Apogee Therapeutics, Inc. (APGE)

CIK: 0001974640. SIC: 2836 Biological Products, (No Diagnostic Substances). Latest 10-K as of: 2026-03-02.

SIC breadcrumb: Manufacturing > Chemicals And Allied Products > SIC 2836 Biological Products, (No Diagnostic Substances)

SEC company page: https://www.sec.gov/edgar/browse/?CIK=1974640. Latest filing source: 0001974640-26-000002.

Selected Fundamentals

Financials

Annual standardized facts from SEC companyfacts as of latest extracted filing date 2026-03-02. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001974640.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 2026-05-11. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001974640.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: 0001193125-26-215698.

Extracted structurally from real Item 2 body heading to real Item 3/4 boundary. Confidence: high. Filing date: 2026-05-11. 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 of our financial condition and results of operations in conjunction with the condensed consolidated financial statements and related notes included elsewhere in this Quarterly Report, as well as our audited consolidated financial statements and the related notes included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”). The following discussion contains forward-looking statements that reflect our current plans, forecasts, estimates and beliefs and involve risks and uncertainties. Our historical results are not necessarily indicative of the results that may be expected for any period in the future. Our actual results, outcomes and the timing of events could differ materially from those discussed in the forward-looking statements. Factors that could cause or contribute to these differences include those discussed below and elsewhere in this Quarterly Report, particularly in the section titled “Special Note Regarding Forward Looking Statements” and “Risk Factors.” We urge you to consider these factors carefully in evaluating the forward-looking statements contained in this Quarterly Report. Forward-looking statements are not historical facts, reflect our current views with respect to future events, and apply only as of the date made. We do not intend, and undertake no obligation, to update these forward-looking statements, except as required by law. Unless the context requires otherwise, references to “we,” “us,” “our,” “Apogee” or “the Company” refer to Apogee Therapeutics, Inc. and its subsidiaries.

This Quarterly Report contains references to our programs, which are used interchangeably to refer to our clinical programs within our pipeline and our products under development.

Overview

We are a clinical stage biotechnology company advancing optimized, novel biologics with the potential for differentiated efficacy and dosing in the largest inflammatory and immunology (“I&I”) markets, including for the treatment of atopic dermatitis (“AD”), asthma, eosinophilic esophagitis (“EoE”), chronic obstructive pulmonary disease (“COPD”), and other I&I indications. Our antibody programs are designed to overcome limitations of existing therapies by targeting well-established mechanisms of action and incorporating advanced antibody engineering to optimize half-life and other properties.

Our pipeline comprises multiple antibody programs being developed initially for the treatment of I&I indications as monotherapies and combinations, including zumilokibart (APG777), APG279 (zumilokibart + APG990), APG273 (zumilokibart + APG333), and APG808 (each a “program” or “product candidate”). With four validated targets in our portfolio, we are seeking to achieve best-in-class efficacy and dosing through monotherapies and combinations of our novel antibodies. Based on a broad pipeline and depth of expertise, we believe we can deliver value and meaningful benefit to patients underserved by today’s standard of care. We believe each of our product candidates has potential for broad application across multiple I&I indications.

Zumilokibart (APG777) – anti-IL13 antibody

Zumilokibart is a subcutaneous (“SQ”) extended half-life monoclonal antibody (“mAb”) targeting IL-13.

Phase 1 Trial in Healthy Volunteers

In August 2023, we initiated a Phase 1 trial of zumilokibart in healthy volunteers. The zumilokibart Phase 1 trial was a double-blind, placebo-controlled study in healthy volunteers and consisted of a single-ascending dose (“SAD”) component and a multiple ascending dose component. Eight healthy volunteers, six treated with zumilokibart and two treated with placebo, were enrolled in each cohort, and we enrolled a total of 40 healthy adult subjects in the trial.

In March 2024, we announced positive interim safety and pharmacokinetic (“PK”) data from this trial with zumilokibart demonstrating a potential best-in-class PK profile, including a half-life of 77 days, supporting the potential for every three- to six- month maintenance dosing in AD. Single doses of zumilokibart demonstrated a deep and sustained effect on pharmacodynamic (“PD”) markers out to approximately 12 months. Zumilokibart was well-tolerated across all dose groups.

APEX Phase 2 Trial for Patients with AD

In May 2024, we announced dosing of our first patient in the APEX Phase 2 clinical trial, which is a randomized, placebo-controlled study evaluating zumilokibart in patients with moderate-to-severe AD.

