Spyre Therapeutics, Inc. (SYRE)

CIK: 0001636282. SIC: 2834 Pharmaceutical Preparations. Latest 10-K as of: 2026-02-19.

SIC breadcrumb: Manufacturing > Chemicals And Allied Products > SIC 2834 Pharmaceutical Preparations

SEC company page: https://www.sec.gov/edgar/browse/?CIK=1636282. Latest filing source: 0001636282-26-000020.

Selected Fundamentals

Financials

Annual standardized facts from SEC companyfacts as of latest extracted filing date 2026-02-19. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001636282.json. Derived margins, ratios, and free cash flow are computed from the extracted annual SEC facts.

Flow metrics use full-year FY periods from 10-K/10-K/A filings; balance-sheet metrics use FY-end instants. Free cash flow = operating cash flow - capital expenditures. Missing metrics are omitted rather than fabricated.

Ratios

ROE and ROA use period-end equity/assets. Liabilities / equity uses total liabilities divided by stockholders' equity. Current ratio uses current assets divided by current liabilities when both are reported.

Financial Charts

Quarterly

Quarterly standardized facts from SEC companyfacts as of latest extracted filing date 2026-05-05. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001636282.json.

Flow metrics use discrete quarter-length periods from 10-Q/10-Q/A filings. Q4 revenue and net income are derived only when annual FY and nine-month YTD facts exist for the same fiscal year; derived Q4 values are labeled. EPS Q4 is not derived.

Quarterly Charts

Macro Cross-References

• CPIAUCSL - Consumer Price Index for All Urban Consumers: All Items in U.S. City Average
• UNRATE - Unemployment Rate
• FEDFUNDS - Federal Funds Effective Rate
• CES0500000003 - Average Hourly Earnings of All Employees, Total Private
• DFEDTARU - Federal Funds Target Range - Upper Limit
• DFEDTARL - Federal Funds Target Range - Lower Limit
• DGS3MO - Market Yield on U.S. Treasury Securities at 3-Month Constant Maturity
• DGS2 - Market Yield on U.S. Treasury Securities at 2-Year Constant Maturity
• DGS10 - Market Yield on U.S. Treasury Securities at 10-Year Constant Maturity
• DGS30 - Market Yield on U.S. Treasury Securities at 30-Year Constant Maturity
• T10Y2Y - 10-Year Treasury Constant Maturity Minus 2-Year Treasury Constant Maturity
• CPILFESL - Consumer Price Index for All Urban Consumers: All Items Less Food and Energy
• CPIUFDSL - Consumer Price Index for All Urban Consumers: Food
• CPIENGSL - Consumer Price Index for All Urban Consumers: Energy
• CUSR0000SAH1 - Consumer Price Index for All Urban Consumers: Shelter
• PCEPI - Personal Consumption Expenditures: Chain-type Price Index
• PCEPILFE - Personal Consumption Expenditures Excluding Food and Energy: Chain-type Price Index
• PPIACO - Producer Price Index by Commodity: All Commodities
• T10YIE - 10-Year Breakeven Inflation Rate
• U6RATE - Total Unemployed, Plus All Marginally Attached Workers Plus Total Employed Part Time for Economic Reasons
• PAYEMS - All Employees, Total Nonfarm
• CIVPART - Labor Force Participation Rate
• EMRATIO - Employment-Population Ratio
• UNEMPLOY - Unemployed
• CE16OV - Employment Level
• ICSA - Initial Claims
• JTSJOL - Job Openings: Total Nonfarm
• JTSQUR - Quits: Total Nonfarm
• GDPC1 - Real Gross Domestic Product
• A191RL1Q225SBEA - Real Gross Domestic Product: Percent Change from Preceding Period
• INDPRO - Industrial Production: Total Index
• TCU - Capacity Utilization: Total Index
• HOUST - New Privately-Owned Housing Units Started: Total Units
• PERMIT - New Privately-Owned Housing Units Authorized in Permit-Issuing Places: Total Units
• RSAFS - Advance Retail Sales: Retail Trade
• PCE - Personal Consumption Expenditures
• DSPIC96 - Real Disposable Personal Income
• PSAVERT - Personal Saving Rate
• M2SL - M2
• BOPGSTB - U.S. International Trade in Goods and Services: Balance
• MSPUS - Median Sales Price of Houses Sold for the United States
• HSN1F - New One Family Houses Sold: United States
• RHORUSQ156N - Homeownership Rate in the United States
• TTLCONS - Total Construction Spending: Total Construction in the United States
• RRVRUSQ156N - Rental Vacancy Rate in the United States
• TOTALSL - Total Consumer Credit Owned and Securitized
• REVOLSL - Revolving Consumer Credit Owned and Securitized
• DRCCLACBS - Delinquency Rate on Credit Card Loans, All Commercial Banks
• GDP - Gross Domestic Product
• GPDI - Gross Private Domestic Investment
• GCE - Government Consumption Expenditures and Gross Investment
• PCEC - Personal Consumption Expenditures
• NETEXP - Net Exports of Goods and Services
• GFDEBTN - Federal Debt: Total Public Debt
• GFDEGDQ188S - Federal Debt: Total Public Debt as Percent of Gross Domestic Product
• FYFSD - Federal Surplus or Deficit
• FGRECPT - Federal Government Current Receipts
• FGEXPND - Federal Government: Current Expenditures
• MANEMP - All Employees, Manufacturing
• USCONS - All Employees, Construction
• USTRADE - All Employees, Retail Trade
• USFIRE - All Employees, Financial Activities
• USGOVT - All Employees, Government
• AWHAETP - Average Weekly Hours of All Employees, Total Private
• DGORDER - Manufacturers' New Orders: Durable Goods
• NEWORDER - Manufacturers' New Orders: Nondefense Capital Goods Excluding Aircraft
• BUSINV - Total Business Inventories
• EXPGS - Exports of Goods and Services
• IMPGS - Imports of Goods and Services
• IR - Import Price Index (End Use): All Commodities
• PPIFIS - Producer Price Index by Commodity: Final Demand

Latest quarter (10-Q)

Latest 10-Q source: 0001636282-26-000050.

Extracted structurally from real Item 2 body heading to real Item 3/4 boundary. Confidence: high. Filing date: 2026-05-05. Report date: 2026-03-31.

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 in conjunction with our unaudited condensed consolidated financial statements and related notes included in Part I, Item 1 of this Quarterly Report for the quarterly period ended March 31, 2026 (this “Quarterly Report”) as well as the audited consolidated financial statements and notes and Management’s Discussion and Analysis of Financial Condition and Results of Operations, included in our Annual Report on Form 10-K for the year ended December 31, 2025 (the “Annual Report”) filed with the U.S. Securities and Exchange Commission (the “SEC”) on February 19, 2026. This discussion and other parts of this Quarterly Report contain forward-looking statements that involve risks and uncertainties, such as statements regarding our expected results, outcomes, and the timing of these results and outcomes, plans, objectives, expectations and intentions. As a result of many factors, including those factors set forth in the “Risk Factors” section of this Quarterly Report, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. As used in this report, unless the context suggests otherwise, “we”, “us”, “our”, “the Company,” or “Spyre” refers to Spyre Therapeutics, Inc. and its consolidated subsidiaries taken as a whole.

