Ratio”), as defined in the Merger Agreement, after giving effect to the 1-for-12 reverse stock split of AVROBIO common stock that was effected on June 20, 2024. The exchange ratio was retroactively applied to all outstanding common shares, convertible preferred shares, stock options and restricted stock.

Each outstanding and unexercised option to purchase shares of Legacy Tectonic’s common stock immediately prior to closing was assumed by AVROBIO and was converted into an option to purchase shares of AVROBIO common stock, with necessary adjustments to the number of shares and exercise price to reflect the Exchange Ratio. All of Legacy Tectonic’s restricted common stock outstanding and unvested immediately prior to the closing that was assumed by AVROBIO in the Merger remains unvested to the same extent and is subject to the same repurchase option, risk of forfeiture or other condition under any applicable restricted stock purchase agreement.

Legacy Tectonic stockholders received approximately 10,956,614 shares of AVROBIO common stock in connection with the Merger, including 6,901 shares of AVROBIO common stock subject to vesting terms, based on the number of shares of Legacy Tectonic common stock outstanding immediately prior to the Merger, including restricted stock, the number of shares of common stock issued to investors participating in the Subscription Agreements (as defined below) and SAFEs, and Legacy Tectonic convertible preferred stock outstanding immediately prior to the Merger, which was converted into shares of Legacy Tectonic common stock on a one-for-one basis immediately prior to the closing of the Merger.

In connection with the Merger, the Company and its designated rights agent entered into a contingent value rights agreement (the “CVR Agreement”). Pursuant to the CVR Agreement, each holder of AVROBIO common stock immediately prior to the closing received a contractual contingent value right (“CVR”) subject to and in accordance with the terms and conditions of the CVR Agreement, representing the contractual right to receive a pro rata portion of any net proceeds, if any, as a resulting from a disposition of certain AVROBIO intellectual property (including a license of AVROBIO’s pre-closing assets as defined in the CVR Agreement) after the closing and prior to the 18-month anniversary of the closing, received within a 10-year period following the closing; provided that no contingent payment will be payable to any holder of the CVRs until such time as the then-outstanding and undistributed proceeds exceeds $0.4 million in the aggregate. As of June 30, 2024, no proceeds have been received under the CVR Agreement. As of June 30, 2024 there is no liability recorded in connection with the CVR Agreement.

Concurrently with the closing of the Merger, certain investors of Legacy Tectonic completed the purchase of 7,790,889 shares of Legacy Tectonic common stock pursuant to that certain Subscription Agreement dated January 30, 2024 (the “Subscription Agreement”) at a purchase price of approximately $12.40 per share for an aggregate purchase price of approximately $96.6 million. Shares of Legacy Tectonic common stock issued pursuant to the Subscription Agreements were converted into 4,163,606 shares of AVROBIO common stock at the closing of the Merger based on the Exchange Ratio, pursuant to the Merger Agreement.

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Risks and Uncertainties

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. Product candidates currently under development will require significant additional research and development efforts, including extensive pre-clinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure, and extensive compliance reporting capabilities.

The Company’s proprietary GEODe^™ platform is currently in development. There can be no assurance that current and future research and development activities will be successfully completed, that adequate protection for owned intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies.

Liquidity and Going Concern

As of June 30, 2024, the Company had an accumulated deficit of $118.5 million and has incurred losses and negative cash flows from operations since inception, including a net loss of $12.7 million and $27.9 million for the three and six months ended June 30, 2024, respectively. To date, the Company has financed its operations primarily through the issuance of common stock, convertible preferred stock, convertible promissory notes and Simple Agreements for Future Equity (“SAFEs”). The Company has devoted substantially all of its financial resources and efforts to business planning, conducting research and development, recruiting management and technical staff, and raising capital. Management expects that the Company’s operating losses and negative cash flows will continue for the foreseeable future as it continues to develop its product candidates.

As the Company continues to develop its proprietary platform and potential product candidates, it will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. It may never achieve profitability, and unless and until it does, it will continue to need to raise additional capital to fund its operations. Management believes that its current cash on hand, which includes the proceeds related to the Merger and Subscription Agreements, is sufficient to fund the Company’s planned operations for at least one year from the date of issuance of these unaudited condensed consolidated financial statements.

During the six months ended June 30, 2024, there were no significant changes to the Company’s significant accounting policies as described in the Company’s audited consolidated financial statements as of and for the years ended December 31, 2023 and 2022.

Basis of Presentation

The accompanying unaudited interim condensed consolidated financial statements have been prepared in conformity with GAAP and the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to GAAP, as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). In the opinion of the Company, the accompanying unaudited condensed consolidated financial statements contain all adjustments, consisting of only normal recurring adjustments, necessary for a fair presentation of its financial position and its results of operations, changes in convertible preferred stock and stockholders’ equity (deficit) and cash flows. The information as of December 31, 2023 included in the unaudited interim condensed consolidated balance sheets was derived from audited annual consolidated financial statements but does not contain all of the footnote disclosures from the audited annual consolidated financial statements.

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These unaudited interim condensed consolidated financial statements should be read in conjunction with the audited annual consolidated financial statements as of and for the years ended December 31, 2023 and 2022.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of expenses during the reporting periods. Significant items subject to such estimates and assumptions include the contract research accruals, stock-based compensation expense, the fair value of the Company’s common stock, the income tax valuation allowance, and the fair value determination of the SAFEs. Management’s estimates are based on historical experience and various other assumptions that it believes are reasonable under the circumstances. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.

