The Company and Basis of Presentation	6 Months Ended
The Company and Basis of Presentation	Jun. 30, 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 committed to developing next-generation therapies that elevate the standard in immunology by delivering more complete disease control, greater durability, and a simpler treatment experience for patients. 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., a 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 contingent value rights agreement (the "CVR Agreement") we entered into with Equiniti Trust Company LLC (f/k/a American Stock Transfer & Trust Company LLC) as rights agent in connection with the Asset Acquisition, 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 “2024 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 and six months ended June 30, 2026, the Company sold an aggregate of nil and 296,396, respectively, shares of common stock under the ATM offering program pursuant to the 2024 Sales Agreement resulting in net proceeds of $9.7 million. The 2024 Sales Agreement was terminated on June 26, 2026 and the Company concurrently entered into a new sales agreement (the “2026 Sales Agreement”) with TD Securities (USA) LLC as its agent, pursuant to which the Company may issue and sell up to $500.0 million of shares of common stock under an ATM offering program. During the three months ended June 30, 2026, the Company did not sell any shares under the ATM offering program pursuant to the 2026 Sales Agreement. As of June 30, 2026, $500.0 million remained available for sale under the 2026 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 $435.2 million after deducting approximately $28.2 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 June 30, 2026, the Company has funded its operations by raising an aggregate of approximately $2.1 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 June 30, 2026, Spyre had an accumulated deficit of $1.2 billion, and cash, cash equivalents, and marketable securities of $1.1 billion. 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 June 30, 2026, and its results of operations for the three and six months ended June 30, 2026 and 2025, changes in convertible preferred stock and stockholders’ equity for the three and six months ended June 30, 2026 and 2025, and cash flows for the six months ended June 30, 2026 and 2025. The results of operations for the three and six months ended June 30, 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 U.S. Securities and Exchange Commission (“SEC”) on February 19, 2026.