Overview

We are a biotechnology company pioneering long-acting antibodies and antibody combinations to redefine the standard of care for inflammatory bowel disease (“IBD”) and rheumatic diseases. Our pipeline includes extended half-life antibodies targeting α4β7, TL1A, and IL-23 in development as monotherapies and pair-wise combinations..

Our Strategy

Our goal is to develop next-generation therapeutics to redefine the standard of care for the treatment of IBD and other immune-mediated diseases, relying on three strategic pillars:

•Advancing a portfolio of next-generation monotherapies - novel antibody candidates engineered for optimized potency, selectivity, and pharmacokinetics (“PK”) against validated IBD targets

•Evaluating paradigm-changing IBD combinations - fixed-dose-combinations of our engineered investigational antibodies designed to enable superior efficacy, safety, and convenience

•Expansion of our anti-TL1A program into additional indications - pipeline-in-a-product potential in diseases with first-in-class and best-in-class opportunity, starting with rheumatoid arthritis (“RA”), psoriatic arthritis (“PsA”), and axial spondyloarthritis (“axSpA”)

Our Portfolio and Development Plan Updates

We are advancing a pipeline of monoclonal antibodies (“mAbs”) for the treatment of IBD and other immune-mediated diseases. The following table (Figure 1) summarizes our pipeline and development strategy, including our SKYLINE Phase 2 platform trial evaluating SPY001, SPY002, SPY003, and pairwise combinations thereof in subjects with moderately to severely active UC and our SKYWAY basket trial evaluating SPY072 in three rheumatic diseases: RA, PsA, and axSpA:

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Figure 1. Spyre portfolio

SKYLINE Phase 2 Platform Trial in UC

In May 2025, we initiated our SKYLINE Phase 2 platform trial evaluating SPY001, SPY002, SPY003, as well as pairwise combinations thereof (six investigational agents in total), in subjects with moderately to severely active UC (Figure 2). The trial consists of two parts:

•Part A: Open-label assessment of the safety and preliminary efficacy of a single dose level of each investigational monotherapy. Enrollment for Part A has completed, with initial SPY001 Part A topline induction data announced in April 2026, and initial topline data expected for SPY002 and SPY003 in mid-2026 and the third quarter of 2026, respectively.

•Part B: Randomized and placebo-controlled assessment of the safety and efficacy of monotherapies and combinations, designed to provide dose-ranging data on monotherapies, proof-of-concept and contribution of components for combinations, with induction data expected in 2027.

SKYLINE is currently enrolling subjects into Part B of the trial.

Figure 2. SKYLINE trial design

mMS=modified mayo score; RHI=Robarts Histopathology Index; HEMI=Histo-Endoscopic Mucosal Improvement; P=primary endpoint; S=secondary endpoint. Initiation of each cohort subject to regulatory clearance.

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SKYWAY Phase 2 Basket Trial in Rheumatic Diseases (RA, PsA, axSpA)

In September 2025, we initiated our SKYWAY Phase 2 randomized and placebo-controlled basket trial of SPY072 in subjects with moderately to severely active RA, PsA, or axSpA (Figure 3). The trial consists of three sub-studies:

•RA sub-study: Double-blind, placebo-controlled safety and efficacy study of two dose levels of SPY072 at Week 12 with open-label follow-up through Week 36. This sub-study has completed enrollment ahead of schedule and topline proof-of-concept data are expected in the third quarter of 2026.

•PsA sub-study: Double-blind, placebo-controlled safety and efficacy study of a single dose level of SPY072 at Week 16 with open-label follow-up through Week 40. Enrollment continues in this sub-study and topline proof-of-concept data are expected in the fourth quarter of 2026.

•axSpA sub-study: Double-blind, placebo-controlled safety and efficacy study of a single dose level of SPY072 at Week 16 with open-label follow-up through Week 40. Enrollment continues in this sub-study and topline proof-of-concept data are expected in the fourth quarter of 2026.

Figure 3. SKYWAY trial design

RF=rheumatoid factor; ACPA= Anti-citrullinated protein antibodies; cs/b/tsDMARD=conventional synthetic, biologic, or targeted synthetic disease modifying antirheumatic drugs; BASDAI=Bath Ankylosing Spondylitis Disease Activity Index; P=primary endpoint; S=secondary endpoint; E=exploratory endpoint. IR=inadequate response

SPY001 – anti-α4β7 mAb

SPY001 is a highly potent, highly selective, and humanized monoclonal immunoglobulin G1 investigational antibody designed to bind selectively to the α4β7 integrin being developed for the treatment of IBD (UC and CD). The α4β7 integrin is a protein found on the surface of immune cells. This integrin regulates the migration of immune cells to the gut where they contribute to the inflammatory process in IBD. By selectively binding to the α4β7 integrin, SPY001 is designed to prevent the interaction of these immune cells with MAdCAM-1, a molecule expressed on endothelial cells lining the blood vessels in the gut. By blocking the interaction between α4β7 integrin and MAdCAM-1, SPY001 aims to reduce the recruitment of immune cells to the gut, leading to a decrease in inflammation. Since it specifically targets the gut immune system, SPY001 is designed to minimize systemic immunosuppressive effects unrelated to IBD pathology.

SPY001 demonstrates similar potency and selectivity as synthesized vedolizumab in preclinical in vitro models including surface plasmon residence and cellular adhesion assays. We initiated a first-in-human (“FIH”) Phase 1 trial for SPY001 in June 2024. The SPY001 Phase 1 trial was a double blind, placebo-controlled trial in healthy volunteers consisting of a single-ascending dose (“SAD”) component and a multi-ascending dose

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(“MAD”) component. The trial enrolled 56 healthy adult participants into five SAD cohorts and two MAD cohorts in the main portion of the trial. The primary endpoint was safety, with PK and anti-drug antibodies (“ADA”) serving as secondary endpoints. Additional cohorts were added to the trial to evaluate PK in healthy volunteers of various ethnicities to facilitate subsequent global clinical trials. The Phase 1 study is now complete.

Interim results were initially presented in November 2024, with additional data presented in May 2025 with up to eight months of follow up. To date, SPY001 has demonstrated a favorable safety profile across all dose groups, a meaningfully differentiated PK profile supporting potential quarterly or twice annual maintenance dosing, and rapid, complete saturation of α4β7 receptors beyond six months with a single dose of 600mg. Based on these results, SPY001 was advanced into the SKYLINE Phase 2 platform clinical trial.

Initial topline induction results from Part A of the SKYLINE trial in ulcerative colitis subjects were presented in April 2026. 43 subjects were dosed with SPY001 and 41 subjects completed the induction period. Baseline characteristics were consistent with expectations (Figure 4). SPY001 was well tolerated with a safety profile consistent with the α4β7 class. There were six subjects with treatment-emergent adverse events (TEAEs) during the induction treatment period, with one serious adverse event (SAE), deemed not drug-related. The most common AE (occurring in ≥ 2 subjects) was back pain (n=2) (Figure 5). SPY001 achieved the primary endpoint, demonstrating a statistically significant reduction in the RHI score of 9.2 points (p0.0001). Rates of key secondary endpoints of clinical remission and endoscopic improvement were clinically meaningful at 40% and 51%, respectively (Figure 6).

Figure 4. SPY001 disposition and baseline demographics from SKYLINE Part A Induction Topline

1Two subjects withdrew consent.