Principles of Consolidation

The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB, or other standard setting bodies and are adopted by the Company as of the specified effective dates. Unless otherwise discussed, the impact of recently issued standards that are not yet effective are not anticipated to have a material impact on the Company’s condensed consolidated financial statements upon adoption.

Recently Issued Accounting Pronouncements Not Yet Adopted

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280) (“ASU 2023-07”), which enhances the segment disclosure requirements for public entities on an annual and interim basis. Under ASU 2023-07, public entities will be required to disclose significant segment expenses that are regularly provided to the chief operating decision maker (“CODM”) and included within each reported measure of segment profit or loss. Additionally, current annual disclosures about a reportable segment’s profit or loss and assets will be required on an interim basis. Entities will also be required to disclose information about the CODM’s title and position at the Company along with an explanation of how the CODM uses the reported measures of segment profit or loss in their assessment of segment performance and deciding whether how to allocate resources. Finally, ASU 2023-07 requires all segment disclosures for public entities that have only a single reportable segment. The amendments in ASU 2023-07 are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, and early adoption is permitted. The Company is currently evaluating the impact of ASU 2023-07 on its condensed consolidated financial statements.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740) (“ASU 2023-09”), which enhances the income tax disclosure requirements for public entities on an annual basis. Under ASU 2023-09, public entities will be required to disclose in their rate reconciliation, on an annual basis, both percentages and amounts in their reporting currency for certain categories in a tabular format, with accompanying qualitative disclosures. The amendments in ASU 2023-09 are effective for fiscal years beginning after December 15, 2024, and early adoption is permitted. The Company is currently evaluating the impact of ASU 2023-09 on its condensed consolidated financial statements.

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As described in Note 1, the Company completed its previously announced Merger with AVROBIO on June 20, 2024. The Merger was accounted for as a reverse recapitalization in accordance with GAAP with Legacy Tectonic as the accounting acquirer of AVROBIO. At the effective time of the Merger, substantially all the assets of AVROBIO consisted of cash and cash equivalents, as well as other nominal non-operating assets. Under such reverse recapitalization accounting, the assets and liabilities of AVROBIO were recorded at their fair value in AVROBIO’s financial statements at the effective time of the Merger, which approximated book value due to the short-term nature. No goodwill or intangible assets were recognized. Consequently, the condensed consolidated financial statements of the Company reflect the historical operations of Legacy Tectonic for accounting purposes together with the issuance of shares to the former shareholders of AVROBIO, the legal acquirer, and a recapitalization of the equity of Legacy Tectonic, the accounting acquirer. The exchange ratio was retroactively applied to all outstanding common shares, convertible preferred shares, stock options and restricted stock of Legacy Tectonic.

As part of the recapitalization, Legacy Tectonic obtained the assets and liabilities listed below:

The Company incurred transaction costs of $9.9 million, of which $8.2 million was recorded within accrued expenses and other current liabilities on the condensed consolidated balance sheet, $0.6 million was recorded within accounts payable on the condensed consolidated balance sheet and $1.2 million was paid in cash as of June 30, 2024. This amount was recorded as a reduction to additional paid-in capital in the condensed consolidated statements of convertible preferred stock and stockholders’ equity (deficit) for the three and six months ended June 30, 2024.

With respect to the CVRs issued in connection with the Merger, the Company believes that any receipt of payments resulting from an AVROBIO disposition of AVROBIO’s pre-closing assets described in the CVR Agreement are highly susceptible to factors outside the Company’s influence that are not expected to be resolved within the timeline outlined in the CVR Agreement, if at all. In particular, these amounts are primarily influenced by the actions and judgments of third parties and the buyers of such assets and are based on the buyers of such assets progressing the specific platform and intellectual property and early stage of research and development programs. If the Company were to record a receivable for such contingent payments, it would also record a corresponding liability. As of June 30, 2024, no receivables or liabilities were recorded on the condensed consolidated balance sheet relating to such contingent payments.

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The following tables present information about financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands):

As of June 30, 2024 and December 31, 2023, the Company’s cash equivalents, which were invested in money market funds, were valued based on Level 1 inputs.

There were no transfers between the Level 1, Level 2 or Level 3 categories during the six months ended June 30, 2024 and 2023.

SAFE Liabilities

From October through December 2023, Legacy Tectonic entered into multiple SAFE agreements with certain existing investors and received $34.1 million. Prior to redemption, the SAFE liabilities were valued using a probability weighted scenario analysis and discount rates derived by application of the build-up method to reflect the cost of equity. The valuation model required a variety of inputs, including the probability of occurrence of events that would trigger conversion or redemption of the SAFEs, the expected timing of such events, and a discount rate.

Upon the closing of the Merger, the principal balance of the SAFEs was automatically redeemed for 2,752,216 shares of Legacy Tectonic common stock at the conversion price of $12.40 per share immediately prior to the Merger closing. As such the valuation inputs utilized to adjust the SAFE liability to fair value upon the closing of the Merger was $12.40. At closing, shares of Legacy Tectonic common stock issued pursuant to the redemption of Legacy Tectonic SAFEs were converted into 1,470,839 shares of AVROBIO common stock based on the Exchange Ratio, pursuant to the Merger Agreement.

The following table presents activity for the SAFE liabilities that were measured at fair value using significant unobservable Level 3 inputs during the six months ended June 30, 2024 and the year ended December 31, 2023 (in thousands):

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Property, equipment and improvements, net is comprised of the following (in thousands):

Depreciation expense was $0.3 million and $0.2 million during the three months ended June 30, 2024 and 2023, respectively, and $0.5 million during each of the six months ended June 30, 2024 and 2023, which was recorded as follows (in thousands):

Accrued expenses and other current liabilities is comprised of the following (in thousands):

Leases

The Company’s commitments under its operating and finance leases are described in Note 8.