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In July 2025, we announced positive 16-week data from the Part A portion of the APEX Phase 2 clinical trial. Part A of the trial enrolled 123 adult patients who were randomized 2:1 to zumilokibart versus placebo and received an induction regimen dosing of 720mg at Weeks 0 and 2, followed by 360mg at Weeks 4 and 12. The primary endpoint for the induction arm of Part A was percentage change in Eczema Area Severity Index (“EASI”) score from baseline at Week 16. Secondary endpoints included EASI-75, EASI-90, Validated Investigator Global Assessment (“vIGA”) 0/1 and Itch Numeric Rating Scale (“Itch NRS”) at Week 16. In non-head-to-head trial comparisons, the initial 16-week findings from Part A included efficacy results, which compared favorably versus standard of care across endpoints, as well as rapid onset of itch relief and lesion reduction, and a favorable safety profile consistent with its class.

The Part A trial met its primary endpoint, with zumilokibart showing significantly greater least squares mean percent change from baseline at Week 16 with an EASI reduction of 71.0% compared to placebo of 33.8% (p 0.001). Zumilokibart showed the highest absolute and placebo-adjusted EASI-75 of any biologic in a 16-week global study with 66.9% of patients treated with zumilokibart achieving EASI-75 compared to 24.6% on placebo (p 0.001). Pre-specified sensitivity analysis showed consistent results in both moderate and severe patients based on baseline EASI score. The results demonstrated a vIGA 0/1 of 34.9% compared to placebo of 17.3% (p 0.05) and an EASI-90 of 33.9% compared to placebo of 14.7% (p 0.05). Treatment of patients with zumilokibart led to rapid and deep onset of itch relief and achieved a statistically significant reduction by Week 1, with a 50.7% reduction of Itch NRS from baseline compared to placebo of 23.2% (p 0.01) at Week 16. Zumilokibart was well-tolerated, with 56.1% of zumilokibart -exposed patients experiencing treatment-emergent adverse events (“TEAEs”) (vs. 63.4% in placebo). The most common TEAEs, occurring in more than 5% of patients, were non-infective conjunctivitis (14.6% vs. 2.4% in placebo), upper respiratory tract infection (8.5% vs 12.2% in placebo), nasopharyngitis (4.9% vs. 12.2% in placebo), and pain in extremity (0.0% vs. 7.3% in placebo) with the latter three being numerically lower in zumilokibart treated patients compared to placebo. Serious TEAEs were rare for zumilokibart -exposed patients (1.2% vs. 2.4% in placebo). The discontinuation rate due to adverse events was low for zumilokibart -exposed patients (2.4%). There were no injection site reactions in the zumilokibart treated group. In addition, improvement in asthma and sinusitis, as measured by improvements in the Asthma Control Questionnaire and Sinonasal Outcome Test in patients with comorbid asthma or sinusitis, was observed, which reflect zumilokibart’s potential to broadly impact Type 2 inflammatory disease.

All Part A patients that benefited from treatment in the induction arm received the opportunity to continue to zumilokibart maintenance treatment, which evaluated three and six-month dosing intervals. Patients in the placebo arm for the first 16 weeks also received the opportunity to receive an induction regimen of zumilokibart followed by three-month dosing of zumilokibart.

In March 2026, we announced positive 52‑week maintenance data from the Part A portion of the APEX Phase 2 clinical trial. The 52‑week maintenance portion of the trial evaluated 360mg of zumilokibart administered at three‑month and six‑month maintenance dosing intervals. Results focused on two analysis populations: the Week 16 zumilokibart responder population and the full 52-week zumilokibart-treated population. At Week 52, zumilokibart demonstrated strong maintenance of response among Week 16 responders, with deepening of efficacy across the full treated population for all lesion and itch endpoints. Among Week 16 responders, 75% and 85% of patients receiving three‑month and six‑month maintenance dosing, respectively, maintained EASI‑75. In addition, 86% and 78% of patients receiving three‑month and six‑month maintenance dosing, respectively, maintained a vIGA 0/1 at Week 52. Across the entire population treated with zumilokibart, responses improved through Week 52 for both every three - and six -month dosing regimens. vIGA 0/1 response of 72% and 52% was achieved at Week 52 for patients receiving three-month and six-month maintenance dosing, respectively, an improvement of 35% and 14% from Week 16 for the three-month and six-month dosing regimens, respectively. In addition, EASI-90 of 75% and 48% was achieved at Week 52 for patients receiving three-month and six-month maintenance dosing regimens, respectively, an improvement of 36% and 10% from Week 16 for the three-month and six-month regimens, respectively. EASI-100 of 41% and 19% was achieved at Week 52 for patients receiving three-month and six-month maintenance dosing regimens, respectively, an improvement of 33% and 11% from Week 16 for the three-month and six-month dosing regimens, respectively. Of patients who achieved EASI-90 at Week 16, 88% of patients with every 3-month dosing and 72% of patients with every 6-month dosing maintained such response at Week 52.

Zumilokibart was generally well tolerated over the 52‑week treatment period, with a safety profile consistent with other agents in its class. The most commonly reported TEAEs included non-infective conjunctivitis, upper respiratory tract infection, and nasopharyngitis.