Figure 5. SPY001 safety summary from SKYLINE Part A Induction Topline

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*Chest pain in a 68-year-old male with history of coronary artery disease and angina pectoris, type 2 diabetes mellitus, hypertension, and hypercholesterolemia who presented with chest pain. ECG and cardiac enzymes did not show signs of a myocardial infarction.

Figure 6. SPY001 efficacy summary from SKYLINE Part A Induction Topline

Primary endpoint of ΔRHI was analyzed using per protocol analysis set  and t-test was applied to test against the null hypothesis of ΔRHI =0 (N=41); Secondary endpoints including Clinical Remission and Endoscopic Improvement rates were analyzed using full analysis set (N=43).

SPY002 and SPY072 – anti-TL1A mAbs

For our anti-TL1A program, we nominated two highly potent, highly selective, and fully human mAb candidates designed to bind to tumor necrosis factor-like ligand 1A (“TL1A”). SPY002 (formerly SPY002-091) is being developed for the treatment of IBD (UC and CD) and SPY072 (formerly SPY002-072) is being developed for the treatment of RD.

TL1A is a protein that plays a role in regulating the immune system and is elevated in gut tissue of individuals with IBD and serum or synovial tissue of individuals with RA, PsA, and axSpA. TL1A interacts with its receptor, death receptor 3 (“DR3”), which is expressed in various immune cells, including T cells and fibroblast-like synoviocytes. This interaction triggers signaling pathways that contribute to inflammation and joint injury in RD, leading to symptomology, such as pain and swelling. SPY002 and SPY072 have been designed to block the interaction between TL1A and DR3, and thereby inhibit the downstream signaling events to dampen the inflammatory response. By neutralizing TL1A, we believe that SPY002 and SPY072 have the potential to modulate the immune response in IBD and rheumatic disease patients, potentially reducing disease activity.

SPY002 and SPY072 bind and inhibit TL1A with subnanomolar potency in preclinical cellular assays. We initiated FIH Phase 1 trials for SPY002 and SPY072 in the fourth quarter of 2024. The Phase 1 trials were each double blind, placebo-controlled evaluations in healthy volunteers, consisting of five SAD cohorts. Each trial enrolled 40 healthy adult participants across the five SAD cohorts in the main portion of the trial. The primary endpoint is safety, with PK and ADAs serving as secondary endpoints, and PD markers as exploratory endpoints. Phase 1 trial enrollment is complete.

Phase 1 data were presented in June 2025 and October 2025, with up to 24-weeks of follow up. To date

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Latest 10-K MD&A

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2026-02-19. Report date: 2025-12-31.

ITEM 7.  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 financial statements and related notes appearing in this Annual Report. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the “Risk Factors” section of this Annual Report, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. As used in this report, unless the context suggests otherwise, “we”, “us”, “our”, “the Company,” “Aeglea BioTherapeutics, Inc.” or “Spyre” refers to Spyre Therapeutics, Inc. and its consolidated subsidiaries taken as a whole.

Acquisition of Pre-Merger Spyre

On June 22, 2023, we acquired Pre-Merger Spyre pursuant to that certain Agreement and Plan of Merger (the “Acquisition Agreement”), dated June 22, 2023, by and among us, Aspen Merger Sub I, Inc., a Delaware corporation and a wholly owned subsidiary of the Company, Sequoia Merger Sub II, LLC, a Delaware limited liability company and one of our wholly owned subsidiaries, and Pre-Merger Spyre. Pre-Merger Spyre was a pre-clinical stage biotechnology company that was incorporated on April 28, 2023 under the direction of Peter Harwin, a Managing Member of Fairmount, for the purpose of holding rights to certain intellectual property being developed by Paragon. Fairmount is a founder of Paragon.

Through the Asset Acquisition, we received the option to license certain intellectual property rights related to four research programs (collectively, the "Option"). On July 12, 2023, we exercised the Option with respect to one of these research programs to be granted an exclusive license to all of Paragon's rights, title and interest in and to intellectual property rights, including inventions, patents, sequence information and results, under SPY001, our α4β7 integrin program, to develop and commercialize antibodies and products worldwide in all therapeutics disorders. On December 14, 2023, we exercised the Option under the Paragon Agreement to be granted an exclusive license to all of Paragon’s rights, title and interest in and to intellectual property rights, including inventions, patents, sequence information and results, under SPY002, our TL1A program, to develop and commercialize antibodies and products worldwide in all therapeutics disorders. On June 5, 2024, we exercised the Option under the Paragon Agreement to be granted an exclusive license to all of Paragon’s rights, title and interest in and to intellectual property rights, including inventions, patents, sequence information and results, under SPY003, our IL-23 program, to develop and commercialize antibodies and products worldwide solely in inflammatory bowel disease ("IBD") indications. The License Agreements pertaining to SPY001 and SPY002 between the Company and Paragon were executed in the second quarter of 2024, and the License Agreement pertaining to SPY003 was executed in October 2024 and subsequently amended and restated on February 24, 2025. Furthermore, as of the date of this Annual Report, the Option remains unexercised with respect to the intellectual property rights related to the last remaining research program under the Paragon Agreement. See discussion in Part I, Item 1 “Business - Intellectual Property” for further discussion of our intellectual property.

Overview

Following the Asset Acquisition, we have significantly reshaped the business into a clinical stage biotechnology company focused on developing next generation therapeutics for patients living with IBD, including ulcerative colitis ("UC") and Crohn's disease ("CD"), and other immune-mediated diseases. Our portfolio of novel and proprietary monoclonal antibody product candidates has the potential to address unmet needs in IBD and RD care by improving efficacy, safety, and/or dosing convenience relative to products currently available or product candidates in development. We have engineered our product candidates with the aim to bind potently and selectively to their target epitopes and to exhibit extended pharmacokinetic half-lives through modifications in the Fc domain, which modifications are designed to increase affinity to human FcRn and increase antibody recycling. We anticipate that half-life extension will enable less frequent administration as compared to marketed or development-stage mAbs that do not incorporate half-life extension modifications. In addition to the development of our product candidates as potential monotherapies, we plan to investigate combinations of our proprietary antibodies in nonclinical studies and clinical trials in order to evaluate whether combination therapy (co-administration or co-formulation of multiple monoclonal antibodies) can lead to greater

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efficacy, as compared to monotherapies in IBD. We intend to deliver our product candidates through convenient, infrequently self-administered, subcutaneous maintenance injections, although the specific delivery mechanism or technology has not been selected given our early stage.

Business and Macroeconomic Conditions

The extent of the impact of macroeconomic events and conditions, including inflation, increasing interest rates, increasing financial market volatility and uncertainty, the impacts of geopolitical instabilities and government actions, including the ongoing military conflict in Ukraine, conflict between Israel and various other parties, recent events in Venezuela, geopolitical tensions between China and the United States, and the implementation of tariffs, sanctions, export or import controls, and other measures that restrict international trade by the United States, China or other governments, and their potential supply chain impact, and public health pandemics on our operational and financial performance will continue to depend on certain developments, including the impact on our clinical studies, employee or industry events, and effect on our suppliers and manufacturers, all of which are uncertain and cannot be predicted. Adverse effects of these large macroeconomic conditions have been prevalent in many of the areas where we, our clinical research organizations ("CROs"), suppliers or third-party business partners conduct business and as a result, we may experience disruptions in our operations. We have experienced and may in the future experience such disruption or delays due to these factors as well as delays due to labor shortages and supply chain disruptions in distribution of clinical trial materials, trial monitoring and data analysis that could materially adversely impact our business, results of operations and overall financial performance in future periods. As of the filing date of this Annual Report, the extent to which these macroeconomic events and conditions may impact our financial condition, results of operations or guidance is uncertain. The effect of these macroeconomic events and conditions may not be fully reflected in our results of operations and overall financial performance until future periods. See Part I, Item 1A “Risk Factors” for further discussion of the possible impact of these macroeconomic conditions on our business.