Harvard Agreement

In July 2020, Legacy Tectonic entered into an agreement with the President and Fellows of Harvard College (“Harvard”), for an option fee in the low five digits, whereby Harvard granted Legacy Tectonic an exclusive option to negotiate a worldwide, exclusive, royalty-bearing license under Harvard’s interest in the patent rights covering certain technology that was developed by Harvard. In October 2021, Legacy Tectonic exercised the option and on February 10, 2022, entered into a license agreement (“License Agreement”) with Harvard to conduct research and development activities using certain materials, technology and patent rights owned by Harvard, with the intent to develop, obtain regulatory approval for, and commercialize products. The License Agreement will remain in effect until the expiration of the last valid claim within the patent rights covering a product developed under the License Agreement or the termination of the License Agreement. Management concluded that the acquisition of patents and materials received under the License Agreement represents an asset acquisition of an in-progress research and development asset without future alternative use; therefore, any consideration paid was expensed.

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As consideration for the License Agreement, Legacy Tectonic agreed to pay Harvard a non-refundable license fee, consisting of a cash payment due in three equal annual installments, in total amounting to $170,000 and 227,486 shares of common stock. The installments became due on July 2, 2022 (“First Payment Due Date”) and the first and second anniversaries of the First Payment Due Date. The first payment of $56,666 was paid in July 2022. The common stock issued to Harvard had a fair value of $0.4 million. Both the cash payment and the issuance of shares were expensed to research and development during the year ended December 31, 2022. The second payment of $56,666 was made in July 2023. The remaining installment amount of $56,668 is due in July 2024.

The Company also will be responsible for payment of (1) annual maintenance fees ranging from the low five digits to the low six digits during the term of the License Agreement (through the first commercial sale of a royalty-bearing product); (2) royalty payments as a percentage in the low single digits of the annual net sales that the Company generates from products that utilize the license technology (“Licensed Products”) and royalty payments as a percentage in the low single digits of the annual net sales that the Company generates from know-how enabled product licenses (“Know-How Enabled Products”) and (3) a percentage between 10-20% of all non-royalty income received by the Company under sublicenses, strategic partnerships and know-how enabled product licenses that utilize the license technology. Subsequent to the first commercial sale of a royalty-bearing product, annual maintenance fees will increase to a low six digits for the remainder of the term of the License Agreement. The royalty term from sales of Licensed Products will terminate on a country-by-country and product-by-product basis on the earlier of (i) the expiration of the patent rights covering the product, expected to be no earlier than May 2041, and (ii) the termination of the License Agreement.

The royalty term from sales of Know-How Enabled Products will terminate on the earlier of (i) ten years after the first commercial sale of the first Know-How Enabled Product and (ii) twelve years after the first commercial sale of the first Licensed Product. There was $0.1 million due to Harvard as of June 30, 2024. During the three months ended June 30, 2024 and 2023, the Company paid less than $0.1 million and $0.1 million, respectively, and during the six months ended June 30, 2024 and 2023, the Company paid $0.1 million and $0.2 million, respectively, to Harvard.

Alloy Therapeutics License Agreement

On November 29, 2021, Legacy Tectonic executed a license agreement with Alloy Therapeutics, LLC (“ATX”), whereby the Company will use ATX technology for the purpose of preclinical development, clinical development and commercialization of potential product candidates, for an initial period of three years, with an option to extend the term for an additional two years. The Company will pay ATX a non-refundable and non-creditable annual fee of $0.1 million on each anniversary of the agreement. On November 7, 2022, Legacy Tectonic and ATX amended the agreement and extended the period of payment for the first fee due in May 2023. Additionally, the Company will be responsible for annual partnering fees if the Company decides to pursue clinical development of a product candidate using the ATX technology. The partnering fees may be creditable against future milestone development fees paid by the Company. The Company will also be responsible to pay ATX development milestone payments for the movement of certain product candidates through clinical trials, which range from the low six digits to the low seven digits upon completion of each milestone and amount to $4.8 million in total milestone payments under the license agreement. Provided the Company is able to commercialize a product using ATX technology, the Company will be responsible to pay ATX commercial payments in the low seven digits per year during the first six years of commercial sales, amounting to an amount in the high eight digits in total commercial payments under the license agreement.

During the three months ended June 30, 2024 and 2023, the Company paid $0 and $0.1 million to ATX, respectively, and during the six months ended June 30, 2024 and 2023, the Company paid $0.1 million and $0.1 million to ATX, respectively.

Adimab Agreement

On May 1, 2023, Legacy Tectonic entered into a discovery agreement with Adimab, LLC (“Adimab”), an antibody discovery company, whereby Legacy Tectonic and Adimab are collaborating on human antibody discovery in accordance with an agreed upon research program. Legacy Tectonic paid an upfront technology access fee totaling $20,000 upon execution of the agreement.

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The Company also will be responsible for payment of (1) quarterly funding equal to 100% of the actual full-time employee (“FTE”) expended by Adimab in the performance of its obligations in accordance with the agreed upon research program at an annual rate of $0.4 million per FTE (subject to annual consumer price index increases) per the agreement, (2) delivery fees equal to $0.1 million upon both Adimab’s initial delivery of sequences or physical materials and completion pursuant to the research program (initial and completion fees payable once per target for a total of up to $0.4 million), (3) a non-creditable, non-refundable fee of $0.5 million upon the exercise of an option to obtain the licenses and assignments for information discovered during the research program, (4) development milestone payments for the movement of certain product candidates thought clinical trials, which range in the low seven digits, and (5) royalty payments based on the annual net sales that the Company generates from products that utilize Adimab technology. The Company has the right to terminate the agreement if certain criteria are met. As of June 30, 2024, the Company recorded $0.1 million of costs associated with the FTEs in accrued expenses and other current liabilities and $0 of discovery delivery fees in accounts payable.