In February 2025, we announced that we had commenced dosing of the Part B portion of the APEX Phase 2 trial. Part B is testing low, medium (Part A dose), and high dose regimens against placebo. In January 2026, we announced that we completed Part B enrollment ahead of schedule and exceeded target enrollment with a total of 347 patients. We expect to report 16-week topline induction data from Part B in the second quarter of 2026. Subject to positive results and regulatory alignment with the U.S. Food and Drug Administration (the “FDA”), we plan to initiate Phase 3 trials in AD in the second half of 2026, enabling a potential launch of zumilokibart for the treatment of AD in 2029.

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The APEX Part A induction regimen was designed to exceed EBGLYSS exposures by approximately 30% to 40% with potential for improved clinical outcomes and a maintenance regimen designed to equal lebrikizumab’s exposures. The results at Week 16 of the Part A study showed that patients in the highest zumilokibart exposure quartile (n=19) achieved the highest clinical response of any quartile in a post hoc exposure-response analysis. These patients had a mean 84.0% reduction in EASI from baseline, 89.5% of patients reaching EASI-75, 63.2% achieving IGA0/1, and 63.2% achieving EASI-90, demonstrating a robust response at the highest exposure level. The highest zumilokibart Part B dose was designed to exceed EBGLYSS exposures by approximately 90 to 100% which is similar to the exposure obtained in the highest quartile of the Part A results.

Phase 1b Trial in Patients with Asthma

In April 2025, we initiated a Phase 1b trial of zumilokibart (APG777) in patients with mild-to-moderate asthma, and in January 2026, we announced positive interim data from the trial. The trial is a double-bl

[Excerpt truncated for page length; source filing is linked above.]

Latest 10-K MD&A

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2026-03-02. 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 of our financial condition and results of operations in conjunction with the consolidated financial statements and related notes included elsewhere in this Annual Report on Form 10-K (this “Annual Report”). The following discussion contains forward-looking statements that reflect our current plans, forecasts, estimates and beliefs and involve risks and uncertainties. Our historical results are not necessarily indicative of the results that may be expected for any period in the future. Our actual results, outcomes and the timing of events could differ materially from those discussed in the forward-looking statements. Factors that could cause or contribute to these differences include those discussed below and elsewhere in this Annual Report, particularly in the section titled “Special Note Regarding Forward-Looking Statements” and “Risk Factors.” We urge you to consider these factors carefully in evaluating the forward-looking statements contained in this Annual Report. Forward-looking statements are not historical facts, reflect our current views with respect to future events, and apply only as of the date made. We do not intend, and undertake no obligation, to update these forward-looking statements, except as required by law. Unless the context requires otherwise, references to “we,” “us,” “our,” “Apogee” or “the Company” refer to Apogee Therapeutics, Inc. and its subsidiaries.

Overview

We are a clinical stage biotechnology company advancing optimized, novel biologics with the potential for differentiated efficacy and dosing in the largest inflammatory and immunology (“I&I”) markets, including for the treatment of atopic dermatitis (“AD”), asthma, eosinophilic esophagitis (“EoE”), chronic obstructive pulmonary disease (“COPD”), and other I&I indications. Our antibody programs are designed to overcome limitations of existing therapies by targeting well-established mechanisms of action and incorporating advanced antibody engineering to optimize half-life and other properties.

Our pipeline comprises multiple antibody programs being developed initially for the treatment of I&I indications as monotherapies and combinations, including zumilokibart (APG777), APG279 (zumilokibart + APG990), APG273 (zumilokibart + APG333), and APG808 (each, a “program” or “product candidate”). With four validated targets in our portfolio, we are seeking to achieve best-in-class efficacy and dosing through monotherapies and combinations of our novel antibodies. Based on a broad pipeline and depth of expertise, we believe we can deliver value and meaningful benefit to patients underserved by today’s standard of care. We believe each of our product candidates has potential for broad application across multiple I&I indications.

Recent Developments

The following is a summary of key developments affecting our business for the year ended December 31, 2025, except for updates related to our programs, which are discussed in “Item 1. Business” included in this Annual Report.

Equity Offerings

On October 10, 2025, pursuant to our Registration Statement on Form S-3, which became effective in August 2024 (File No 333-281503), we issued and sold an aggregate of 8,048,782 shares of common stock (inclusive of 1,097,561 shares of common stock pursuant to the exercise in full of the underwriters’ option to purchase additional shares) at a public offering price of $41.00 per share, and, in lieu of common stock to certain investors, pre-funded warrants to purchase up to 365,853 shares of common stock at a public offering price of $40.99999 per pre-funded warrant (the “October 2025 Offering”). The pre-funded warrants have an exercise price of $0.00001 per share and are exercisable immediately. The aggregate net proceeds from the offering were $324.1 million after deducting underwriting discounts and commissions, and estimated offering expenses payable by us.