Components of Operating Results

Revenue

We have recognized license and development revenue from the Immedica Agreement (as defined below) related to our legacy product candidate pegzilarginase. On July 27, 2023, we announced that we entered into an agreement to sell the global rights to pegzilarginase to Immedica. The sale of pegzilarginase to Immedica superseded and terminated the Immedica Agreement.

We have not generated any revenue from commercial product sales. Our ability to generate product revenues in the future will depend on the successful development, regulatory approval, and commercialization of our product candidates.

Licensing and Sale of Pegzilarginase

In March 2021, we licensed to Immedica the rights to the commercialization of pegzilarginase in the European Economic Area, United Kingdom, Switzerland, Andorra, Monaco, San Marino, Vatican City, Turkey, Saudi Arabia, United Arab Emirates, Qatar, Kuwait, Bahrain, and Oman (the "Immedica Agreement"). The Immedica Agreement included a non-refundable upfront payment of $21.5 million from Immedica and up to $3.0 million of payments for development services provided to Immedica. Under the terms of the Immedica Agreement, we were eligible to receive additional regulatory and commercial milestone payments and were entitled to receive royalties in the mid-20% range on net sales of the product in countries included in the Immedica Agreement.

For the year ended December 31, 2023, we recognized revenue of $0.9 million under the Immedica Agreement. The total revenue generated during the year ended December 31, 2023 was attributable to the PEACE Phase 3 trial and PIP trials, drug supply, and royalties from an early access program in France.

On July 27, 2023, we announced that we entered into an agreement to sell the global rights to pegzilarginase to Immedica for $15.0 million in upfront cash proceeds and up to $100.0 million in contingent milestone payments. The sale of pegzilarginase to Immedica superseded and terminated the Immedica

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Agreement. On July 27, 2023, the carrying value of the asset was zero as it was internally developed. Accordingly, we recognized a $16.4 million gain within Gain on sale of in-process research and development, which is comprised of $15.0 million in upfront cash proceeds and the reimbursement of $1.8 million in pre-paid manufacturing costs that was contingent upon a favorable opinion being received by the CHMP, net of transaction costs and the derecognition of pegzilarginase related nonfinancial assets and liabilities totaling $0.4 million.

The milestone payments are contingent on formal reimbursement decisions by national authorities in key European markets and pegzilarginase approval by the FDA, among other events. Subject to the terms 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, the upfront payment and contingent milestone payments actually received by us during the CVR term, net of expenses and adjustments, will be distributed to holders of our CVRs (as defined below) pursuant to the CVR Agreement.

During the twelve months ended December 31, 2025, the Company recognized a gain of $10.0 million within Gain on Sale of in-process research and development, for achieving certain reimbursement decision milestones during the period. As of December 31, 2025, $3.0 million remains outstanding and reflected in Prepaid expenses and other current assets. There was no similar gain during the twelve months ended December 31, 2024 nor similar receivable as of December 31, 2024.

Milestone payments, net of allowable expenses and adjustments, will be distributed to CVR holders pursuant to the CVR agreement resulting from the Asset Acquisition and will reduce the CVR liability.

Research and development expenses

Research and development expenses consist primarily of costs incurred for the discovery and development of our product candidates, historically including pegtarviliase and pegzilarginase, and now focused on our portfolio of product candidates for IBD and other immune-mediated diseases. We contract with external providers for nonclinical studies and clinical trials. Our research and development expenses include:

•costs from acquiring clinical trial materials and services performed for contracted services with contract manufacturing organizations, or CMOs;

•fees paid to clinical trial sites, CROs, CMOs, nonclinical research companies, and academic institutions;

•direct and pass through costs associated with research conducted under the Paragon Agreement; and

•employee and consultant-related expenses incurred, which include salaries, benefits, travel, and stock-based compensation.

Research and development costs are expensed as incurred. Advance payments for goods or services to be rendered in the future for use in research and development activities are deferred and capitalized. The capitalized amounts are expensed as the related goods are delivered or the services are performed.

Research and development expenses have historically represented the largest component of our total operating expenses.

Our expenditures on current and future nonclinical and clinical development programs are subject to numerous uncertainties in timing and cost to completion. The duration, costs, and timing of nonclinical activities, clinical trials, and development of our product candidates will depend on a variety of factors, including:

•the scope, rate of progress, and expenses of our ongoing research activities as well as any additional nonclinical activities, clinical trials, and other research and development activities;

•future clinical trial results;

•uncertainties in clinical trial enrollment rates or drop-out or discontinuation rates of patients;

•changes in the competitive drug development environment;

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•potential safety monitoring or other studies requested by regulatory agencies;

•significant and changing government regulation;

•the timing and receipt of regulatory approvals, if any; and

•macroeconomic events and conditions, including inflation, increasing interest rates, increasing financial market volatility and uncertainty, the impact of geopolitical instabilities and government actions, including ongoing military conflict in Ukraine, conflict in Israel and surrounding areas, recent events in Venezuela, geopolitical tensions between China and the United States, and the implementation of tariffs, sanctions, export or import controls, and other measures that restrict international trade by the United States, China or other governments, and its potential supply chain impact, and public health pandemics.

The process of conducting the necessary clinical research to obtain FDA and other regulatory approval is costly and time-consuming and the successful development of our product candidates is highly uncertain. The risks and uncertainties associated with our research and development projects are discussed more fully in Part I, Item 1A of this Annual Report titled “Risk Factors.” As a result of these risks and uncertainties, we are unable to determine with any degree of certainty the duration and completion costs of our research and development projects, or if, when, or to what extent we will generate revenues from the commercialization and sale of any of our product candidates that obtain regulatory approval. We may never succeed in achieving regulatory approval for any of our product candidates.

General and administrative expenses

General and administrative expenses consist primarily of salaries and other related costs, including stock-based compensation, for personnel in executive, finance, accounting, legal, corporate development, information technology, and human resources functions. Other significant costs include legal fees relating to corporate matters and fees for insurance, accounting, consulting, facilities, and recruiting services.

We expect that our general and administrative expenses will increase in the future to support our continued research and development activities. These increases will likely include higher costs related to the hiring of additional personnel and fees to outside consultants, lawyers and accountants, among other expenses. Additionally, we have incurred and expect to continue to incur increased costs associated with being a public company, including expenses related to services associated with maintaining compliance with Nasdaq listing rules and SEC requirements, insurance, and investor relations costs.

Restructuring

On April 12, 2023, based on the review of the inconclusive interim results from our Phase 1/2 clinical trial of pegtarviliase for the treatment of classical homocystinuria and other business considerations, we announced that we had initiated a process to explore strategic alternatives to maximize stockholder value and engaged an independent exclusive financial advisor to support this process. As a result, we implemented a restructuring plan that resulted in an approximate 83% reduction of our existing headcount by June 30, 2023.