During the three months ended June 30, 2024 and 2023, the Company paid $0.2 million and less than $0.1 million to Adimab, respectively. During the six months ended June 30, 2024 and 2023, the Company paid $0.3 million and less than $0.1 million to Adimab, respectively.

Indemnification Agreements

In accordance with the Company’s amended and restated certificate of incorporation (“ARCOI”) and certain indemnification agreements, the Company indemnifies certain officers and directors for specified events or occurrences, subject to certain limits, in which the officer or director is or was serving at the Company’s request in such capacity.

The Company enters into certain types of contracts that contingently requires it to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s bylaws, under which it must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship with the Company, (ii) contracts under which it must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, and (iii) procurement, service or license agreements under which the Company may be required to indemnify vendors, service providers or licensees for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the its products, technology, intellectual property or services.

From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may cause a material adverse effect on future business, operating results or financial condition. It is not possible to estimate the maximum amount potentially payable under these contracts since there is no history of prior indemnification claims and the unique facts and circumstances involved in each particular claim will be determinative.

As of June 30, 2024 and December 31, 2023, the Company did not have any liabilities or other commitments related to indemnification claims.

Litigation

In the normal course of operations, the Company may become involved in various legal proceedings. As of June 30, 2024 and December 31, 2023, the Company has not recorded accruals for probable losses related to any existing or pending litigation as the Company’s management has determined that there are no matters where a potential loss is probable and reasonably estimable. The Company does not believe that any existing or pending claims would have a material impact on the Company’s condensed consolidated financial statements.

Legacy Tectonic has entered into operating leases for office and laboratory facilities and financing leases for laboratory equipment used in research and development activities. The remaining lease terms for its leases range from approximately two months to approximately 3.5 years. These leases often include options to extend the term of the lease. When it is reasonably certain that the option will be exercised, the impact of the renewal term is included in the lease term for purposes of determining total future lease payments and measuring the ROU asset and lease liability. The Company is not reasonably certain to exercise any available renewal options, which are therefore excluded from the measurement of leases. The Company applies the short-term lease policy election for its real estate and equipment leases, which allows it to exclude from recognition leases with an original term of twelve months or less.

In November 2020, Legacy Tectonic executed a facilities lease agreement to occupy 18,768 square feet of office and laboratory space, that was subsequently amended on April 21, 2022. The lease requires the Company to pay fixed base rent, which is included in the measurement of the lease, as well as its proportionate share of the facilities operating expenses which are treated as variable lease costs based on the Company’s election to combine lease and associated non-lease components and are excluded from the measurement of the lease. The lease expires on January 31, 2026, and contains a five-year renewal option exercisable by the Company which is not included in the measurement of the lease.

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The following table sets forth information about lease costs for the three and six months ended June 30, 2024 and 2023 (in thousands):

The following table sets forth information about the Company’s leases for the six months ended June 30, 2024 and 2023 (in thousands):

The following table presents the maturity of the Company’s finance and operating lease liabilities for as of ended June 30, 2024 (in thousands):

Convertible Preferred Stock

Prior to the conversion upon the closing of the Merger, Legacy Tectonic issued Series A-1, A-2, A-3 and A-4 convertible preferred stock (the “Preferred Stock”).

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Prior to the completion of the Merger, Legacy Tectonic classified the Preferred Stock outside of permanent equity as the shares had redemption features that were not entirely within the control of Legacy Tectonic.

Upon the closing of the Merger, all outstanding shares of the Preferred Stock were converted into 3,647,675 shares of common stock. No shares of the Preferred Stock were outstanding as of June 30, 2024.

Preferred Stock

Subsequent to consummation of the Merger, the Company authorized the issuance of 10,000,000 shares of new undesignated preferred stock, however no such shares were issued or outstanding as of June 30, 2024.

Common Stock

As of June 30, 2024 and as a result of the Merger, the Company’s ARCOI authorized the Company to issue 150,000,000 shares of voting common stock of $0.0001 par value common stock, of which 14,734,323 shares were issued and outstanding. Holders of voting common stock are entitled to one vote per share. In addition, holders of voting common stock are entitled to receive dividends, if and when declared by the Company’s Board of Directors. As of June 30, 2024, no dividends had been declared.

The Company has included in issued and outstanding common stock shares of restricted common stock granted by the Company. As of June 30, 2024, there were 14,734,323 shares of common stock issued and outstanding, of which 11,447 relate to shares of restricted common stock (see Note 10).

2019 Equity Incentive Plan

The Legacy Tectonic 2019 Equity Incentive Plan (the “2019 Plan”) provides employees, consultants and advisors and non-employee members of the Board of Directors and its affiliates with the opportunity to receive grants of stock options, stock awards and equity awards. Since inception, Legacy Tectonic has only issued stock options.

2024 Equity Incentive Plan

On June 20, 2024, the Company adopted the 2024 Equity Incentive Plan (the “2024 Plan”) which became effective upon completion of the Merger. The 2024 Plan provides for the grant of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards and other forms of awards to employees, consultants, and non-employee directors of the Company. The terms of stock award agreements, including vesting requirements, are determined by the Company’s Board of Directors and are subject to the provisions of the 2024 Plan. The term of each stock option shall be no more than ten years from the date of grant. Following the effectiveness of the 2024 Plan, no further grants will be made under the 2019 Plan; however, any outstanding equity awards granted under the 2019 Plan will continue to be governed by the terms of the 2019 Plan.