ATM Facility

During the year ended December 31, 2025, we sold 1,175,701 shares of common stock under our at the market offering program (“ATM Facility”) for gross proceeds of $67.6 million, less commissions and other offering expenses of $2.0 million.

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Net Loss

We have incurred significant operating losses since inception. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of any programs we may develop. We generated a net loss of $255.8 million for the year ended December 31, 2025. As of December 31, 2025, we had an accumulated deficit of $561.8 million. We expect to continue to incur significantly increased expenses for the foreseeable future if and as we continue to operate our business.

Macroeconomic Conditions

The global macroeconomic environment is uncertain, and could be negatively affected by, among other things, financial market volatility and uncertainty, inflation, interest rate fluctuations, changing tariff policies and trade restrictions, uncertainty with respect to the federal budget and debt ceiling and potential government shutdowns related thereto, instability in the global banking system, cybersecurity events, the impact of war or military conflict, including regional conflicts around the world, and public health pandemics. We closely monitor the impact of these factors on all aspects of our business, including the potential impacts on our clinical trial trials, supply chain, regulatory interactions, employees, third-party partners, suppliers, and vendors. The ultimate impact of global and domestic economic conditions on our business remains highly uncertain and will depend on future developments and factors that continue to evolve. As a result, we are subject to continuing risks and uncertainties and continue to closely monitor the impact of the current conditions on our business. For more information regarding these risks and uncertainties, see the section titled “Risk Factors” in this Annual Report.

Overview of Financial Results

Revenue

We have not generated any revenue from product sales and do not expect to generate any revenue from the sale of products for several years, if at all. If our development efforts for our programs are successful and result in regulatory approval or 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.

Operating Expenses

Our operating expenses consist of (i) research and development expenses and (ii) general and administrative expenses.

Research and Development

Research and development expenses consist primarily of costs incurred in connection with the development and research of our programs. These expenses include:

•
the cost of developing and validating our manufacturing process for use in our preclinical studies and current and future clinical trials;

•
expenses incurred in connection with continuing our current research programs and preclinical development of any programs we may identify, including under agreements with third parties, such as consultants and contractors;

•
costs of funding research performed by third parties, including Paragon, that conduct research and development and preclinical or clinical activities on our behalf;

•
the cost to acquire in-process research and development, with no alternative future use associated with asset acquisitions, such as the Option Agreements, and License Agreements;

•
expenses incurred under agreements with clinical trial sites and clinical research organizations (“CROs”) that conduct research and development activities on our behalf, including clinical trial execution, project management, data management and related outsourced services;

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•
costs related to production of clinical supplies and preclinical materials, including fees paid to contract manufacturers; and

•
personnel-related expenses, including salaries, bonuses and equity-based compensation expense.

We measure and recognize asset acquisitions or licenses to intellectual property that are not deemed to be business combinations based on the cost to acquire or license the asset or group of assets, which includes transaction costs. In an asset acquisition or license to intellectual property, the cost allocated to acquired in-process research and development, with no alternative future use is recognized as research and development expense on the acquisition date.

We expense research and development costs as incurred. Non-refundable advance payments that we make for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are delivered or the services are performed, or when it is no longer expected that the goods will be delivered or the services rendered.

Our primary focus since inception has been the identification and development of our pipeline programs. Our research and development costs primarily consist of external costs, including CRO fees and fees paid to Paragon under the Option Agreements and the License Agreements. We do not separately track or segregate the amount of costs incurred under the Option Agreements due to the early-stage and discovery nature of the services. We do not allocate personnel-related costs by program because these resources are used and these costs are deployed across multiple programs under development, and, as such, are not separately classified.

We expect that our research and development expenses will increase substantially for the foreseeable future as we continue to invest in research and development activities for our programs, and any potential future programs, including investments in clinical trials and manufacturing. The success of programs we may identify and develop will depend on many factors, including the following:

•
timely and successful completion of preclinical studies;

•
effective Investigational New Drug applications (“INDs”) or comparable foreign applications that allow commencement of our planned clinical trials or future clinical trials for any programs we may develop;

•
successful enrollment and completion of clinical trials;

•
positive results from our future clinical trials that support a finding of safety and effectiveness, acceptable PK profile, and an acceptable risk-benefit profile in the intended populations;

•
receipt of marketing approvals from applicable regulatory authorities;

•
establishment of arrangements through our own facilities or with third-party manufacturers for clinical supply and, where applicable, commercial manufacturing capabilities;

•
establishment, maintenance, defense and enforcement of patent, trademark, trade secret and other intellectual property protection or regulatory exclusivity for any products we may develop; and

•
maintenance of a continued acceptable safety, tolerability and efficacy profile of any programs we may develop following approval.