All charges related to the restructuring activities were recognized during the year ended December 31, 2023. No further restructuring charges will be incurred under the restructuring plan.

Severance and Stock Compensation

We recognized restructuring expenses consisting of cash severance payments and other employee-related costs of $6.4 million during the year ended December 31, 2023. Cash payments for employee related restructuring charges of $1.1 million and $5.3 million were paid during December 31, 2024 and 2023, respectively. In addition, we recognized $1.0 million in non-cash stock-based compensation expense related to the accelerated vesting of stock-based awards for certain employees. We recorded these restructuring charges based on each employee’s role to the respective research and development and general and administrative operating expense categories on its consolidated statements of operations and comprehensive loss.

Sale of Assets

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During the second quarter of 2023, we sold various lab equipment, consumables, and furniture and fixtures for total consideration of $0.5 million. After recording the disposal of all our property and equipment net of proceeds, we recorded a $0.7 million and $0.2 million loss on disposal of long-lived assets which is included in Research and development and General and administrative expenses, respectively.

Lease Right-of-use Asset and Leasehold Improvement Impairment

Effective June 30, 2023, we abandoned our leased office space in Austin, Texas. As a result, we recognized an impairment loss of $0.9 million related to the operating lease right-of-use asset and $1.7 million related to leasehold improvements. On August 7, 2023, we terminated our building lease in Austin, Texas. The negotiated termination agreement obligated us to pay the lessor a $2.0 million termination fee in exchange for releasing us of all further obligations under the lease. All charges related to the restructuring activities were recognized during the second quarter of 2023. No further restructuring charges will be incurred under the restructuring plan.

Interest income

Interest income consists of interest earned on our cash, cash equivalents, marketable securities, and restricted cash.

Income taxes

During the year ended December 31, 2024, we completed the merger of our nine U.S. subsidiaries (the "Former Subsidiaries") with and into our parent company, Spyre Therapeutics, Inc. In addition, we dissolved our subsidiaries in the United Kingdom and Ireland in 2026 and 2025, respectively, both of which had not had any operational activity since the closing of the Asset Acquisition. We filed a consolidated U.S. corporate federal income tax return for the 2024 tax year for us and our Former Subsidiaries.

Our income tax returns are subject to audit and adjustment by the taxing authorities. We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the financial statements and the tax bases of assets and liabilities. A valuation allowance is established against the deferred tax assets to reduce their carrying value to an amount that is more likely than not to be realized. The deferred tax assets and liabilities are classified as noncurrent along with the related valuation allowance. Due to our lack of earnings history, the net deferred tax assets have been fully offset by a valuation allowance.

We recognize benefits of uncertain tax positions if it is more likely than not that such positions will be sustained upon examination based solely on the technical merits, as the largest amount of benefits that is more likely than not to be realized upon the ultimate settlement. Our policy is to recognize interest and penalties related to the unrecognized tax benefits as a component of income tax expense.

Critical Accounting Policies and Estimates

Our consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States ("U.S. GAAP"). The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, costs and expenses, and related disclosures. These estimates form the basis for judgments we make about the carrying values of our assets, liabilities and equity and the amount of revenues and expenses, which are not readily apparent from other sources. We base our estimates on historical experience and on various other assumptions that we believe are reasonable under the circumstances. On an ongoing basis, we evaluate our estimates and assumptions. Our actual results may differ materially from these estimates under different assumptions or conditions.

Our critical accounting policies are those policies which require the most significant judgments and estimates in the preparation of our consolidated financial statements. The most significant estimates and assumptions that management considers in the preparation of our financial statements relate to accrued research and development costs; the valuation of consideration transferred in acquiring in-process research and development ("IPR&D"); the discount rate, probabilities of success, and timing of estimated cash flows in

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the valuation of the CVR liability; inputs used in the Black-Scholes model for stock-based compensation expense; estimated future cash flows used in calculating the impairment of right-of-use lease assets; and estimated cost to complete performance obligations related to revenue recognition. The consideration transferred in acquiring IPR&D in connection with the acquisition of Pre-Merger Spyre was comprised of our common stock and shares of Series A Preferred Stock. To determine the fair value of the equity transferred, we considered the per share value of our PIPE financing that closed in June 2023 (the "June 2023 PIPE"), which was a financing involving a group of accredited investors.

We define our critical accounting policies as those accounting principles generally accepted in the United States that require us to make subjective estimates and judgments about matters that are uncertain and are likely to have a material impact on our financial condition and results of operations, as well as the specific manner in which we apply those principles. Our significant accounting policies are more fully described in Note 2 to our consolidated financial statements included elsewhere in this Annual Report.

Revenue recognition

We enter into license agreements related to our technologies that we have determined are within the scope of Accounting Standards Codification 606. Based on the terms and conditions of our agreements, we identify the goods and services that we promise to transfer to the customer, which may consist of the licensing of technologies, the performance of research and development activities, and/or the supply of products related to our technologies. Based on the nature of the goods and services provided and the customer’s intended benefit of the arrangement, we evaluate which of the promised goods and services are distinct and, therefore, represent a performance obligation, which may require us to combine certain promised goods and services that are determined to not be distinct from one another. We also evaluate whether an agreement provides the customer an option to purchase future goods or services at a discounted price, or a material right, which would also represent a performance obligation.

In exchange for the performance obligations, we estimate the amount of consideration promised by the customer, or transaction price, which may include both fixed and variable consideration. Variable consideration, which may consist of various milestone payments based upon the achievement of certain events or conditions, sales-based royalties, or payments contingent on the performance of research and development services, are included in the transaction price only if we expect to receive such consideration and determine it is likely that the inclusion of the variable consideration will not result in a significant reversal in the cumulative amount of revenue recognized under the arrangement. Sales-based royalty and milestone payments that we determine are predominantly related to the license of our intellectual property are excluded from the transaction price we expect to receive until the underlying sales occur.

We allocate the estimated transaction price to the identified performance obligations based on the relative estimated stand-alone selling price ("SSP") of each performance. SSP is based on the observable price of our goods and services, or when SSP is not directly observable, we estimate SSP based on factors such as forecasted revenues or costs, development timelines, discount rates, probabilities of technical and regulatory success, and considerations such as market conditions and entity-specific factors. We recognize revenue allocated to each performance obligation either at a point-in-time or over time in a manner that depicts the transfer of control of the promised goods and services to the customer. For performance obligations that are recognized over time, we estimate the measure of progress associated with the satisfaction of the performance obligation based on an input or output method, which may be based on factors such as costs incurred, labor hours expended, time elapsed, among other measures based on the nature of the performance obligation. The estimates made on an input or output method are subject to change and may result in material changes to revenue that could materially affect our results of operations. Please refer to Note 13, Strategic License Agreements, to the consolidated financial statements included elsewhere in this Annual Report.

Accrued research and development costs

We record the costs associated with research and development such as nonclinical studies, clinical trials, and manufacturing as incurred. These costs are a significant component of our research and development expenses, with a substantial portion of our on-going research and development activities conducted by third-party service providers, including CROs, CMOs, and our related-party Paragon.