The 2024 Plan initially provided for the issuance of up to 1,938,799 shares of common stock (the “Initial Share Reserve”). Subject to any other adjustments as defined in the 2024 Plan, such aggregate number of shares of common stock will automatically increase on January 1st of each year for a period of ten years commencing on January 1, 2025 and ending on (and including) January 1, 2034, in an amount equal to 5% of the total number of shares of common stock issued and outstanding determined as of the day prior to such increase; provided, however that the board of directors may act prior to January 1st of a given year to provide that the increase for such year will be a lesser number of shares of common stock. The aggregate maximum number of shares of common stock that may be issued pursuant to the exercise of incentive stock options is three multiplied by the Initial Share Reserve.

As of June 30, 2024, there were 1,063,999 shares available for issuance under the 2024 Plan.

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2024 Employee Stock Purchase Plan

On June 20, 2024, the Company adopted the 2024 Employee Stock Purchase Plan (the “2024 ESPP”), which became effective upon completion of the Merger. The maximum number of shares of common stock that may be issued under the 2024 ESPP will not exceed 147,343 shares (the “Initial ESPP Share Reserve”), plus the number of shares of common stock that are automatically added on January 1st of each year for a period of up to ten years commencing on January 1, 2025 and ending on (and including) January 1, 2034, in an amount equal to the lesser of (x) 1% of the total number of shares of common stock issued and outstanding determined as of the day prior to such increase and (y) a number of shares equal to three times the Initial ESPP Share Reserve. Notwithstanding the foregoing, the Board of Directors may act prior to the first day of any calendar year to provide that there will be no January 1st increase in the share reserve for such calendar year or that the increase in the share reserve for such calendar year will be a lesser number of shares of common stock than would otherwise occur pursuant to the preceding sentence. No offering periods under the 2024 ESPP had been initiated as of June 30, 2024. The option activity below reflects the reverse stock split and retroactive application of the exchange ratio as discussed in Note 1.

A summary of the stock option activity for the six months ended June 30, 2024 is as follows (in thousands except share and per share amounts):

The weighted-average grant-date fair value of options granted during the six months ended June 30, 2024 and 2023 was $13.95 and $2.51 per share, respectively. The total intrinsic value of options exercised during the three months ended June 30, 2024 and 2023 was $3.7 million and $0, respectively, and was $3.7 million and less than $0.1 million during the six months ended June 30, 2024 and 2023, respectively. Forfeitures of options are recorded as incurred.

Cash received from option exercises was $0.6 million for the three and six months ended June 30, 2024 and $0 and less than $0.1 million for the three and six months ended June 30, 2023, respectively.

The fair values of the options granted in the six months ended June 30, 2023 were estimated based on the Black-Scholes-Merton option pricing model, using the following assumptions:

Restricted Common Stock

Since 2019, Legacy Tectonic has granted restricted common stock to founders, employees and consultants. The purchase price of the restricted common stock is the estimated fair value on the grant date and the restricted stock is subject to various vesting schedules. Unvested restricted common stock are subject to repurchase rights held by the Company at the original issuance price in the event the restricted common stockholders’ service to the Company is terminated either voluntarily or involuntarily. As of June 30, 2024, there were 11,447 shares of unvested restricted common stock, with a repurchase liability of less than $0.1 million, that is classified in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet.

The following table summarizes restricted stock activity:

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The weighted-average grant date fair value of unvested restricted common stock and restricted common stock vested and forfeited for the six months ended June 30, 2024 and 2023 was immaterial.

Stock-Based Compensation Expense

The Company recorded stock-based compensation expense regarding its employees and nonemployees as follows (in thousands):

The Company records compensation expense for options with service based vesting conditions on a straight-line basis over the vesting period. As of June 30, 2024, total compensation cost not yet recognized related to unvested stock options was $13.8 million, which is expected to be recognized over a weighted-average period of 3.4 years.

During the three and six months ended June 30, 2024 and 2023, the Company recorded no income tax provision or benefit.

The Company has evaluated the positive and negative evidence bearing upon its ability to realize its deferred tax assets, which primarily consist of net operating loss carryforwards. The Company has considered its history of cumulative net losses, estimated future taxable income and prudent and feasible tax planning strategies and has concluded that it is more likely than not that the Company will not realize the benefits of its deferred tax assets. As a result, as of June 30, 2024, the Company has maintained a full valuation allowance against its net deferred tax assets.

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts):

The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. For the three and six months ended June 30, 2024 and 2023, the Company excluded the following potential common shares from the computation of diluted net loss per share attributable to common stockholders for the period because including them would have had an anti-dilutive effect:

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Scientific Advisory Board Member

One of the Company’s co-founders and former director is a member of the Company’s Scientific Advisory Board (“SAB”) and meets the criteria of a related party. The Company paid the SAB member fees in the amount of less than $0.1 million during the three months ended June 30, 2024 and 2023, respectively, and less than $0.1 million during the six months ended June 30, 2024 and 2023 for advisory services provided. There was less than $0.1 million and $0 due to this related party as of June 30, 2024 and December 31, 2023.

