The Company and Basis of Presentation

3 Months Ended

Mar. 31, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The Company and Basis of Presentation

The Company and Basis of Presentation

Spyre Therapeutics, Inc., formerly Aeglea BioTherapeutics, Inc. (“Spyre” or the “Company”), is a clinical stage biotechnology company focused on developing next generation therapeutics for patients living with inflammatory bowel disease (“IBD”) and rheumatic diseases (“RD”). The Company was formed as a Limited Liability Company in Delaware on December 16, 2013 under the name Aeglea BioTherapeutics Holdings, LLC and was converted from a Delaware LLC to a Delaware corporation on March 10, 2015. On June 22, 2023, the Company acquired the assets of Spyre Therapeutics, Inc., privately held biotechnology company (the “Asset Acquisition”), and on November 27, 2023, the Company completed its corporate rebranding, changing the name of the Company to Spyre Therapeutics, Inc. The Company operates in one segment and has its principal offices in Waltham, Massachusetts.

In connection with the Asset Acquisition, a non-transferable contingent value right (“CVR”) was distributed to stockholders of record of the Company as of the close of business on July 3, 2023 (the “Legacy Stockholders”). Holders of the CVRs will be entitled to receive certain cash payments from proceeds received by the Company prior to the third anniversary of the CVR Agreement, if any, related to the disposition or monetization of its legacy assets during the one-year period following the closing of the Asset Acquisition.

On September 6, 2024, the Company entered into a sales agreement (the “Sales Agreement”) with TD Securities (USA) LLC as its agent, pursuant to which the Company may issue and sell up to $200.0 million of shares of common stock under an at-the-market (“ATM”) offering program. During the three months ended March 31, 2026, the Company sold an aggregate of 296,396 shares of common stock under the ATM offering program at an average price per share of $33.566 resulting in net proceeds of $9.7 million after deducting sales agent commissions and other offering costs of $0.2 million. As of March 31, 2026, $154.1 million remained available for sale under the Sales Agreement.

On October 13, 2025, the Company entered into an underwriting agreement (the “October 2025 Underwriting Agreement”), pursuant to which the Company sold an aggregate of 17,094,594 shares of its common stock, inclusive of 2,229,729 shares pursuant to the full exercise of the underwriters' over-allotment option, at a public offering price per share of $18.50, resulting in net proceeds of approximately $296.4 million after deducting approximately $19.9 million of underwriting discounts and other offering costs (the “October 2025 Offering”). The over-allotment option was exercised in full on October 14, 2025 and the transaction closed on October 15, 2025.

On April 13, 2026, the Company entered into an underwriting agreement (the “April 2026 Underwriting Agreement”), pursuant to which the Company sold an aggregate of 7,475,000 shares of its common stock, inclusive of 975,000 shares pursuant to the full exercise of the underwriters' over-allotment option, at a public offering price per share of $62.00, resulting in net proceeds of approximately $435.3 million after deducting approximately $28.1 million of underwriting discounts and other offering costs (the “April 2026 Offering”). The over-allotment option was exercised in full on April 15, 2026 and the transaction closed on April 16, 2026.

Liquidity

The Company is a clinical stage biotechnology company with a limited operating history, and due to its significant research and development expenditures, the Company has generated operating losses since its inception and has not generated any revenue from the commercial sale of any products. There can be no assurance that profitable operations will ever be achieved, and, if achieved, whether profitability can be sustained on a continuing basis.

Since its inception and through March 31, 2026, the Company has funded its operations by raising an aggregate of approximately $1.7 billion of gross proceeds from the sale and issuance of convertible preferred stock and common stock, pre-funded warrants, the collection of grant proceeds, and the licensing of its product rights for commercialization of pegzilarginase in Europe and certain countries in the Middle East. As of

March 31, 2026, Spyre had an accumulated deficit of $1.2 billion, and cash, cash equivalents, and marketable securities of $741.5 million.

Based on its current operating plans, the Company has sufficient resources to fund operations for at least one year from the issuance date of these financial statements with existing cash, cash equivalents, and marketable securities. The Company will need to secure additional financing in the future to fund additional research and development, and before a commercial drug can be produced, marketed and sold. If the Company is unable to obtain additional financing or generate license or product revenue, the lack of liquidity could have a material adverse effect on the Company.

Basis of Presentation

The consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States (“U.S. GAAP”) as defined by the Financial Accounting Standards Board (“FASB”) and include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Unaudited Interim Financial Information

The interim condensed consolidated financial statements included in this Quarterly Report on Form 10-Q are unaudited. The unaudited interim financial statements have been prepared on the same basis as the annual financial statements and reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for a fair statement of the Company’s financial position as of March 31, 2026, and its results of operations for the three months ended March 31, 2026 and 2025, changes in convertible preferred stock and stockholders’ equity for the three months ended March 31, 2026 and 2025, and cash flows for the three months ended March 31, 2026 and 2025. The results of operations for the three months ended March 31, 2026, are not necessarily indicative of the results to be expected for the year ending December 31, 2026 or for any other future annual or interim period. The December 31, 2025 balance sheet was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP for complete financial statements. These financial statements should be read in conjunction with the audited financial statements included in the Company’s Form 10-K for the year ended December 31, 2025 (the “Annual Report”) as filed with the SEC on February 19, 2026.