Any changes in the outcome of any of these variables with respect to the development of programs that we may identify could mean a significant change in the costs and timing associated with the development of such programs. For example, if the U.S. Food and Drug Administration (“FDA”) or another regulatory authority were to require us to conduct clinical trials beyond those that we currently anticipate will be required for the completion of clinical development of a program, or if we experience significant delays in our clinical trials due to patient enrollment, macroeconomic events or other reasons, we would be required to expend significant additional financial resources and time on the completion of clinical development. We may never obtain regulatory approval for any of our programs.

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General and Administrative

General and administrative expenses consist primarily of personnel-related expenses, including salaries, bonuses, and equity-based compensation, for individuals in our executive, finance, legal, IT, operations, human resources, business development, commercial and other administrative functions. Other significant general and administrative expenses include legal fees relating to corporate matters, professional fees for accounting, auditing, tax and administrative consulting services, insurance costs and recruiting costs. These costs relate to the operation of the business, unrelated to the research and development function, or any individual program.

We expect that our general and administrative expenses will increase substantially for the foreseeable future as we increase our headcount to support the expected growth in our research and development activities and the potential commercialization of our product candidates, if approved. We also expect to continue incurring expenses associated with being a public company, including increased costs of accounting, audit, legal, regulatory and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer insurance costs, and investor and public relations costs.

Other Income (Expense), Net

Interest Income

Interest income consists of interest income earned from our cash, cash equivalents, and marketable securities and amortization of investment discounts.

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 generated in each period as we believe, based upon the weight of available evidence, that it is more likely than not that all of our net operating loss (“NOL”) carryforwards and the vast majority of our tax credit carryforwards will not be realized.

As of December 31, 2025, we had U.S. federal NOL carryforwards of approximately $250.7 million, which may be available to reduce future taxable income and have an indefinite carryforward period but are limited in their usage to an annual deduction equal to 80% of annual taxable income. We also had state net operating loss carryforwards of approximately $94.3 million, which will begin to expire in 2043 for state tax purposes. As of December 31, 2025, we also had U.S. federal and research and development tax credit carryforwards of approximately $16.7 million, which may be available to reduce future tax liabilities. We also had California research and development credit carryforwards of approximately $2.9 million. Additionally, we had Massachusetts research and development credit carryforwards of approximately $1.7 million. The U.S. federal and Massachusetts research and development tax credit carryforwards expire at various dates beginning in 2042 and the California research and development tax credit carryforwards do not expire. We have recorded a full valuation allowance against our net deferred tax assets at the balance sheet date.

Results of Operations

A discussion regarding our financial condition and results of operations for the year ended December 31, 2025 compared to the year ended December 31, 2024 is presented below. A discussion regarding our financial condition and results of operations for the year ended December 31, 2024 compared to the year ended December 31, 2023 can be found in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on March 3, 2025.

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Comparison of the Year Ended December 31, 2025 and Year Ended December 31, 2024

The following table summarizes our consolidated statements of operations for the periods presented (in thousands):

YEAR ENDED DECEMBER 31,

2025

2024

$ CHANGE

Operating expenses:

Research and development

$

214,712

$

167,865

$

46,847

General and administrative

70,883

49,005

21,878

Total operating expenses

285,595

216,870

68,725

Loss from operations

(285,595

)

(216,870

)

(68,725

)

Other income, net:

Interest income

30,030

34,742

(4,712

)

Total other income, net

30,030

34,742

(4,712

)

Net loss before taxes

(255,565

)

(182,128

)

(73,437

)

Provision for income taxes

(278

)

(18

)

(260

)

Net loss after taxes

$

(255,843

)

$

(182,146

)

$

(73,697

)

Research and Development Expense

The following table summarizes our research and development expenses incurred for the periods presented (in thousands):

YEAR ENDED DECEMBER 31,

2025

2024

External research and development costs by program:

Zumilokibart (APG777)

$

76,441

$

49,241

APG990/APG279

16,250

20,000

APG333/APG273

5,257

28,095

APG808

3,136

10,311

Unallocated research and development costs:

External-discovery related costs and other

22,469

11,064

Personnel-related (excluding equity-based compensation)

68,490

39,013

Equity-based compensation

22,381

9,964

Depreciation expense

288

177

Total research and development expenses

$

214,712

$

167,865

Research and development expenses for the years ended December 31, 2025 and 2024 were $214.7 million and $167.9 million, respectively. The increase of $46.8 million was primarily driven by further development of our zumilokibart (APG777) program, increases in personnel costs and equity-based compensation, associated with the growth in our research and development team, and increases in external-discovery related costs and other expenses, partially offset by decreases in expenses related to our APG990/APG279, APG333/APG273 and APG808 programs.