License Agreement

Harvard meets the criteria of a related party resulting from the Company’s co-founders’ employment as professors in the Harvard Department of Molecular Pharmacology. Additionally, both co-founders were members of the Board during the six months ended June 30, 2024 and one co-founder is a major shareholder in the Company. Core intellectual property utilized by the Company is licensed from Harvard in exchange for license fees, future milestones and royalties, and equity in the Company in the form of common stock.

For the six months ended June 30, 2024 and 2023, the Company paid Harvard $0.1 million and $0.2 million in cash considerations, respectively (see Note 7). Accounts payable to Harvard amounted to less than $0.1 million and $0.1 million as of June 30, 2024 and December 31, 2023, respectively.

SAFE Agreements

From October through December 2023, Legacy Tectonic entered into multiple SAFE agreements with certain existing investors and received $34.1 million representing the purchase amount. All investors were considered related parties of the Company. The SAFE agreements had no maturity date, bore no interest, and were redeemable by Legacy Tectonic upon the occurrence of a triggering event, including the Merger which qualified as a public listing transaction under the SAFE agreements.

As discussed in Note 4, the SAFEs were redeemed for shares of Legacy Tectonic common stock in connection with the closing of the Merger.

The Company has a 401(k) retirement plan (the “Plan”) that covers eligible U.S. employees. Eligible employees may elect to contribute up to the maximum limits, as set by the Internal Revenue Service, of their eligible compensation. The Company’s funding policy is to contribute 3% (“Nonelective Contribution”) of employees’ eligible pay to the Plan. Highly compensated employees (as defined by the Plan) are not eligible to receive the Nonelective Contribution. The Company’s contributions were $0.1 million during each of the three and six months ended June 30, 2024 and 2023 and were recorded as follows:

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our unaudited condensed consolidated financial statements and the related notes included elsewhere in this Quarterly Report. In addition to historical information, the following discussion contains forward-looking statements. Our actual results may differ significantly from those projected in the forward-looking statements. Factors that might cause future results to differ materially from those projected in the forward-looking statements include, but are not limited to, those discussed in the sections entitled “Risk Factors” and “Special Note Regarding Forward-Looking Statements” in this Quarterly Report.

Unless otherwise indicated or the context otherwise requires, references in this “Management’s Discussion and Analysis of Financial Condition and Results of Operations” section to the Company, “we,” “us,” and “our” refer to the business and operations of Tectonic Operating Company, Inc. (previously Tectonic Therapeutic, Inc., referred to as “Legacy Tectonic”) and its consolidated subsidiaries prior to the Merger, and the business and operations of Tectonic Therapeutic, Inc. (previously AVROBIO, Inc., referred to as “AVROBIO”) and its consolidated subsidiaries following the Merger.

Overview

We are 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”). The discovery of biologics that can modulate GPCRs has historically been quite challenging. We have developed a proprietary technology platform called GEODe^™, with the aim of addressing these challenges to enable the discovery and development of GPCR-targeted biologic medicines that can modify the course of disease. We focus 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 or extend duration of life.

GPCRs are receptor molecules found on the surface of cells that act as sensors for various extracellular stimuli to enable communication between cells and their environment. These molecules regulate diverse aspects of human biology including blood pressure, glucose metabolism, transmission between neurons and immune surveillance. There are over 800 human genes encoding GPCRs, underscoring the extent to which nature has relied on this molecular system for physiological control. The breadth of effects controlled by GPCRs is best illustrated by the fact that greater than 30% of all approved drugs address targets in this class. The vast majority of these drugs, however, are small molecules, and their targets have been largely confined to a few GPCR subfamilies, many of which have a natural ligand that is also a small molecule. We believe there are many situations where biologics could present advantages over small molecules for this class of targets. For instance, when targeting a single member of a highly related family of GPCRs, the selectivity profile achievable with an antibody may be preferable to that of a small molecule to optimize therapeutic efficacy and safety for the patient. Conversely, when multi-modal action is needed to achieve a desired physiological effect, proteins engineered for bispecific function allow for dual target engagement, unlike small molecules that are generally optimized for action on a single target. We are focused on developing biologics to address GPCRs with the goal of capturing such opportunities.

It has been historically difficult, however, to discover therapeutic proteins and antibodies that bind to and modulate the activity of GPCRs because of the low endogenous level of expression of many GPCRs, complex biochemistry and their inherent instability when removed from their natural environment, the cell membrane. With the goal of unlocking the potential for biologic therapeutics to broaden the clinical utility of GPCRs, we use our proprietary GEODe^™ technology platform in an attempt to overcome the known challenges of GPCR-targeted drug discovery.

Our lead asset, TX45, is an Fc-relaxin fusion molecule that activates the RXFP1 receptor, the GPCR target of the hormone, relaxin. Relaxin is an endogenous protein, expressed at low levels in both men and women. 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. It has long been hypothesized that these unique dual aspects of relaxin biology may offer therapeutic potential in the treatment of cardiovascular disease.

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Unfortunately, the development of a viable therapeutic has been challenging, primarily because of relaxin’s very short half-life. We believe TX45’s pharmacological profile, the direct result of applying our protein engineering capabilities, has the potential to overcome the limitations that have impeded previous attempts to develop relaxin as a therapeutic protein. To interrogate the therapeutic potential of relaxin, we have identified: Group 2 Pulmonary Hypertension (“PH”) in the setting of Heart Failure with Preserved Ejection Fraction (“HFpEF”), referred to as Group 2 PH / HFpEF hereafter, as the initial disease setting. We hypothesize that in this setting, treatment with relaxin could improve hemodynamics through effects on pulmonary and systemic vasodilation, cardiac diastolic remodeling and potential remodeling in both the pulmonary vessels and the heart which could translate into a clinically meaningful improvement in exercise capacity in these patients. Clinical trials are planned to confirm this hypothesis. Despite this belief, our business carries substantial risks, including our limited experience in therapeutic discovery and development, and the risk that the platform may never result in the regulatory approval of a product candidate.