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We accrue for expenses resulting from obligations under the Paragon Agreement and agreements with CROs, CMOs, and other outside service providers for which payment flows do not match the periods over which materials or services are provided to us. We record accruals based on estimates of services received and efforts expended pursuant to agreements established with Paragon, CROs, CMOs, and other outside service providers. These estimates are typically based on contracted amounts applied to the proportion of work performed and determined through analysis with internal personnel and external service providers as to the progress or stage of completion of the services. We make significant judgments and estimates in determining the accrual balance in each reporting period. In the event advance payments are made to Paragon, a CRO, a CMO, or an outside service provider, the payments will be recorded as a prepaid asset which will be amortized as the contracted services are performed. As actual costs become known, we adjust our accruals. Inputs, such as the services performed, the number of patients enrolled, or the trial duration, may vary from our estimates, resulting in adjustments to research and development expense in future periods. Changes in these estimates that result in material changes to our accruals could materially affect our results of operations. However, there have been no material changes in estimates for the periods presented.

License Agreements Contingent Milestone Payments

The Company’s license agreements include specific development, regulatory, and clinical milestone payments that are payable upon the resolution of a contingency, such as upon the selection of a development candidate, first dosing of a human patient in clinical trials or receipt of the Food and Drug Administration’s (“FDA”) approval of a Spyre drug. The achievement of these milestone payments involves many factors outside of the Company’s control and therefore the associated likelihood can therefore not be considered probable until the related contingency is resolved. Based on the preceding, the Company accrues each milestone payment upon the achievement of the applicable milestone event.

Impairment of ROU Assets and Leasehold Improvements

We are required to test for impairment of our long-lived assets when events arise that would call into question the recoverability of an asset group. We determined that the abandonment of our leased office space in Austin, Texas would meet this criteria. Accordingly, we tested for impairment using a discounted future cash flow model using estimated cash flows that could be obtained through a hypothetical sub-letting of the leased space.

Convertible Preferred Stock Issued through PIPE

The Company records shares of convertible preferred stock at their respective fair values on the dates of issuance, net of issuance costs. The Company classified the Series B Preferred Stock outside of stockholders’ equity at issuance because if conversion to common stock was not approved by the stockholders, the Series B Preferred Stock was redeemable at the option of the holders for cash equal to the closing price of the Company's common stock on the last trading day prior to the holder’s redemption request. The Company determined that the conversion and redemption was outside of the Company’s control. Additionally, the Company determined the Series B Preferred Stock did not contain any embedded derivatives and therefore the conversion and redemption features did not require bifurcation.

Since the Series B Preferred Stock is no longer redeemable, the associated balances of the Series B Preferred Stock were reclassified from mezzanine equity to permanent equity during the second quarter of 2024.

Contingent Value Rights Liability

On July 3, 2023, we issued contingent value rights ("CVRs") to certain of our securityholders of record as of the close of business on that date (the "Legacy Stockholders"), but these were not issued to holders of shares of common stock or preferred stock issued to former stockholders of Pre-Merger Spyre or the investors (the "June 2023 Investors") in the June 2023 PIPE. Each CVR entitles the holder thereof 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 certain legacy assets owned by us prior to the Asset Acquisition (the "Legacy Assets"). Certain contingent payments under the CVR Agreement qualify as derivatives under ASC 815, Derivatives and Hedging, and are recorded as a liability on the balance sheet as of December 31, 2025

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and December 31, 2024. The CVR liability is considered a Level 3 instrument that is initially measured at its estimated fair value on the transaction date and subsequently remeasured at each reporting date with changes recorded in the consolidated statement of operations. The determination of the initial and subsequent fair value of the CVR liability requires significant judgment by management. Changes in any of the inputs not related to facts and circumstances existing as of the transaction date may result in a significant fair value adjustment, which can impact the results of operations in the period in which the adjustment is made. For example, changes in inputs related to the likelihood of regulatory approval increases or decreases as the regulatory approval process progresses and decisions or comments are issued by the applicable regulatory agencies.

Recently Issued Accounting Pronouncements

Information regarding recent accounting pronouncements is included in Item 8 of Part II, "Financial Statements and Supplementary Data", Note 2 in the "Notes to Consolidated Financial Statements" of this Annual Report.

Results of Operations

A discussion and analysis of our financial condition and results of operations for the year ended December 31, 2025 compared to the year ended December 31, 2024 and a discussion and analysis of our financial condition and results of operations for the year ended December 31, 2024 compared with the year ended December 31, 2023 is presented below.

Comparison of the Years Ended December 31, 2025 and 2024

The following table summarizes our results of operations for the years ended December 31, 2025 and 2024, together with the changes in those items in dollars and as a percentage:

Year Ended December 31,

Dollar Change

% Change

2025

2024

(in thousands)

Operating expenses:

Research and development

171,653 

162,790 

8,863 

5

%

General and administrative

47,909 

45,776 

2,133 

5

%

Gain on sale of in-process research and development asset

(10,000)

— 

(10,000)

*

Total operating expenses

209,562 

208,566 

996 

*

Loss from operations

(209,562)

(208,566)

996 

*

Other income (expense):

Interest income

24,885 

21,312 

3,573 

*

Other income (expense), net

29,459 

(20,713)

50,172 

*

Total other income

54,344 

599 

53,745 

*

Loss before income tax expense

(155,218)

(207,967)

(52,749)

*

Income tax benefit (expense)

15 

(51)

66 

*

Net loss

$

(155,203)

$

(208,018)

$

(52,815)

*

___________________________________________

*Percentage not meaningful

Research and development expenses increased by $8.9 million, or 5%, to $171.7 million for the year ended December 31, 2025, from $162.8 million for the year ended December 31, 2024. The increase was primarily driven by increased clinical development activities and higher headcount partially offset by lower early-stage research and development.

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Year Ended December 31,

Dollar Change

% Change

2025

2024

(in thousands)

External research and development expenses:

Preclinical

$

16,016 

$

62,235 

$

(46,219)

(74)

%

IBD

98,290 

64,919 

33,371 

51 

%

Rheumatic diseases

16,552 

— 

16,552 

*

Stock-based compensation (1)

— 

14,459 

(14,459)

(100)

%

Legacy Aeglea assets

194 

(906)

1,100 

121 

%

Total external research and development expense

131,052 

140,707 

(9,655)

(7)

%

Internal research and development expenses:

Compensation

22,893 

11,728 

11,165 

95%

Stock-based compensation

16,270 

9,112 

7,158 

79%

Other

1,438 

1,243 

195 

16 

%

Total internal research and development expenses

40,601 

22,083 

18,518 

84 

%

Total research and development expense

$

171,653 

$

162,790 

$

8,863 

5 

%

(1) For the year ended December 31, 2024, $14.5 million was recognized as stock compensation expense related to the Parapyre Option Obligation. There was no similar expense for the year ended December 31, 2025.

External research and development expenses include costs associated with third parties contracted to conduct research and development activities on behalf of the Company, including through Paragon, CROs, CMOs, and third-party laboratories. For the year ended December 31, 2025 and 2024, external research and development costs accounted for $131.1 million and $140.7 million, respectively. Preclinical expenses decreased primarily due to a reduction in early-stage research and development activities given our pipeline's advancement coupled with lower intellectual property license and sub-licensing fees. IBD expenses increased primarily due to increases in clinical development costs related to ongoing or planned clinical trials. Rheumatic diseases costs increased due to increases in manufacturing, clinical development costs, and intellectual property licensing and sub-licensing fees. External stock-based compensation decreased due to our obligations ending under the Parapyre Option Obligation.