Research and development expense related to the zumilokibart (APG777) program increased by $27.2 million in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily driven by increases in clinical trial-related expenses and clinical manufacturing activities to support our ongoing clinical trials. Research and development expense related to the APG990/APG279 program decreased by $3.8 million in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily due to a reduction in clinical manufacturing activities and a decrease in expenses incurred under the Option Agreements and License Agreements, which included milestone payments of $1.0 million and $2.0 million to Paragon, related to the nomination of a development candidate in May 2024 and the first dosing of human participants in a Phase 1 clinical trial in August 2024, respectively, partially offset by an increase in clinical trial expenses. Research and development expense related to the APG333/APG273 program decreased by $22.8 million in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily due to a reduction in clinical manufacturing activities and a decrease in

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expenses incurred under the Option Agreements and License Agreements, which included a $2.0 million research initiation fee and milestone payments of $3.0 million and $5.0 million to Paragon related to the nomination of a development candidate in October 2024 and the first dosing of a human patient in a Phase 1 clinical trial in December 2024, respectively. Research and development expense related to the APG808 program decreased by $7.2 million in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily driven by decreases in clinical trial expenses, expenses incurred under the Option Agreements and License Agreements, including a milestone payment of $2.0 million to Paragon in March 2024 for the first dosing of a human patient in a Phase 1 trial, and a decrease in clinical manufacturing expenses.

External-discovery related costs and other expenses increased by $11.4 million in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily due to increases in professional service fees and non-program specific research and development expense. Personnel-related expenses and equity-based compensation increased by $29.5 million and $12.4 million, respectively, in the year ended December 31, 2025, compared to the year ended December 31, 2024, primarily due to increased headcount and an increase in the fair value of equity awards granted.

General and Administrative Expense

The following table summarizes our general and administrative expenses for the periods presented (in thousands):

YEAR ENDED DECEMBER 31,

2025

2024

Personnel-related (excluding equity-based compensation)

$

26,740

$

16,935

Equity-based compensation

23,896

13,368

Legal and professional fees

4,315

6,451

Depreciation expense

1,130

—

Other

14,802

12,251

Total general and administrative expenses

$

70,883

$

49,005

General and administrative expenses for the year ended December 31, 2025 were $70.9 million, compared to $49.0 million for the year ended December 31, 2024. The increase of $21.9 million was primarily due to increases of $9.8 million and $10.5 million in personnel-related expense and equity-based compensation, respectively, primarily driven by increased headcount and an increase in the fair value of equity awards granted.

Other Income, Net

Interest income decreased $4.7 million for the year ended December 31, 2025, compared to the year ended December 31, 2024, which was primarily related to interest on our cash, cash equivalents and marketable securities.

Liquidity and Capital Resources

Sources of Liquidity

Since our inception, we have incurred significant losses. We have not yet commercialized any of our programs, which are in various phases of early-stage and late-stage development, and we do not expect to generate revenue from sales of any of our programs for several years, if at all. To date, we have financed our operations from the proceeds from the issuance of preferred units and the sale of common stock in our IPO, our March 2024 Offering (as defined below), our ATM Facility and our October 2025 Offering. As of December 31, 2025, we had cash and cash equivalents of $131.5 million, marketable securities of $598.6 million and long-term marketable securities of $172.7 million.

Prior to our IPO, we received gross proceeds of $169.0 million from the sales of our preferred units. In connection with our IPO in July 2023, we issued and sold an aggregate of 20,297,500 shares of common stock (inclusive of 2,647,500 shares of common stock pursuant to the exercise in full of the underwriters’ option to purchase

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additional shares) at a price of $17.00 per share for net proceeds of $315.4 million, after deducting underwriting discounts and commissions, and other offering expenses.

In March 2024, we issued and sold an aggregate of 7,790,321 shares of common stock (inclusive of 1,016,128 shares pursuant to the exercise in full of the underwriters’ option to purchase additional shares) at a public offering price of $62.00 per share, for net proceeds of $450.0 million after deducting underwriting discounts and commissions, and other offering expenses (the “March 2024 Offering”).

In August 2024, we entered into an Open Market Sale Agreement (the “Sale Agreement”) with Jefferies LLC (the “Sales Agent”), pursuant to which we may offer and sell shares of common stock up to a maximum aggregate offering price of $300.0 million, from time to time, through an ATM Facility. During the year ended December 31, 2024, we sold 926,049 shares of common stock under the ATM Facility for gross proceeds of $44.9 million, less commissions and other offering expenses of $1.4 million. During the year ended December 31, 2025 we sold 1,175,701 shares of common stock under the ATM Facility for gross proceeds of $67.6 million, less commissions and other offering expenses of $2.0 million. As of December 31, 2025, $187.5 million remained available for sale under the Sale Agreement.

In connection with our October 2025 Offering, we issued and sold an aggregate of 8,048,782 shares of common stock (inclusive of 1,097,561 shares of common stock pursuant to the exercise in full of the underwriters’ option to purchase additional shares) at a public offering price of $41.00 per share, and, in lieu of common stock to certain investors, pre-funded warrants to purchase up to 365,853 shares of common stock at a public offering price of $40.99999 per pre-funded warrant. The pre-funded warrants have an exercise price of $0.00001 per share and are exercisable immediately. The aggregate net proceeds from the offering were $324.1 million after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

Future Funding Requirements

To date, we have not generated any revenue from product sales. We do not expect to generate revenue from product sales unless and until we successfully complete preclinical and clinical development of, receive regulatory approval for, and commercialize a product candidate and we do not know when that will occur, if at all. We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we advance the preclinical and clinical activities. In addition, if we obtain regulatory approval for any product candidates, we expect to incur significant expenses related to product sales, marketing, and distribution to the extent that such sales, marketing and distribution are not the responsibility of potential collaborators. We expect to incur additional costs associated with operating as a public company. The timing and amount of our operating expenditures will depend largely on the factors set out above. For more information, see the section titled “Risk Factors—Risks Related to Our Limited Operating History, Financial Position and Capital Requirements.”

Our funding requirements and timing and amount of our operating expenditures will depend on many factors, including, but not limited to:

•
the rate of progress in the development of our zumilokibart (APG777), APG279, APG273, and APG808 programs;

•
the scope, results and costs of preclinical studies and clinical trials for any other current and future programs;

•
the number and characteristics of programs and technologies that we develop or may in-license;

•
the costs and timing of potential future commercialization activities, including manufacturing, marketing, sales and distribution, for any of our product candidates for which we receive marketing approval;

•
the costs necessary to obtain regulatory approvals, if any, for any approved products in the United States and other jurisdictions, and the costs of post-marketing studies that could be required by regulatory authorities in jurisdictions where approval is obtained;

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•
the costs and timing of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights and defending any intellectual property-related claims, including claims of infringement, misappropriation or other violation of third-party intellectual property;

•
the continuation of our existing licensing arrangements and entry into new collaborations and licensing arrangements;

•
the costs we incur in maintaining business operations;

•
the costs of hiring additional clinical, quality control, manufacturing and other scientific personnel;

•
the costs of adding operational, financial and management information systems and personnel;

•
adverse global macroeconomic conditions, including inflation, slower growth or recession, new or increased tariffs and other barriers to trade, changes to fiscal and monetary policy or government budget dynamics (particularly in the pharmaceutical and biotech areas), government shutdowns, volatility in financial markets and other challenges in the global economy;

•
the costs associated with being a public company;

•
the costs and timing of future laboratory facilities;

•
the revenue, if any, received from commercial sales of our product candidates for which we receive marketing approval;

•
the effect of competing technological and market developments; and

•
the extent to which we acquire or invest in businesses, products and technologies, including entering into licensing or collaboration arrangements for programs.

•
Identifying potential programs and product candidates and conducting preclinical studies and clinical trials is a time consuming, expensive and uncertain process that takes years to complete, and we may never generate the necessary data or results required to obtain marketing approval and achieve product sales. In addition, our product candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of products that we do not expect to be commercially available for many years, if ever. Accordingly, we will need to obtain substantial additional funds to achieve our business objectives.

Adequate additional funds may not be available to us on acceptable terms, or at all. We do not currently have any committed external source of funds. To the extent that we raise additional capital through the sale of equity or convertible debt securities, our stockholders’ ownership interests could be diluted, and the terms of these securities may include liquidation or other preferences that could adversely affect our stockholders’ rights.

Additional debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring debt, making capital expenditures or declaring dividends, and may require the issuance of warrants, which could potentially dilute our stockholders’ ownership interests.

If we raise additional funds through strategic collaborations, licensing arrangements, royalty financings or other collaborations with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs, or product candidates or grant licenses on terms that may not be favorable to us. Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our business.

If we are unable to raise additional funds when needed or on acceptable terms, we may be required to delay, limit, suspend, or terminate our product development programs or any future commercialization efforts or grant rights to develop and market product candidates to third parties that we would otherwise prefer to develop and market ourselves.

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As of December 31, 2025, we had $131.5 million of cash and cash equivalents, $598.6 million of marketable securities and $172.7 million of long-term marketable securities. Based on our current operating plan, as of the date of this Annual Report, we estimate that our existing cash, cash equivalents, marketable securities and long-term marketable securities will be sufficient to enable us to fund our operating expenses and capital expenditure requirements through at least the next 12 months following the issuance of our consolidated financial statements included elsewhere in this Annual Report. Moreover, based on our current operating plan, we estimate that such funds will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the second half of 2028. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect.

Cash Flows

The following table provides information regarding our cash flows for the periods presented (in thousands):

YEAR ENDED DECEMBER 31,

2025

2024

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

Operating activities

$

(227,450

)

$

(171,174

)

Investing activities

(179,574

)

(300,462

)

Financing activities

396,490

495,109

Net (decrease) increase in cash, cash equivalents, and restricted cash

$

(10,534

)

$

23,473

Net Cash used in Operating Activities

Net cash used in operating activities resulted primarily from our net losses adjusted for non-cash charges and changes in components of operating assets and liabilities, which are generally attributable to timing of payments, and the related effect on certain account balances, operational and strategic decisions and contracts to which we may be a party.

For the year ended December 31, 2025, operating activities used $227.5 million of cash, primarily due to a net loss of $255.8 million, net changes in our operating assets and liabilities of $15.5 million and amortization of discounts on marketable securities of $7.5 million. This was partially offset by non-cash charges of $46.3 million for equity-based compensation and $3.7 million related to lease expense.

For the year ended December 31, 2024, operating activities used $171.2 million of cash, primarily due to a net loss of $182.1 million and amortization of discounts on marketable securities of $12.2 million. This was partially offset by non-cash charges of $23.3 million for equity-based compensation and $1.7 million related to lease expense.

Net Cash used in Investing Activities

Net cash used in investing activities for the year ended December 31, 2025 was $179.6 million, primarily related to the $642.3 million purchase of marketable securities and $5.1 million purchase of property and equipment. This was partially offset by the maturities of $467.9 million of marketable securities.

Net cash used in investing activities for the year ended December 31, 2024 was $300.5 million, primarily related to the $649.5 million purchase of marketable securities and $1.1 million purchase of property and equipment. This was partially offset by the maturities of $350.1 million of marketable securities.

Net Cash provided by Financing Activities

For the year ended December 31, 2025, financing activities provided $396.5 million of cash, primarily related to the issuance and sale of common stock from our October 2025 Offering, net of paid issuance costs, and the issuance of common stock under our ATM Facility.

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For the year ended December 31, 2024, financing activities provided $495.1 million of cash, primarily related to the issuance and sale of common stock from our March 2024 Offering, net of paid issuance costs, and the issuance of common stock under our ATM Facility in December 2024.

Contractual Obligations and Other Commitments

We enter into contracts in the normal course of business with CROs, CMOs and other third parties for preclinical research studies and testing, clinical trials, manufacturing and other services. Payments due upon cancellation consist only of payments for services provided and expenses incurred up to the date of cancellation, including non-cancelable obligations of our service providers and, in some cases, wind-down costs. The exact amounts of such obligations are dependent on the timing of termination and the terms of the associated agreement. Accordingly, these payments are not disclosed as the amount and timing of such payments are not known.

Our agreements to license intellectual property include potential milestone payments that are dependent upon the development of products using the intellectual property licensed under the agreements and contingent upon the achievement of specific development and clinical milestones. As of December 31, 2025, we have incurred $17.0 million of the maximum aggregate potential milestone payments. We are also obligated to pay royalties to (i) Paragon at a royalty rate of a low single-digit percentage based on net sales of any products under the License Agreements, once commercialized and (ii) WuXi Biologics at a royalty rate of a fraction of a single digit percentage of global net sales of WuXi Biologics Licensed Products manufactured by a third-party manufacturer.

We do not have any off-balance sheet arrangements that are material or reasonably likely to become material to our financial condition or results of operations.

Critical Accounting Policies and Significant Judgments and Estimates

Our management’s discussion and analysis of our financial condition and results of operations is based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States. The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, as well as the reported revenues recognized and expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

We define our critical accounting policies as those accounting principles generally accepted in the United States of America that are most critical to the judgments and estimates used in the preparation of our consolidated financial statements. While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements appearing elsewhere in this Annual Report, we believe the following accounting policies used in preparation of our consolidated financial statements require the most significant judgments and estimates.

Research and Development Expense

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, overhead costs, contract services and other related costs. The value of goods and services received from CROs and CMOs in the reporting period are estimated based on the level of services performed, and progress in the period in cases when we have not received an invoice from the supplier. In circumstances where amounts have been paid in excess of costs incurred, we record a prepaid expense. When billing terms under these contracts do not coincide with the timing of when the work is performed, we are required to make estimates of outstanding obligations to those third parties as of period end. Any accrual estimates are based on a number of factors, including our knowledge of the progress towards completion of the specific tasks to be performed, invoicing to date under the contracts, communication from the vendors of any actual costs incurred during the period that have not yet been invoiced and the costs included in the contracts.

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Significant judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made by us.

Recently Issued Accounting Pronouncements

We have reviewed all recently issued accounting standards and have determined that, other than as disclosed in Note 2 to our consolidated financial statements included elsewhere in this Annual Report, such standards are not expected to have a material impact on our consolidated financial statements or do not otherwise apply to our operations.