Since our inception in 2019, our operations have focused on organizing and staffing our company, business planning, raising capital, establishing our intellectual property portfolio and conducting preclinical studies and clinical trials. We do not have any product candidates approved for sale and have not generated any revenue from product sales. We have funded our operations primarily with proceeds from sales of Series A-1, A-2, A-3, and A-4 convertible preferred stock (collectively, the “Preferred Stock”), proceeds received from the Merger (as defined below), proceeds from the issuance of common stock, proceeds from issuance of convertible promissory notes, which were all converted to convertible preferred stock in March 2021 and proceeds from issuance of Simple Agreements for Future Equity (“SAFEs”) in October and December 2023. From inception through June 30, 2024, we have received $288.6 million in capital contributions from sales of Preferred Stock, issuance of convertible promissory notes, proceeds from issuance of SAFEs, proceeds from the Merger and proceeds from the issuance of common stock. As of June 30, 2024, we had $185.1 million in cash and cash equivalents. Based on our current operating plan, we believe that our existing cash and cash equivalents should be sufficient to fund our operations for at least the next twelve months following the issuance of our interim condensed consolidated financial statements.

Since inception, we have incurred significant operating losses. Our net losses were $12.7 million and $10.5 million for the three months ended June 30, 2024 and 2023, respectively, and $27.9 million and $24.9 million for the six months ended June 30, 2024 and 2023, respectively. As of June 30, 2024, we had an accumulated deficit of $118.5 million. We expect to continue to incur significant expenses and operating losses for the foreseeable future. We anticipate that our expenses will increase significantly in connection with our ongoing activities, as we:

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We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for one or more of our product candidates. If we obtain regulatory approval for any of our product candidates and do not enter into a commercialization partnership, we expect to incur significant expenses related to developing our internal commercialization capability to support product sales, marketing and distribution. Further, we will continue to incur additional costs associated with operating as a public company. As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy.

Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity offerings, debt financings or other capital sources, which may include collaborations with other companies, marketing, distribution or licensing arrangements with third parties, or other strategic transactions. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on favorable terms, or at all. If we fail to raise capital or enter into such agreements as and when needed, we may have to significantly delay, reduce or eliminate our product discovery and development programs or commercialization efforts.

Because of the numerous risks and uncertainties associated with pharmaceutical product development, we are unable to accurately predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.

Recent Developments

Merger with AVROBIO

On January 30, 2024, Legacy Tectonic entered into the Agreement and Plan of Merger and Reorganization (“Merger Agreement”) with AVROBIO and Alpine Merger Subsidiary, Inc. (“Merger Sub”). Pursuant to the Merger Agreement and the satisfaction of the conditions described in the Merger Agreement, on June 20, 2024, Merger Sub merged with and into Legacy Tectonic, with Legacy Tectonic surviving as a wholly owned subsidiary of AVROBIO (the “Merger”). The Merger Agreement and the transactions contemplated therein were approved by the members of the AVROBIO board of directors and Legacy Tectonic board of directors. Subject to the terms and conditions of the Merger Agreement, at the effective time, (a) each outstanding share of Legacy Tectonic common stock (including shares of Legacy Tectonic common stock issued upon conversion of its preferred stock and the shares issued pursuant to that certain Subscription Agreement dated January 30, 2024, entered into among Legacy Tectonic and the investors party thereto (the “Subscription Agreement”) and conversion of the SAFEs into the right to receive a number of shares of AVROBIO common stock equal to the exchange ratio; and (b) each then outstanding Legacy Tectonic stock option that was outstanding and unexercised immediately prior to the effective time was assumed by AVROBIO, subject to the exchange ratio.

Immediately after the Merger, AVROBIO securityholders as of immediately prior to the Merger owned approximately 24.8% of the outstanding shares of our capital stock on a diluted basis. Immediately after the Merger, Legacy Tectonic securityholders owned approximately 38.5% of the outstanding shares of our capital stock on a diluted basis. Investors participating in the Subscription Agreement and the SAFEs owned approximately 27.1% and 9.6% of the outstanding shares of our capital stock, respectively, on a diluted basis.

Legacy Tectonic stockholders received approximately 10,956,614 shares of AVROBIO common stock in connection with the Merger, including 11,448 shares of AVROBIO common stock subject to vesting terms, based on the number of shares of Legacy Tectonic common stock outstanding immediately prior to the Merger, including Legacy Tectonic restricted stock, the number of shares of Legacy Tectonic common stock issued to investors participating in the Subscription Agreement and SAFEs, and Legacy Tectonic convertible preferred stock outstanding immediately prior to the Merger, which was converted into shares of Legacy Tectonic common stock on a one-for-one basis immediately prior to the closing of the Merger.

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Tectonic Subscription Agreement

Concurrently with the closing of the Merger, on June 20, 2024, certain investors completed the purchase of shares of Legacy Tectonic common stock pursuant to the Subscription Agreement at a price of approximately $12.40 per share for an aggregate purchase price of approximately $96.6 million. The shares of Legacy Tectonic common stock that were issued pursuant to the Subscription Agreement were converted into 4,163,606 shares of our common stock upon the closing of the Merger based on the exchange ratio, pursuant to the Merger Agreement.