Internal research and development expenses include compensation and related costs associated with our research and development employees. For the year ended December 31, 2025 and 2024, internal research and development costs accounted for $40.6 million and $22.1 million, respectively. The increase was primarily driven by an increase in research and development headcount.

General and Administrative Expenses. General and administrative expenses increased by $2.1 million, or 5%, to $47.9 million for the year ended December 31, 2025, from $45.8 million for the year ended December 31, 2024. The increase was primarily attributable to an increase in compensation costs due to an increase in general and administrative headcount.

Gain on Sale of In-Process Research and Development Asset. During the year ended December 31, 2025, the Company recognized a gain of $10.0 million for an achieved milestone related to the 2023 sale of the global rights of the legacy Aeglea asset pegzilarginase to Immedica, driven by a favorable reimbursement decision for pegzilarginase in Europe. There was no similar gain or loss during the year ended December 31, 2024.

Interest Income. Interest income was $24.9 million and $21.3 million for the year ended December 31, 2025 and 2024, respectively. The increase was primarily due to higher investment balances.

Other income, net. Other income, net for the year ended December 31, 2025 increased by $50.2 million versus the year ended December 31, 2024 primarily driven by changes in the fair value of the CVR liability,

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which was primarily driven by changes in the likelihood of achievement of certain milestones and receipt of certain cash consideration within the CVR term, changes in estimated reimbursement rates compared to reimbursement target rates, changes in estimated cash flow dates, and an increase in risk-adjusted discount rates, partially offset by time value of money adjustments.

Comparison of the Years Ended December 31, 2024 and 2023

The following table summarizes our results of operations for the years ended December 31, 2024 and 2023, together with the changes in those items in dollars and as a percentage:

Year Ended December 31,

Dollar Change

% Change

2024

2023

(in thousands)

Revenue:

Development fee and royalty

— 

886 

(886)

(100

%)

Total revenue

— 

886 

(886)

Operating expenses:

Research and development

162,790 

89,504 

73,286 

82

%

General and administrative

45,776 

39,946 

5,830 

15

%

Acquired in-process research and development

— 

130,188 

(130,188)

*

Gain on sale of in-process research and development asset

— 

(16,449)

16,449 

*

Total operating expenses

208,566 

243,189 

(34,623)

*

Loss from operations

(208,566)

(242,303)

(33,737)

*

Other income (expense):

Interest income

21,312 

6,147 

15,165 

*

Change in fair value of forward contract liability

— 

(83,530)

83,530 

*

Other expense, net

(20,713)

(19,130)

(1,583)

*

Total other income (expense)

599 

(96,513)

97,112 

*

Loss before income tax expense

(207,967)

(338,816)

(130,849)

*

Income tax (expense) benefit

(51)

26 

(77)

*

Net loss

$

(208,018)

$

(338,790)

$

(130,772)

*

___________________________________________

*Percentage not meaningful

Development Fee and Royalty Revenue. For the year ended December 31, 2024, we did not recognize any revenue in connection with the Immedica Agreement. For the year ended December 31, 2023, we recognized $0.9 million of development fee revenue in connection with the Immedica Agreement. The revenue generated during the year ended December 31, 2023, was attributable to the PEACE Phase 3 trial and drug supply and royalties from an early access program in France.

Research and development expenses increased by $73.3 million, or 82%, to $162.8 million for the year ended December 31, 2024, from $89.5 million for the year ended December 31, 2023. The increase was primarily driven by higher early-stage research and development and increased compensation costs partially offset by decrease in costs related to the Company's legacy rare disease pipeline.

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Year Ended December 31,

Dollar Change

% Change

2024

2023

(in thousands)

External research and development expenses:

Preclinical

$

62,235 

$

37,130 

$

25,105 

68 

%

IBD

64,919 

6,017 

58,902 

979 

%

Stock-based compensation (1)

14,459 

11,328 

3,131 

28 

%

Legacy Aeglea assets

(906)

18,187 

(19,093)

(105)

%

Total external research and development expense

140,707 

72,662 

68,045 

94 

%

— 

Internal research and development expenses:

— 

Compensation

11,728 

6,801 

4,927 

72%

Stock-based compensation

9,112 

2,910 

6,202 

213%

Other

1,243 

7,131 

(5,888)

(83)

%

Total internal research and development expenses

22,083 

16,842 

5,241 

31 

%

Total research and development expense

$

162,790 

$

89,504 

$

73,286 

82 

%

(1) For the years ended December 31, 2024 and 2023, $14.5 million and $11.4 million was recognized as stock compensation expense related to the Parapyre Option Obligation, respectively.

External research and development expenses include costs associated with third parties contracted to conduct research and development activities on behalf of the Company, including through Paragon, CROs, CMOs, and third-party laboratories. For the year ended December 31, 2024 and 2023, external research and development costs accounted for $140.7 million and $72.7 million, respectively. The increase was primarily due to increased costs associated with our IBD pipeline candidates, including preclinical and manufacturing activities coupled with intellectual property license fees, and stock compensation expense related to the Parapyre Option Obligation, partially offset by decreased costs related to the Company's legacy rare disease pipeline.

Internal research and development expenses include compensation and related costs associated with our research and development employees, as well as costs associated with the Company's on-premises research laboratory. For the year ended December 31, 2024 and 2023, internal research and development costs accounted for $22.1 million and $16.8 million, respectively. The increase was primarily driven by an increase in research and development headcount, partially offset by a decrease in costs associated with our on-premises research laboratory that was decommissioned, including the elimination of related internal roles, in the first half of 2023.

General and Administrative Expenses. General and administrative expenses increased by $5.8 million, or 15%, to $45.8 million for the year ended December 31, 2024, from $39.9 million for the year ended December 31, 2023. The increase was primarily due to an increase in stock-based compensation expense, inclusive of acceleration expense related to legacy Aeglea officers and directors, partially offset by reduction in compensation costs primarily associated with lower legacy severance costs, and reduction in lease termination costs that were incurred in the prior year.

Acquired In-process Research and Development Expenses. Acquired IPR&D expenses were $130.2 million for the year ended December 31, 2023, as the acquisition of Pre-Merger Spyre was determined by management to be an asset acquisition, in accordance with U.S. GAAP as the product candidates were determined to have no alternative future use. There was no similar expense during the year ended December 31, 2024.

Gain on Sale of In-Process Research and Development Asset. Gain on sale of in-process research and development asset during the year ended December 31, 2023 was driven by the sale of pegzilarginase to Immedica. There was no similar gain or loss during the year ended December 31, 2024.

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Interest Income. Interest income was $21.3 million and $6.1 million for the twelve months ended December 31, 2024 and 2023, respectively. The increase was primarily due to higher investment balances.

Change in Fair Value of Forward Contract Liability. Non-cash expenses associated with the change in fair value of the forward contract liability were $83.5 million for the year ended December 31, 2023. This expense was due to the change in fair value of the underlying Series A Preferred Stock between June 22, 2023 and the forward contract's settlement on July 7, 2023. There was no similar expense during the year ended December 31, 2024.

Other expense, net. Other expense, net for the year ended December 31, 2024 increased by $1.6 million versus the year ended December 31, 2023, primarily driven by changes in the fair value of the CVR liability.

Liquidity and Capital Resources

We are a clinical stage biotechnology company with a limited operating history, and due to our significant research and development expenditures, we have generated operating losses since our inception and have not generated any revenue from the 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 our inception and through December 31, 2025, we have funded our operations by raising an aggregate of approximately $1.6 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 our product rights for commercialization of pegzilarginase in Europe and certain countries in the Middle East. As of December 31, 2025, we had an accumulated deficit of $1.1 billion.

Our primary use of cash is to fund the development of our product candidates and advance our pipeline. This includes both the research and development costs and the general and administrative expenses required to support those operations. We have incurred significant operating losses since our inception and we anticipate such losses, in absolute dollar terms, to increase as we continue clinical development of our product candidates, prepare for the potential commercialization of our product candidates, and expand our development efforts in our pipeline of nonclinical candidates. Based on current operating plans, we have sufficient resources to fund operations for at least one year from the issuance date of the financial statements included in this Annual Report with existing cash, cash equivalents, and marketable securities. We 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 we are unable to obtain additional financing or generate license or product revenue, the lack of liquidity could have a material adverse effect on us.

Recent sources of liquidity

In June 2023, we sold 721,452 shares of convertible Series A preferred stock at $291.08 per share in a private placement offering for net proceeds of $197.3 million after deducting approximately $12.7 million of placement agent and other offering expenses.

In December 2023, we sold 6,000,000 shares of our common stock at an offering price of $15.00 and 150,000 shares of convertible Series B preferred stock at $600.00 per share for net proceeds of $169.1 million after deducting approximately $10.9 million of placement agent and other offering expenses.

In March 2024, we completed a private placement of 121,625 shares of Series B Preferred Stock at $1,480 per share resulting in net proceeds of approximately $168.9 million after deducting approximately $11.2 million of placement agent and other offering costs.

In November 2024, we sold 8,366,250 shares of our common stock in an underwritten public offering, inclusive of 1,091,250 shares pursuant to the full exercise of an over-allotment option, under our shelf registration statement on Form S-3 at a price per share of $27.50, resulting in net proceeds of $215.9 million after deducting approximately $14.2 million of underwriting discounts and other offering costs.

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During the year ended December 31, 2024, we sold an aggregate of 777,432 shares of common stock under an at-the-market offering program at an average price per share of $26.935 resulting in net proceeds of approximately $20.5 million after deducting approximately $0.4 million of sales agent commissions and other offering costs.

In October 2025, we sold 17,094,594 shares of our common stock in an underwritten public offering, inclusive of 2,229,729 shares pursuant to the full exercise of the underwriters' over-allotment option, under our shelf registration statement on Form S-3 at a price per share of $18.50, resulting in net proceeds of $296.4 million after deducting approximately $19.9 million of underwriting discounts and other offering costs.

During the three and twelve months ending December 31, 2025, we sold an aggregate of 445,668 shares of common stock under an at-the-market offering program at an average price per share of $33.772 resulting in net proceeds of $14.8 million, after deducting $0.3 million of sales agent commissions and other offering costs.

The following table summarizes our cash flows for the periods indicated (in thousands):

Year Ended December 31,

2025

2024

Net cash and cash equivalents (used in) provided by:

Operating activities

$

(169,252)

$

(157,410)

Investing activities

(143,475)

(353,285)

Financing activities

309,025 

410,906 

Effect of exchange rate on cash, cash equivalents, and restricted cash

— 

(3)

Net decrease in cash and cash equivalents

$

(3,702)

$

(99,792)

Cash Used in Operating Activities

Cash used in operating activities for the year ended December 31, 2025 was $169.3 million and reflected a net loss of $155.2 million adjusted for a $10.0 million non-operating gain on sale of in-process research and development, a $29.8 million decrease in the fair value of the CVR liability, $8.1 million in net accretion of discount on marketable securities and a $5.9 million change in net operating assets and liabilities driven primarily by timing of payments to vendors, partially offset by share-based compensation expense of $37.6 million.

Cash used in operating activities for the year ended December 31, 2024 was $157.4 million and reflected a net loss of $208.0 million. Our net loss coupled with $11.4 million in net accretion of discount on marketable securities and a $4.5 million net change in operating assets and liabilities and was partially offset by non-cash expenses, including $44.8 million in stock-based compensation and $20.4 million change in fair value of CVR liability. The net change in operating assets and liabilities was primarily driven by timing of payments to vendors.

Cash (Used in) Provided by Investing Activities

Cash used in investing activities for the year ended December 31, 2025 was $143.5 million and primarily consisted of $522.2 million in purchases of marketable securities, $7.0 million in proceeds from the sale of in-process research & development asset partially offset by $371.7 million in maturities and sales of marketable securities.

Cash used in investing activities for the year ended December 31, 2024 was $353.3 million and primarily consisted of $599.3 million in purchases of marketable securities, partially offset by $246.0 million in maturities and sales of marketable securities.

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Cash Provided by Financing Activities

Cash provided by financing activities for the year ended December 31, 2025 was $309.0 million, which primarily consisted of the net proceeds of $296.4 million and $14.8 million from the issuance common stock in the October 2025 follow-on offering and the December 2025 at-the-market offering program, respectively, $3.3 million proceeds from stock option exercises and sales of common stock under our Employee Stock Purchase Plan, partially offset by a $5.3 million payment to CVR holders.

Cash provided by financing activities for the year ended December 31, 2024 was $410.9 million, which primarily consisted of the net proceeds from the issuance of the Series B Preferred Stock in the March 2024 PIPE of $168.9 million, $215.9 million and $20.5 million in net proceeds from the issuance of common stock in connection with the November 2024 Offering and the at-the-market offering program, respectively, and $7.5 million from proceeds from stock option exercises and sales of common stock under our 2016 Employee Stock Purchase Plan and the exercise of pre-funded warrants partially offset by a $1.4 million payment to CVR holders.

Contractual Obligations and Other Commitments

Effective June 30, 2023, we abandoned our leased corporate headquarters and laboratory space located in Austin, Texas. As a result, we recognized an impairment loss related to the operating right-of-use asset of $0.9 million. On August 7, 2023, we terminated our building lease in Austin, Texas. In exchange for releasing us of all further obligations under the lease, we paid the lessor a $2.0 million termination fee.

We have entered into agreements in the normal course of business with CROs for clinical trials and CMOs, and with vendors for nonclinical research studies and other services and products for operating purposes. These contractual obligations are cancelable at any time by us, generally upon 30 to 60 days’ prior written notice to the vendor.

Contingent contractual obligations

Through the Asset Acquisition, we received the Option to license certain intellectual property rights related to certain research programs. The exercise of the Option allows for us to enter into an exclusive license agreement with Paragon for the respective research program. Thus far we have exercised the Option and entered into license agreements with respect to SPY001, SPY002, SPY072 and SPY003. Under the terms of each License Agreement, we are obligated to pay Paragon up to $22.0 million based on specific development, regulatory and clinical milestones for the first product under each agreement. As of December 31, 2025, we have incurred a total of $18.0 million of milestone fees out of a total maximum of $66.0 million in potential milestone fees across all License Agreements. As of December 31, 2025, no milestone fees remain outstanding and payable. With respect to the SPY002 License Agreement only, on a product by product basis, we are obligated to pay sublicensing fees of up to approximately $20.0 million upon the achievement of mostly commercial milestones. As of December 31, 2025, we have incurred $2.6 million of sublicensing fees of which none is outstanding and payable.