Macroeconomic Considerations

Uncertainty in the global economy presents significant risks to our business. We are subject to continuing risks and uncertainties in connection with the current macroeconomic environment, including rising interest rates, recent bank failures and geopolitical factors, such as tensions involving China and the United States, the war between Russia and Ukraine and the conflict in the Middle East and the responses thereto. While we are closely monitoring the impact of the current macroeconomic conditions on all aspects of our business, including the impacts on our participants in our clinical trials, employees, suppliers, vendors and collaboration partners, the ultimate extent of the impact on our business remains highly uncertain and will depend on future developments and factors that continue to evolve. Most of these developments and factors are outside our control and could exist for an extended period of time. We will continue to evaluate the nature and extent of the potential impacts to our business, results of operations, liquidity and capital resources.

Revenue

We have not generated any revenue since our inception and do not expect to generate any revenue from the sale of products in the foreseeable future, if at all. If our development efforts for our product candidates are successful and result in regulatory approval, or in collaboration or license agreements with third parties, we may generate revenue in the future from product sales or payments from collaboration or license agreements that we may enter into with third parties, or any combination thereof. We cannot predict if, when or to what extent we will generate revenue from the commercialization and sale of our product candidates. We may never succeed in obtaining regulatory approval for any of our product candidates.

Operating Expenses

Research and Development

Research and development expenses consist of costs incurred for our research activities, including our discovery efforts and the development of our programs and platform. These expenses include:

We expense all research and development costs in the periods in which they are incurred. Costs for certain development activities are recognized based on our evaluation of the progress to completion of specific tasks using information and data provided to us by our vendors and third-party service providers. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. Such amounts are recognized as an expense when the goods have been delivered or the services have been performed, or when it is no longer expected that the goods will be delivered or the services rendered. Upfront payments under license agreements are expensed upon receipt of the license, and annual maintenance fees under license agreements are expensed in the period in which they are incurred. Milestone payments under license or collaboration agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable.

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Our direct research and development expenses relate to the development of our lead product candidate, TX45, as well as the nonclinical safety pharmacology and toxicology testing of our product candidates. Our external services expenses consist of the external costs and fees paid to consultants and other research laboratories in connection with our preclinical development and clinical development activities.

Costs that are deployed across multiple of our programs, including the HHT program and programs aimed at the discovery and development of potential therapies for fibrotic disease, and our platform technology and are not directly attributable to any single program are not allocated to any single program and, as such, are not separately classified. These costs include multi-program employee costs, cross-program payments made under third-party licensing agreements, costs of laboratory supplies and facilities expenses, including rent, depreciation and other indirect costs, the costs of our discovery efforts and projects are included in unallocated employee-related expenses, laboratory supplies and other expenses.

Research and development activities are central to our business model. Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of our product candidates due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to which product candidates to pursue and how much funding to direct to each product candidate on an ongoing basis in response to the results of ongoing and future preclinical studies and clinical trials, regulatory developments and our ongoing assessments as to each product candidate’s commercial potential. We will need to raise substantial additional capital in the future. Our clinical development costs are expected to increase significantly as we commence clinical trials. Our future expenses may vary significantly each period based on factors such as:

General and Administrative

General and administrative expenses consist primarily of salaries and personnel-related costs, including share-based compensation, for our personnel in executive, legal, finance and accounting, human resources and other administrative functions. General and administrative expenses also include legal fees relating to patents and corporate matters, professional fees paid for accounting, auditing, consulting and tax service, insurance costs, travel expenses, office and information technology costs and facilities, depreciation and other expenses related to general and administrative activities, which include direct or allocated expenses for rent and maintenance of facilities and utilities.

We anticipate that our general and administrative expenses will increase in the future as we expect to incur significantly increased accounting, audit, legal, regulatory, compliance, director and officer insurance, and investor and public relations expenses associated with operating as a public company. We also expect to incur additional intellectual property-related expenses as we file patent applications to protect innovations arising from our research and development activities.

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Other (Expense) Income, Net

Loss on Issuance of SAFE Liabilities and Change in Fair Value of SAFE Liabilities

In October and December 2023, Legacy Tectonic issued SAFEs for proceeds of $34.1 million. The SAFEs were recorded as liabilities in the consolidated balance sheet at their fair value on the issuance dates. Until redemption, the SAFEs were measured at a fair value on a recurring basis, with subsequent changes in fair value recorded in other income and expenses on the consolidated statement of operations and comprehensive loss. We recorded a loss of $3.6 million resulting from the remeasurement of the SAFEs to fair value from March 31, 2024 to June 20, 2024.

Immediately prior to the closing of the Merger, the principal balance of the SAFEs was automatically redeemed into 2,752,216 shares of Legacy Tectonic’s common stock at the conversion price of approximately $12.40 per share. At the closing of the Merger, shares of Legacy Tectonic common stock issued pursuant to the redemption of the SAFEs were converted into 1,470,839 shares of our common stock based on the exchange ratio, pursuant to the Merger Agreement.

Interest Income

Interest income primarily consists of interest earned on our invested cash balances, which consist of deposit accounts and a sweep account.

Interest Expense

Interest expense primarily consists of interest expense on finance lease liabilities.

Other Expense

Other expense primarily consists of the difference between transactional currency and functional currency.

Income Taxes

Since our inception, we have not recorded any income tax benefits for the net losses we have incurred or for the research and development tax credits earned in each year by our operations in the United States, as we believe, based upon the weight of available evidence, that it is more likely than not that all of our net operating loss carryforwards and tax credit carryforwards will not be realized.

Components of Results of Operations

Comparison of the Three Months Ended June 30, 2024 and 2023

The following table summarizes our results of operations for the three months ended June 30, 2024 and 2023: