0001104659-26-095448 | 10-Q | XBRL Viewer

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License and Collaboration Revenue (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended			6 Months Ended
	Jan. 31, 2025	Oct. 31, 2024	Aug. 31, 2023	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
License and Collaboration Revenue
Revenue				$ 1,000			$ 1,000	$ 10,000
BMS Agreement
License and Collaboration Revenue
Amount of upfront cash payment received			$ 50,000
Maximum amount of payments receivable			79,500
Sales milestone payments receivable			$ 70,000
Amount receivable				800	$ 1,300		800	1,300
Reduction in research and development costs pertaining to reimbursed global development costs				800	1,300		1,900	3,000
Revenue				0	0		0	0
Tenacia Novation Agreement
License and Collaboration Revenue
Amount of upfront cash payment received		$ 5,000
Maximum amount of payments receivable		$ 85,000
Revenue				$ 1,000	$ 0		$ 1,000	$ 0
License Agreement with Zai Lab (Hong Kong) Limited
License and Collaboration Revenue
Amount of upfront cash payment received	$ 10,000
Maximum amount of payments receivable	117,000
Agreement transaction price						$ 10,000
Viridian Agreement
License and Collaboration Revenue
Development milestone expense payable	$ 21,000

Fair Value Measurements

6 Months Ended

Jun. 30, 2026

Fair Value Measurements

Fair Value Measurements

3.Fair Value Measurements

The following table presents information about the Company’s financial assets that are regularly measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value (in thousands):


			As of June 30, 2026
Description			Total Carrying Value		Quoted Prices in Active Market (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Observable Inputs (Level 3)
Assets:
Cash		$	115,202	$	115,202	$	—	$	—
Money market funds			81,375		81,375		—		—
Short-term investments:
Commercial paper			24,217		—		24,217		—
Corporate debt securities			78,902		—		78,902		—
Government securities			343,430		343,430		—		—
Long-term investments:
Corporate debt securities			16,648		—		16,648		—
Government securities			14,115		14,115		—		—
Total assets		$	673,889	$	554,122	$	119,767	$	—


			As of December 31, 2025
Description			Total Carrying Value		Quoted Prices in Active Market (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Observable Inputs (Level 3)
Assets:
Cash		$	13,038	$	13,038	$	—	$	—
Money market funds			97,603		97,603		—		—
Short-term investments:
Commercial paper			5,959		—		5,959		—
Corporate debt securities			44,299		—		44,299		—
Government securities			182,293		182,293		—		—
Long-term investments:
Corporate debt securities			1,467		—		1,467		—
Government securities			15,805		15,805		—		—
Total assets		$	360,464	$	308,739	$	51,725	$	—

For information on the fair value of the Company’s long-term liabilities, see Note 6, Long-Term Obligations and Note 9, Royalty Obligation, to these unaudited condensed consolidated financial statements.

There have been no material impairments of the Company’s assets measured and carried at fair value as of June 30, 2026 and December 31, 2025. In addition, there have been no changes in valuation techniques as of June 30, 2026 and December 31, 2025. The fair value of Level 1 instruments classified as money market funds and government securities are valued using quoted market prices in active markets. The fair value of Level 2 instruments classified as short-term investments was determined using other than quoted prices in active markets, which are either directly or indirectly observable as of the reporting date and fair value is determined using models or other valuation methodologies. During the six months ended June 30, 2026 and year ended December 31, 2025, there were no transfers between levels.

The short and long-term investments are classified as available-for-sale securities. As of June 30, 2026, the remaining contractual maturities of the available-for-sale securities were 1 to 16 months, and the balance in the Company’s accumulated other comprehensive income was comprised of activity related to the Company’s available-for-sale securities. There were no realized gains or losses recognized on the sale or maturity of available-for-sale securities during the three and six months ended June 30, 2026 and 2025. As a result, the Company did not reclassify any amounts out of accumulated other comprehensive income for the same period. The Company had a limited number of available-for-sale securities in insignificant loss positions as of June 30, 2026, which the Company does not intend to sell and has concluded it will not be required to sell before recovery of amortized cost for the investment maturity.

The following table summarizes the available-for-sale securities (in thousands):


	As of June 30, 2026
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Commercial paper	$	24,236	$	—	$	(19)	$	24,217
Corporate debt securities		95,670		2		(122)		95,550
Government securities		358,340		1		(796)		357,545
Total	$	478,246	$	3	$	(937)	$	477,312


	As of December 31, 2025
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Commercial paper	$	5,957	$	2	$	—	$	5,959
Corporate debt securities		45,740		28		(2)		45,766
Government securities		197,939		162		(3)		198,098
Total	$	249,636	$	192	$	(5)	$	249,823

Certain short-term debt securities with original maturities of less than 90 days are included in cash and cash equivalents on the condensed consolidated balance sheets and are not included in the table above.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

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+ Details

Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2026
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2.Summary of Significant Accounting Policies The Company’s significant accounting policies are disclosed in Note 2, Summary of Significant Accounting Policies, in the audited consolidated financial statements for the year ended December 31, 2025, and notes thereto, included in the Company’s Annual Report on Form 10-K that was filed with the SEC on March 16, 2026. Since the date of those financial statements, other than disclosed herein, there have been no material changes to the Company’s significant accounting policies. Basis of Presentation and Consolidation The accompanying condensed consolidated financial statements include the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts, transactions, and balances have been eliminated in consolidation. The accompanying condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). Unaudited Interim Financial Information The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited financial statements and in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2026, and the results of operations and its cash flows for the three and six months ended June 30, 2026 and 2025. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2026 and 2025 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, any other interim periods, or any future year or period. These interim financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2025, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K as filed with the SEC, on March 16, 2026. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses, and related disclosures. The Company bases its estimates on historical experience, known trends and other market-specific factors or other relevant factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis using such factors and adjusts those estimates and assumptions as facts and circumstances dictate. Actual results may differ from those estimates or assumptions. Significant estimates in these unaudited condensed consolidated financial statements include estimates made in connection with accrued research and development expenses, stock-based compensation, valuations of embedded features within its senior secured term loan and the liability related to the sale of future royalties including the estimation of future payments and the related non-cash interest expense. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgement. As of the date of the issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgements or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s financial statements. Embedded Derivative Financial Instruments The Company evaluates its financial instruments, including its convertible senior notes and senior secured term loan to determine if such instruments are derivatives or contain features that qualify as embedded derivatives in accordance with ASC 815 “Derivatives and Hedging.” ASC 815 generally provides three criteria that, if met, require companies to bifurcate embedded features from their host instruments and account for them as free-standing derivative financial instruments. The three criteria include circumstances in which (a) the economic characteristics and risks of the embedded derivative instrument are not clearly and closely related to the economic characteristics and risks of the host contract, (b) the hybrid instrument that embodies both the embedded derivative instrument and the host contract is not remeasured at fair value under otherwise applicable generally accepted accounting principles with changes in fair value reported in earnings as they occur, and (c) a separate instrument with the same terms as the embedded derivative would be considered a derivative instrument. If liability accounting is required, the Company’s derivative instruments are recorded at fair value with an offsetting amount recorded as a debt discount, which offsets the carrying amount of the debt. The derivative is revalued at the end of each reporting period and any change in fair value is recorded as a gain or loss in the statement of operations. The debt discount is amortized through interest expense over the life of the debt using the straight-line method. Convertible Instruments When the Company issues debt with a conversion feature, in accordance with ASC 815, “Derivatives and Hedging” it must first assess whether the conversion feature meets the requirements to be treated as a derivative. An embedded equity-linked component that meets the definition of a derivative does not have to be separated from the host instrument if the component qualifies for the scope exception for certain contracts involving an issuer’s own equity. The scope exception applies if the contract is both (a) indexed to its own stock; and (b) classified in stockholders’ equity in its balance sheet. Debt and Debt Issuance Costs Debt issuance costs and expenses paid by the Company to its lenders are presented on the unaudited condensed consolidated balance sheet as a direct deduction from the related liability. Debt issuance costs represent costs that are paid directly to third parties and directly attributable to the issuance of a debt or equity instrument, which includes lender fees, legal expenses and other direct costs. These costs are amortized as a non-cash component of interest expense using the effective interest method over the term of the debt. Costs and discounts are presented as a reduction of the related debt in the accompanying balance sheet if related to the issuance of debt or presented as a reduction of additional paid in capital if related to the issuance of an equity instrument. Recently Adopted Accounting Standards In September of 2025, the FASB issued ASU 2025-07: Derivates and Hedging (ASC 815) and Revenue from Contracts with Customers (ASC 606). This ASU expands the scope exceptions in the derivative guidance to exclude certain non-exchange-trade contracts with underlyings based on the operations or activities of one of the parties to the contract, including the occurrence or nonoccurrence of an event specific to those operations or activities. The ASU also clarifies that share-based noncash consideration received from a customer in exchange for goods or services should be accounted for as noncash consideration under ASC 606 unless and until the entity’s rights to receive or retain such consideration becomes unconditional. The Company early adopted the ASU at the beginning of fiscal year 2026, using the prospective method. The adoption of this new accounting standard was applied to the evaluation of the senior secured term loan that was executed during the first quarter. Recent Accounting Pronouncements In November 2024, the FASB issued 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires entities to disclose additional information about specific expense categories in the notes to the financial statements. ASU 2024-03 is effective for annual periods beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively to the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its unaudited condensed consolidated financial statements and related disclosures. From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that the Company adopts as of the specified effective date. Unless otherwise discussed, the Company does not believe that the adoption of recently issued standards have or may have a material impact on its unaudited condensed consolidated financial statements or disclosures.

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2026

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

2.Summary of Significant Accounting Policies

The Company’s significant accounting policies are disclosed in Note 2, Summary of Significant Accounting Policies, in the audited consolidated financial statements for the year ended December 31, 2025, and notes thereto, included in the Company’s Annual Report on Form 10-K that was filed with the SEC on March 16, 2026. Since the date of those financial statements, other than disclosed herein, there have been no material changes to the Company’s significant accounting policies.

Basis of Presentation and Consolidation

The accompanying condensed consolidated financial statements include the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts, transactions, and balances have been eliminated in consolidation. The accompanying condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Unaudited Interim Financial Information

The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited financial statements and in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2026, and the results of operations and its cash flows for the three and six months ended June 30, 2026 and 2025. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2026 and 2025 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, any other interim periods, or any future year or period. These interim financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2025, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K as filed with the SEC, on March 16, 2026.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses, and related disclosures. The Company bases its estimates on historical experience, known trends and other market-specific factors or other relevant factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis using such factors and adjusts those estimates and assumptions as facts and circumstances dictate. Actual results may differ from those estimates or assumptions. Significant estimates in these unaudited condensed consolidated financial statements include estimates made in connection with accrued research and development expenses, stock-based compensation, valuations of embedded features within its senior secured term loan and the liability related to the sale of future royalties including the estimation of future payments and the related non-cash interest expense.

Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgement. As of the date of the issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgements or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s financial statements.

Embedded Derivative Financial Instruments

The Company evaluates its financial instruments, including its convertible senior notes and senior secured term loan to determine if such instruments are derivatives or contain features that qualify as embedded derivatives in accordance with ASC 815 “Derivatives and Hedging.” ASC 815 generally provides three criteria that, if met, require companies to bifurcate embedded features from their host instruments and account for them as free-standing derivative financial instruments. The three criteria include circumstances in which (a) the economic characteristics and risks of the embedded derivative instrument are not clearly and closely related to the economic characteristics and risks of the host contract, (b) the hybrid instrument that embodies both the embedded derivative instrument and the host contract is not remeasured at fair value under otherwise applicable generally accepted accounting principles with changes in fair value reported in earnings as they occur, and (c) a separate instrument with the same terms as the embedded derivative would be considered a derivative instrument.

If liability accounting is required, the Company’s derivative instruments are recorded at fair value with an offsetting amount recorded as a debt discount, which offsets the carrying amount of the debt. The derivative is revalued at the end of each reporting period and any change in fair value is recorded as a gain or loss in the statement of operations. The debt discount is amortized through interest expense over the life of the debt using the straight-line method.

Convertible Instruments

When the Company issues debt with a conversion feature, in accordance with ASC 815, “Derivatives and Hedging” it must first assess whether the conversion feature meets the requirements to be treated as a derivative. An embedded equity-linked component that meets the definition of a derivative does not have to be separated from the host instrument if the component qualifies for the scope exception for certain contracts involving an issuer’s own equity. The scope exception applies if the contract is both (a) indexed to its own stock; and (b) classified in stockholders’ equity in its balance sheet.

Debt and Debt Issuance Costs

Debt issuance costs and expenses paid by the Company to its lenders are presented on the unaudited condensed consolidated balance sheet as a direct deduction from the related liability. Debt issuance costs represent costs that are paid directly to third parties and directly attributable to the issuance of a debt or equity instrument, which includes lender fees, legal expenses and other direct costs. These costs are amortized as a non-cash component of interest expense using the effective interest method over the term of the debt. Costs and discounts are presented as a reduction of the related debt in the accompanying balance sheet if related to the issuance of debt or presented as a reduction of additional paid in capital if related to the issuance of an equity instrument.

Recently Adopted Accounting Standards

In September of 2025, the FASB issued ASU 2025-07: Derivates and Hedging (ASC 815) and Revenue from Contracts with Customers (ASC 606). This ASU expands the scope exceptions in the derivative guidance to exclude certain non-exchange-trade contracts with underlyings based on the operations or activities of one of the parties to the contract, including the occurrence or nonoccurrence of an event specific to those operations or activities. The ASU also clarifies that share-based noncash consideration received from a customer in exchange for goods or services should be accounted for as noncash consideration under ASC 606 unless and until the entity’s rights to receive or retain such consideration becomes unconditional. The Company early adopted the ASU at the beginning of fiscal year 2026, using the prospective method. The adoption of this new accounting standard was applied to the evaluation of the senior secured term loan that was executed during the first quarter.

Recent Accounting Pronouncements

In November 2024, the FASB issued 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires entities to disclose additional information about specific expense categories in the notes to the financial statements. ASU 2024-03 is effective for annual periods beginning after December 15, 2026 and for interim periods within fiscal years

beginning after December 15, 2027, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively to the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its unaudited condensed consolidated financial statements and related disclosures.

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that the Company adopts as of the specified effective date. Unless otherwise discussed, the Company does not believe that the adoption of recently issued standards have or may have a material impact on its unaudited condensed consolidated financial statements or disclosures.

License Agreements (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
License Agreements (Details) - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Oct. 31, 2025	Jan. 31, 2025	May 31, 2021	Oct. 31, 2020
2021 Xencor Agreement
Nature of Business
Regulatory milestone payments							$ 75.0
Sales milestone payments							385.0
License and option agreements, Food and Drug Administration market authorization payable							10.0
License and option agreements, Food and Drug Administration market authorization milestone payments made	$ 10.0
License and option agreements, Food and Drug Administration market approval payable							$ 20.0
Viridian Agreement
Nature of Business
Sales milestone payments								$ 21.0
Contract manufacturing organization costs recognized	0.0	$ 0.0	$ 0.0	$ 0.0
Reimbursable costs		$ 0.2		$ 0.2
Development milestone expense payable						$ 21.0
InnoCare Pharma Inc
Nature of Business
Non-refundable cash payment					$ 35.0
Number of shares agreed to be issued					5,000,000
Amount of contingent payment payable upon on occurrence of specified events					$ 25.0
Number of shares agreed to be issued upon on occurrence of specified events					2,000,000
Term milestone payments					$ 20.0
Future regulatory and commercial milestones payable					723.0
Development, regulatory and commercial milestones payable					636.0
Regulatory milestones payable					$ 20.0
Regulatory milestone payments made	20.0
Contract manufacturing organization costs recognized	0.7		1.9
Reimbursable costs	$ 1.4		$ 2.2

License Agreements

6 Months Ended

Jun. 30, 2026

License Agreements

License Agreements

8.License Agreements

License Agreements with Xencor, Inc.

2020 Xencor Agreement

In September 2020, the Company entered into a license agreement (the “2020 Xencor Agreement”) with Xencor, Inc. (“Xencor”), under which the Company is required to pay Xencor tiered royalties on annual net sales of successfully commercialized products, including ZB002 and ZB004. The royalty percentage rates vary by geographic areas as defined in the 2020 Xencor Agreement and range from the mid-single digits to mid-teens. The Company is also obligated to reimburse Xencor for third-party costs incurred for certain patent filings, prosecution and maintenance as further specified in the 2020 Xencor Agreement.

2021 Xencor Agreement

In May 2021, the Company entered into a license agreement with Xencor (the “2021 Xencor Agreement”), under which the Company obtained an exclusive, royalty-bearing, sublicensable worldwide license to research, develop, manufacture, market and sell obexelimab. The Company is obligated to make regulatory milestone payments up to $75.0 million, including $10.0 million for FDA marketing authorization submission which was achieved during the three months ended June 30, 2026 and $20.0 million for marketing approval, and one-time sales milestone payments up to $385.0 million upon achieving milestone events of net sales in a given calendar year in the territory equal to certain threshold amounts. In addition, the Company is required to pay Xencor tiered royalties on annual net sales of successfully commercialized products utilizing obexelimab, with the royalty percentages varying based on regions and ranging from the mid-single digits to the mid-teens.

During the three months ended June 30, 2026, the Company completed the FDA marketing authorization submission and made a $10.0 million milestone payment which was recorded as acquired in-process research and development expense. During three and six months ended June 30, 2026 and 2025, the Company did not record any reimbursable patent-related costs.

License Agreement with Viridian Therapeutics, Inc.

In October 2020, the Company entered into a license agreement with Viridian (the “Viridian Agreement”) to obtain an exclusive, royalty-bearing, sublicensable license to research, develop, manufacture, market and sell certain antibody product candidates based on Viridian’s proprietary technology. The Company’s license rights are limited to non-oncology indications and are limited to China, Hong Kong, Macau and Taiwan (“Zenas Territories”). The Viridian Agreement, as amended, obligates the Company to make payments to Viridian, totaling $21.0 million, based on achievement of certain specified development and sales milestones, and royalties on net sales.

In January 2025, the Company entered the Zai License Agreement under which the Company granted Zai an exclusive sublicense to develop, manufacture and commercialize ZB001 and related programs in greater China. In connection with the Zai License Agreement, the Company assigned the Viridian Supply Agreement to Zai. For additional information on the Zai License Agreement, please see License Agreement with Zai Lab (Hong Kong) Limited in Note 7 – License and Collaboration Revenue to these unaudited condensed consolidated financial statements.

During the three and six months ended June 30, 2026 and 2025, the Company did not incur expenses related to Viridian contract manufacturing organization (“CMO”) costs. Viridian has agreed to reimburse the Company for certain services the Company performs on Viridian’s behalf, with reimbursements being recorded as a reduction in research and development expenses. During the three and six months ended June 30, 2026, the Company did not incur any reimbursable expenses. During the three and six months ended June 30, 2025, the Company recorded an immaterial amount and $0.2 million in reimbursable expenses, respectively. Additionally, during the six months ended June 30, 2026 and 2025, the Company did not achieve any milestones.

License Agreement with InnoCare Pharma Inc.

In October 2025, the Company entered into a License Agreement (the “InnoCare License Agreement”) with InnoCare Pharma Inc. (“InnoCare”). Under the InnoCare License Agreement, InnoCare granted the Company exclusive rights to develop, manufacture, and commercialize: i) orelabrutinib, in the multiple sclerosis (“MS”) field worldwide, and in all non-oncology indications outside greater China and Brunei, Burma, Cambodia, Timor-Leste, Indonesia, Laos, Malaysia, Philippines, Singapore, Thailand and Vietnam (“Southeast Asia”), ii) ZB021 (an IL-17AA/AF inhibitor) in all fields of use worldwide, excluding greater China and Southeast Asia and iii) ZB022 (a TYK2 inhibitor) in all fields of use worldwide. The Company also obtained certain non-exclusive rights to perform development and manufacturing activities in greater China and Southeast Asia to support each program in its respective licensed territories.

Pursuant to the InnoCare License Agreement, the Company made one-time non-refundable upfront cash payments totaling $35.0 million and issued 5,000,000 shares of common stock to InnoCare (“InnoCare Shares”) in exchange for these rights.

The Company is also required to make an additional one-time non-refundable cash payment of $25.0 million and issue an additional 2,000,000 shares of common stock to InnoCare upon the achievement of a specified development milestone related to Zenas’ Phase 3 clinical trial for orelabrutinib in any indication other than primary progressive MS, or by March 31, 2026, upon the occurrence of certain specified events, whichever comes first (the “Near-term Milestone”). In addition, the Company has agreed to make one-time, potential near-term milestone payments of $20.0 million each, upon the achievement of certain regulatory milestones for ZB021 and ZB022 (the “Regulatory Milestones”). During the three months ended June 30, 2026, the Company achieved the ZB021 Regulatory Milestone and made a payment of $20.0 million, which was recorded as acquired in-process research and development expense.

The Company is further obligated to pay future regulatory and commercial milestones of up to $723.0 million related to orelabrutinib, and future development, regulatory, and commercial milestones of up to $636.0 million for ZB021, and $656.0 million for ZB022, inclusive of the $20.0 million Regulatory Milestone for ZB022 specified above, if certain milestones are successfully achieved. In addition, the Company is obligated to pay royalties on net sales at rates ranging from high-single digits to high-teens for orelabrutinib, and mid-single digits to mid-teens for the preclinical compounds.

Under the InnoCare License Agreement, the Company is obligated to reimburse InnoCare for certain clinical trial startup costs and Investigational New Drug (“IND”) enabling activities which were incurred prior to and after the effective date of the agreement. During the three and six months ended June 30, 2026, the Company incurred $0.7 million and $1.9 million of expense, respectively. During the three and six months ended June 30, 2026, the Company made payments of $1.4 million and $2.2 million to InnoCare related to the acquired programs, respectively.

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2026
Summary of Significant Accounting Policies
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying condensed consolidated financial statements include the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts, transactions, and balances have been eliminated in consolidation. The accompanying condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited financial statements and in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2026, and the results of operations and its cash flows for the three and six months ended June 30, 2026 and 2025. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2026 and 2025 are not necessarily indicative of the results to be expected for the year ending December 31, 2026, any other interim periods, or any future year or period. These interim financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2025, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K as filed with the SEC, on March 16, 2026.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses, and related disclosures. The Company bases its estimates on historical experience, known trends and other market-specific factors or other relevant factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis using such factors and adjusts those estimates and assumptions as facts and circumstances dictate. Actual results may differ from those estimates or assumptions. Significant estimates in these unaudited condensed consolidated financial statements include estimates made in connection with accrued research and development expenses, stock-based compensation, valuations of embedded features within its senior secured term loan and the liability related to the sale of future royalties including the estimation of future payments and the related non-cash interest expense. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgement. As of the date of the issuance of these unaudited condensed consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgements or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s financial statements.
Embedded Derivative Financial Instruments	Embedded Derivative Financial Instruments The Company evaluates its financial instruments, including its convertible senior notes and senior secured term loan to determine if such instruments are derivatives or contain features that qualify as embedded derivatives in accordance with ASC 815 “Derivatives and Hedging.” ASC 815 generally provides three criteria that, if met, require companies to bifurcate embedded features from their host instruments and account for them as free-standing derivative financial instruments. The three criteria include circumstances in which (a) the economic characteristics and risks of the embedded derivative instrument are not clearly and closely related to the economic characteristics and risks of the host contract, (b) the hybrid instrument that embodies both the embedded derivative instrument and the host contract is not remeasured at fair value under otherwise applicable generally accepted accounting principles with changes in fair value reported in earnings as they occur, and (c) a separate instrument with the same terms as the embedded derivative would be considered a derivative instrument. If liability accounting is required, the Company’s derivative instruments are recorded at fair value with an offsetting amount recorded as a debt discount, which offsets the carrying amount of the debt. The derivative is revalued at the end of each reporting period and any change in fair value is recorded as a gain or loss in the statement of operations. The debt discount is amortized through interest expense over the life of the debt using the straight-line method.
Convertible Instruments	Convertible Instruments When the Company issues debt with a conversion feature, in accordance with ASC 815, “Derivatives and Hedging” it must first assess whether the conversion feature meets the requirements to be treated as a derivative. An embedded equity-linked component that meets the definition of a derivative does not have to be separated from the host instrument if the component qualifies for the scope exception for certain contracts involving an issuer’s own equity. The scope exception applies if the contract is both (a) indexed to its own stock; and (b) classified in stockholders’ equity in its balance sheet.
Debt and Debt Issuance Costs	Debt and Debt Issuance Costs Debt issuance costs and expenses paid by the Company to its lenders are presented on the unaudited condensed consolidated balance sheet as a direct deduction from the related liability. Debt issuance costs represent costs that are paid directly to third parties and directly attributable to the issuance of a debt or equity instrument, which includes lender fees, legal expenses and other direct costs. These costs are amortized as a non-cash component of interest expense using the effective interest method over the term of the debt. Costs and discounts are presented as a reduction of the related debt in the accompanying balance sheet if related to the issuance of debt or presented as a reduction of additional paid in capital if related to the issuance of an equity instrument.
Recently Adopted Accounting Standards and Recent Accounting Pronouncements	Recently Adopted Accounting Standards In September of 2025, the FASB issued ASU 2025-07: Derivates and Hedging (ASC 815) and Revenue from Contracts with Customers (ASC 606). This ASU expands the scope exceptions in the derivative guidance to exclude certain non-exchange-trade contracts with underlyings based on the operations or activities of one of the parties to the contract, including the occurrence or nonoccurrence of an event specific to those operations or activities. The ASU also clarifies that share-based noncash consideration received from a customer in exchange for goods or services should be accounted for as noncash consideration under ASC 606 unless and until the entity’s rights to receive or retain such consideration becomes unconditional. The Company early adopted the ASU at the beginning of fiscal year 2026, using the prospective method. The adoption of this new accounting standard was applied to the evaluation of the senior secured term loan that was executed during the first quarter. Recent Accounting Pronouncements In November 2024, the FASB issued 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires entities to disclose additional information about specific expense categories in the notes to the financial statements. ASU 2024-03 is effective for annual periods beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively to the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on its unaudited condensed consolidated financial statements and related disclosures. From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that the Company adopts as of the specified effective date. Unless otherwise discussed, the Company does not believe that the adoption of recently issued standards have or may have a material impact on its unaudited condensed consolidated financial statements or disclosures.

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

+ References

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+ Details

Royalty Obligation (Tables)

6 Months Ended

Jun. 30, 2026

Royalty Obligation

Schedule of activity within liability account

The following table shows the activity within the liability account of the arrangement (in thousands):



	Period from inception to June 30, 2026
Proceeds from royalty obligation	$	75,000
Issuance costs		(3,691)
Interest expense related to royalty obligation		20,428
Royalty obligation as of June 30, 2026	$	91,737
Effective interest rate		32.3%

Long - Term Obligations - Senior Secured Term Loan - Amortization of debt costs (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026
Debt Instrument [Line Items]
Total interest expense	$ 1,720	$ 2,088
Senior Secured Term Loan
Debt Instrument [Line Items]
Amortization of debt discounts and issuance costs	160	194
PIK interest expense (applied to term loan principal balance)	1,560	1,894
Total interest expense	$ 1,720	$ 2,088

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Nature of Business (Details) $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended
Nature of Business (Details) $ in Thousands	Feb. 28, 2026 USD ($)	Jun. 30, 2026 USD ($)	Mar. 31, 2026 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Jun. 30, 2026 USD ($) segment	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Nature of Business
Number of operating segments \| segment						1
Net loss	$ 111,500	$ 111,456	$ 80,987	$ 52,223	$ 33,573	$ 192,443	$ 85,796
Accumulated deficit		957,571				957,571		$ 765,128
Cash, cash equivalents and investments		$ 673,900				$ 673,900

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Reference 19: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
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Reference 38: http://www.xbrl.org/2003/role/disclosureRef
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Reference 39: http://www.xbrl.org/2003/role/disclosureRef
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Reference 41: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Section S99
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Reference 42: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 43: http://www.xbrl.org/2003/role/disclosureRef
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Reference 44: http://www.xbrl.org/2003/role/disclosureRef
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Reference 46: http://www.xbrl.org/2003/role/disclosureRef
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Reference 47: http://www.xbrl.org/2003/role/disclosureRef
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Reference 48: http://www.xbrl.org/2003/role/disclosureRef
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Reference 49: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Accrued Expenses
External research, development and manufacturing expenses	$ 43,632	$ 38,855
Employee compensation and benefits	9,836	13,080
Professional and consultant fees	1,702	1,500
Interest expense on convertible senior notes	1,465
Income taxes payable		118
Other	771	870
Total accrued expenses	$ 57,406	$ 54,423

Fair Value Measurements - Fair Value Transfers (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Fair Value Measurements
Assets - Transfer from level 1 to 2			$ 0		$ 0
Assets - Transfer from level 2 to 1			0		0
Assets - Transfer into level 3			0		0
Liabilities - Transfer from level 1 to 2			0		0
Liabilities - Transfer from level 2 to 1			0		0
Liabilities - Transfer into level 3			0		$ 0
Realized gain (loss) recognized on the sale or maturity of available-for-sale	$ 0	$ 0	$ 0	$ 0
Minimum
Fair Value Measurements
Remaining contractual maturities			1 month
Maximum
Fair Value Measurements
Remaining contractual maturities			16 months

Fair Value Measurements - Valuation Techniques (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Short-term investments:
Short-term investments	$ 477,312	$ 249,823
Commercial paper
Short-term investments:
Short-term investments	24,217	5,959
Corporate debt securities
Short-term investments:
Short-term investments	95,550	45,766
Government securities
Short-term investments:
Short-term investments	357,545	198,098
Carrying value
Long-term investments:
Total assets	673,889	360,464
Carrying value \| Cash
Assets:
Assets	115,202	13,038
Carrying value \| Money market funds
Assets:
Assets	81,375	97,603
Carrying value \| Commercial paper
Short-term investments:
Short-term investments	24,217	5,959
Carrying value \| Corporate debt securities
Short-term investments:
Short-term investments	78,902	44,299
Long-term investments:
Long-term investments	16,648	1,467
Carrying value \| Government securities
Short-term investments:
Short-term investments	343,430	182,293
Long-term investments:
Long-term investments	14,115	15,805
Estimate of fair value measurement \| Level 1
Long-term investments:
Total assets	554,122	308,739
Estimate of fair value measurement \| Level 1 \| Cash
Assets:
Assets	115,202	13,038
Estimate of fair value measurement \| Level 1 \| Money market funds
Assets:
Assets	81,375	97,603
Estimate of fair value measurement \| Level 1 \| Government securities
Short-term investments:
Short-term investments	343,430	182,293
Long-term investments:
Long-term investments	14,115	15,805
Estimate of fair value measurement \| Level 2
Long-term investments:
Total assets	119,767	51,725
Estimate of fair value measurement \| Level 2 \| Commercial paper
Short-term investments:
Short-term investments	24,217	5,959
Estimate of fair value measurement \| Level 2 \| Corporate debt securities
Short-term investments:
Short-term investments	78,902	44,299
Long-term investments:
Long-term investments	$ 16,648	$ 1,467

Other Non-Current Assets

6 Months Ended

Jun. 30, 2026

Other Non-Current Assets

Other Non-Current Assets

4.Other Non-Current Assets

Other non-current assets consisted of the following (in thousands):


	June 30, 2026			December 31, 2025
Clinical trial deposits	$	15,716		$	12,882
Deferred offering costs		486			709
Other		87			218
Total other assets	$	16,289		$	13,809

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2026

Stock-Based Compensation

Schedule of stock option activity and related information


	Number of Shares		Weighted - Average Exercise Price			Weighted-Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding - December 31, 2025	10,675,615		$	13.46		8.60		$	243,979
Granted	2,299,700		$	19.35
Exercised	(103,592)		$	11.33				$	1,204
Forfeited or cancelled	(226,323)		$	13.76
Outstanding - June 30, 2026	12,645,400		$	14.54		8.26		$	139,386
Options vested and exercisable as of June 30, 2026	4,796,080		$	12.35		7.50		$	62,478
Options vested and expected to vest as of June 30, 2026	12,645,400		$	14.54		8.26		$	139,386

Summary of company's RSU activity


	Number of Shares		Weighted - Average Grant Date Fair Value
Unvested as of December 31, 2025	599,675	$	14.23
Granted	848,100	$	19.49
Vested	(119,545)	$	11.94
Forfeited	(64,536)	$	12.81
Unvested as of June 30, 2026	1,263,694	$	18.05

Schedule of stock-based compensation expense as reflected in consolidated statements of operations

The Company recognized stock-based compensation expense related to the issuance of equity awards to employees and directors in the unaudited condensed consolidated statement of operations as follows (in thousands):


		Three Months Ended June 30,				Six Months Ended June 30,
		2026		2025		2026		2025
Research and development	$	3,861	$	2,113	$	6,957		3,694
General and administrative		4,758		3,932		10,857		7,737
Total stock-based compensation expense	$	8,619	$	6,045	$	17,814	$	11,431

Long - Term Obligations - Senior Secured Term Loan (Details)	1 Months Ended	3 Months Ended	6 Months Ended
	Mar. 31, 2026 USD ($) tranche	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)
Senior Secured Term Loan
Debt Instrument [Line Items]
Loan facility	5 years
Maximum borrowing capacity	$ 250,000,000
Number of tranches \| tranche	5
Number of committed tranches \| tranche	2
Number of tranches at discretion \| tranche	3
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:SecuredOvernightFinancingRateSofrMember
Interest floor rate (as a percent)	3.25%
Basis spread on variable rate	5.75%
Proceeds from royalty obligation			$ 72,000,000
Repayment of principal or interest		$ 0	0
Deferred debt discounts and issuance costs	$ 3,000,000	$ 2,834,000	$ 2,834,000
Effective interest rate		10.99%
Number of equal period repayment	4
Senior Secured Term Loan \| Minimum
Debt Instrument [Line Items]
Exit consideration fee - Percentage of multiplier on prepaid or repaid principal amount (as a percent)	1.00%
Senior Secured Term Loan \| Maximum
Debt Instrument [Line Items]
Exit consideration fee - Percentage of multiplier on prepaid or repaid principal amount (as a percent)	2.00%
Senior Secured Term Loan \| First 24 months following the Tranche A Loan funding date
Debt Instrument [Line Items]
Percentage of interest to be paid-in-kind (as a percent)	100.00%
Senior Secured Term Loan \| Immediately following Tranche A loan fund date till satisfaction of Tranche B/A approval condition
Debt Instrument [Line Items]
Minimum liquidity to be maintain	$ 50,000,000
Senior Secured Term Loan \| If prepayment occurs prior to the 3rd year anniversary
Debt Instrument [Line Items]
Required prepayment premium - Percentage of multiplier on prepaid principal (as a percent)	3.00%
Senior Secured Term Loan \| If prepayment occurs after 3rd year but prior to the 4th year anniversary
Debt Instrument [Line Items]
Required prepayment premium - Percentage of multiplier on prepaid principal (as a percent)	2.00%
Senior Secured Term Loan \| If prepayment occurs after 4rd year anniversary but prior to the term of loan maturity date
Debt Instrument [Line Items]
Required prepayment premium - Percentage of multiplier on prepaid principal (as a percent)	1.00%
Senior Secured Term Loan \| If aggregated principal outstanding of Term Loans exceeds $200 million
Debt Instrument [Line Items]
Debt Covenant - Minimum trailing twelvemonth consolidated net revenue threshold	$ 200,000,000
Term Loan (Tranche A)
Debt Instrument [Line Items]
Aggregate amount of loan funded	$ 75,000,000
Percentage of funding fee (as a percent)	2.00%
Payment of funding fee	$ 1,500,000
Term Loan (Tranche B)
Debt Instrument [Line Items]
Aggregate amount of loan funded	50,000,000
Maximum additional borrowing capacity	$ 25,000,000
Percentage of funding fee (as a percent)	2.00%
Term Loan (Tranche C)
Debt Instrument [Line Items]
Aggregate amount of loan funded	$ 25,000,000
Percentage of funding fee (as a percent)	1.00%
Term Loan (Tranche D)
Debt Instrument [Line Items]
Aggregate amount of loan funded	$ 50,000,000
Percentage of funding fee (as a percent)	1.00%
Term Loan (Tranche E)
Debt Instrument [Line Items]
Aggregate amount of loan funded	$ 50,000,000
Percentage of funding fee (as a percent)	1.00%

Long - Term Obligations - Convertible debt - Amortization of Debt Costs (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026
Debt Instrument [Line Items]
Total interest expense	$ 1,720	$ 2,088
2.50% convertible senior notes due 2032
Debt Instrument [Line Items]
Cash interest expense		1,465
Amortization of commissions and offering costs		280
Total interest expense		$ 1,745

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Long - Term Obligations (Tables)

6 Months Ended

Jun. 30, 2026

Senior Secured Term Loan

Debt Instrument [Line Items]

Schedule of senior secured term loan

The following table reflects the Company’s senior secured term loan as of June 30, 2026 (in thousands):


	June 30,
	2026
Outstanding principal balance	$	75,000
Accumulated PIK interest applied to term loan balance		1,894
Unamortized debt discounts and issuance costs		(2,834)
Carrying value	$	74,060

Schedule of interest expense of long-term debt obligations

Interest expense in relation to the Loan Agreement, including amortization of debt discounts and issuance costs amortization is as follows (in thousands):


	For the three months ended June 30,		For the six months ended June 30,
	2026		2026
Amortization of debt discounts and issuance costs	$	160	$	194
PIK interest expense (applied to term loan principal balance)		1,560		1,894
Total interest expense	$	1,720	$	2,088

2.50% convertible senior notes due 2032

Debt Instrument [Line Items]

Schedule of outstanding balance of the Convertible Notes

The outstanding balance of the Convertible Notes consisted of the following as of June 30, 2026 (in thousands):


	June 30,
	2026
Outstanding principal balance	$	230,000
Unamortized commissions and offering costs		(7,044)
Carrying value	$	222,956

Schedule of interest expense of long-term debt obligations

Interest expense in relation to the Convertible Notes, including amortization of commissions and offering costs is as follows (in thousands):


	For the three and six months ended June 30,
	2026
Cash interest expense	$	1,465
Amortization of commissions and offering costs		280
Total interest expense	$	1,745

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
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+ Details

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Jun. 30, 2026
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false

Other Non-Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Other Non-Current Assets
Clinical trial deposits	$ 15,716	$ 12,882
Deferred offering costs	486	709
Other	87	218
Total other assets	$ 16,289	$ 13,809

Royalty Obligation - Activity of liability account arrangement (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Sep. 30, 2025	Jun. 30, 2026
Royalty Obligation
Interest expense related to royalty obligation		$ 13,100
Royalty obligation
Royalty Obligation
Proceeds from royalty obligation	$ 75,000	75,000
Issuance costs	$ (3,700)	(3,691)
Interest expense related to royalty obligation		20,428
Royalty obligation as of March 31, 2026		$ 91,737
Effective interest rate		32.30%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Stock-Based Compensation

6 Months Ended

Jun. 30, 2026

Stock-Based Compensation

Stock-Based Compensation

11.Stock-Based Compensation

2020 Plan

In August 2020, the Company’s sole director adopted the 2020 Equity Incentive Plan (the “2020 Plan”). Upon effectiveness of the 2024 Plan (as defined below), the Company ceased granting additional awards under the 2020 Plan and the remaining available shares for future grants were transferred to the 2024 Plan. The 2020 Plan allowed the Company to grant stock options, restricted stock awards, restricted stock units (“RSUs”) and other stock-based awards to employees, officers, directors and consultants of the Company and its subsidiaries. As of June 30, 2026, 3,092,255 shares of stock options were issued and outstanding under the 2020 Plan.

2024 Plan

In September 2024, the Company’s board of directors (the “Board”) adopted the 2024 Equity Incentive Plan (the “2024 Plan”), which became effective immediately prior to the effectiveness of the registration statement for the Company’s IPO. The 2024 Plan provides for the award of incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, unrestricted stock, restricted stock units and other stock-based awards.

The number of shares reserved and available for issuance under the 2024 Plan will automatically increase each January 1, beginning on January 1, 2025 through January 1, 2034, by the number of shares equal to the lesser of (i) five percent of the aggregate number of shares of common stock outstanding as of such date, and (ii) a number of shares as may be determined by the Board on or prior to such date. On January 1, 2026, the number of shares of common stock available for issuance under the Company’s 2024 Plan increased to 3,156,138. As of June 30, 2026, 1,028,297 shares of common stock were available for issuance under the 2024 Plan.

2026 Inducement Plan

In December 2025, the Company’s Board adopted the 2026 Inducement Plan (the “2026 Inducement Plan”), which became effective December 10, 2025. The 2026 Inducement Plan provides for awards of non-qualified stock options and other awards under the 2026 Inducement Plan to persons not previously an employee or director of the Company, or following a bona fide period of non-employment, as an inducement material to such persons entering the employment of the Company. The grants constitute “employment inducement grants” in accordance with Rule 5635(c)(4) of the Nasdaq Listing Rules and are issued outside of the 2024 Plan. The inducement grants include non-statutory options to purchase shares of the Company’s common stock and RSUs. The inducement grants have terms and conditions consistent with those set forth in the 2024 Plan and vest under the same respective vesting schedules as stock options and RSUs granted under the 2024 Plan. The Company initially reserved 1,000,000 shares of common stock for the issuance of awards under the 2026 Inducement Plan. As of June 30, 2026, 270,900 shares of common stock were available for issuance under the 2026 Inducement Plan.

Stock Options

The Company has granted stock-based awards with either service or performance based vesting conditions. Compensation expense related to awards to employees and directors with service based vesting conditions is recognized on a straight-line basis based on the grant date fair value over the associated service period of the award, which is generally the vesting term. Compensation expense related to awards to employees with performance based vesting conditions is recognized based on the grant date fair value once the achievement of the performance condition is probable.

From time to time, the Company grants equity awards to newly hired employees as an inducement to enter into employment with the Company. The grants constitute "employment inducement grants" in accordance with Rule 5635(c)(4) of the Nasdaq Listing Rules and are issued outside of the 2024 and 2026 Plans (the “Individual Inducement Grants”). The Individual Inducement Grants include non-statutory stock options to purchase shares of the Company's common stock and RSUs. The Individual Inducement Grants are granted under individual inducement agreements and have terms and conditions consistent with those set forth under the 2024 Plan and vest under the same respective vesting schedules as stock option awards granted under the 2024 Plan. The Individual Inducement Grants are included in the stock option award tables below. As of June 30, 2026, the Company granted 1,062,000 non-statutory stock options as Individual Inducement Grants, which were awarded during the year ended December 31, 2025. The Company did not grant any stock options or RSUs as Individual Inducement Grants during the three or six months ended June 30, 2026.

The following table presents a summary of the Company’s stock option activity and related information:


	Number of Shares		Weighted - Average Exercise Price			Weighted-Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding - December 31, 2025	10,675,615		$	13.46		8.60		$	243,979
Granted	2,299,700		$	19.35
Exercised	(103,592)		$	11.33				$	1,204
Forfeited or cancelled	(226,323)		$	13.76
Outstanding - June 30, 2026	12,645,400		$	14.54		8.26		$	139,386
Options vested and exercisable as of June 30, 2026	4,796,080		$	12.35		7.50		$	62,478
Options vested and expected to vest as of June 30, 2026	12,645,400		$	14.54		8.26		$	139,386

The aggregate intrinsic value of the stock options outstanding is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock for those stock options that had an exercise price lower than the fair value of the Company’s common stock as of the measurement date of June 30, 2026.

Restricted Stock Units

The Company has granted RSUs that are subject to time-based vesting conditions, that vest equally over four years, assuming continued employment. RSUs with time-based vesting conditions are valued on the grant date using the grant date market value price of the underlying shares of the Company’s common stock. The following table summarizes the Company’s RSU activity:


	Number of Shares		Weighted - Average Grant Date Fair Value
Unvested as of December 31, 2025	599,675	$	14.23
Granted	848,100	$	19.49
Vested	(119,545)	$	11.94
Forfeited	(64,536)	$	12.81
Unvested as of June 30, 2026	1,263,694	$	18.05

The fair value of RSUs vested during the three and six months ended June 30, 2026 was $2.2 million.

As of June 30, 2026, unrecognized stock-based compensation expense was $109.6 million, which is expected to be recognized over a weighted-average period of 3.0 years.


		Three Months Ended June 30,				Six Months Ended June 30,
		2026		2025		2026		2025
Research and development	$	3,861	$	2,113	$	6,957		3,694
General and administrative		4,758		3,932		10,857		7,737
Total stock-based compensation expense	$	8,619	$	6,045	$	17,814	$	11,431

Employee Stock Purchase Plan

In September 2024, the Board adopted the 2024 Employee Stock Purchase Plan (the “ESPP”), which became effective immediately prior to the effectiveness of the registration statement for the Company’s IPO. The number of shares of common stock available under the ESPP will automatically increase on January 1st of each year, beginning on January 1, 2025 through January 1, 2034, by the number of shares equal to the lesser of (i) one percent of the aggregate number of shares of common stock outstanding as of such date, and (ii) a number of shares as may be determined by the Board on or prior to such date, up to a maximum of 1,000,000 shares in the aggregate per year. On January 1, 2026, the number of shares of common stock authorized for issuance under the ESPP increased to 1,317,977. As of June 30, 2026, 1,273,608 shares were available for future issuance under the ESPP. During the three months ended June 30, 2026, there were no issuances under the ESPP. During the six months ended June 30, 2026, there were 44,369 shares issued under the ESPP.

Long - Term Obligations - Convertible Senior Notes (Details)	1 Months Ended		3 Months Ended	6 Months Ended
	Apr. 30, 2026 USD ($)	Mar. 31, 2026 USD ($) D $ / shares	Jun. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)
Royalty Obligation
Payments of debt issuance costs				$ 1,934,000
Interest expense on senior secured term loan			$ 1,720,000	$ 2,088,000
Maximum
Royalty Obligation
Conversion ratio				50
2.50% convertible senior notes due 2032
Royalty Obligation
Aggregate amount of loan funded	$ 30,000,000	$ 200,000,000
Interest floor rate (as a percent)		2.50%
Threshold percentage of stock price trigger		130.00%
Threshold trading days for attaining stock price trigger \| D		20
Threshold consecutive trading days for attaining stock price trigger \| D		30
Number of business days for attaining average trading price \| D		5
Number of consecutive business days for attaining average trading price \| D		10
Average trading price percentage of average conversion value		98.00%
Scheduled trading day \| D		26
Minimum principal amount outstanding unredeemed for redemption		$ 75,000,000
Conversion ratio		37.7358
Conversion price \| $ / shares		$ 26.5
Maximum share price threshold for conversion ratio adjustment \| $ / shares		160
Minimum share price threshold for conversion ratio adjustment \| $ / shares		$ 20
Number of volume-weighted average price (VWAP) for debt settlements \| D		25
Payments of debt issuance costs	$ 900,000	$ 7,300,000
Effective interest rate			3.07%	3.07%
Debt default cure period		60 days
Cross default threshold amount		$ 30,000,000
Fair value of debt notes			$ 275,500,000	$ 275,500,000
Notes converted				0
Notes redeemed				$ 0
2.50% convertible senior notes due 2032 \| Maximum
Royalty Obligation
Conversion ratio		50

Segment Information (Details) $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended
Segment Information (Details) $ in Thousands	Feb. 28, 2026 USD ($)	Jun. 30, 2026 USD ($)	Mar. 31, 2026 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Jun. 30, 2026 USD ($) segment	Jun. 30, 2025 USD ($)
Segment Information
Number of reportable segment \| segment						1
Revenue		$ 1,000				$ 1,000	$ 10,000
Research and development expenses		62,913		$ 43,027		123,352	77,942
General and administrative		15,746		12,136		32,657	24,551
Stock-based compensation		8,619		6,045		17,814	11,431
Net loss	$ (111,500)	(111,456)	$ (80,987)	(52,223)	$ (33,573)	(192,443)	(85,796)
Zenas BioPharma (HK) Limited
Segment Information
Revenue		1,000		0		1,000	10,000
Single Reportable Segment
Segment Information
Revenue		1,000				1,000	10,000
General and administrative		10,988		8,204		21,800	16,814
Acquired in-process research and development		30,000				30,000
Stock-based compensation		8,619		6,045		17,814	11,431
Other segment items		3,797		(2,940)		7,434	(6,697)
Net loss		$ (111,456)		$ (52,223)		$ (192,443)	$ (85,796)
Other segment items, description		Other segment items consist of other (income) expense, net, and income tax (benefit) provision. Other (income) expense, net consists of interest income, interest expense related to the royalty obligation, the senior secured term loan and convertible senior note as well as realized and unrealized gains and losses on foreign currency transactions		Other segment items consist of other (income) expense, net, and income tax (benefit) provision. Other (income) expense, net consists of interest income, interest expense related to the royalty obligation, the senior secured term loan and convertible senior note as well as realized and unrealized gains and losses on foreign currency transactions		Other segment items consist of other (income) expense, net, and income tax (benefit) provision. Other (income) expense, net consists of interest income, interest expense related to the royalty obligation, the senior secured term loan and convertible senior note as well as realized and unrealized gains and losses on foreign currency transactions	Other segment items consist of other (income) expense, net, and income tax (benefit) provision. Other (income) expense, net consists of interest income, interest expense related to the royalty obligation, the senior secured term loan and convertible senior note as well as realized and unrealized gains and losses on foreign currency transactions
Single Reportable Segment \| Obexelimab
Segment Information
Research and development expenses		$ 29,394		$ 29,894		$ 61,154	$ 53,254
Single Reportable Segment \| Orelabrutinib
Segment Information
Research and development expenses		11,206				21,307
Single Reportable Segment \| Other programs (ZB002, ZB004, ZB014, ZB021 & ZB022)
Segment Information
Research and development expenses		1,458		400		2,026	736
Single Reportable Segment \| Partnered regional programs (ZB001 & ZB005)
Segment Information
Research and development expenses		(24)		(137)		(24)	(37)
Single Reportable Segment \| Unallocated
Segment Information
Research and development expenses		$ 17,018		$ 10,757		$ 31,932	$ 20,295

Stock-Based Compensation - Stock Options (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2026 USD ($) $ / shares shares	Dec. 31, 2025 USD ($) $ / shares shares
Number of Shares
Balance outstanding at beginning of year (in shares) \| shares	10,675,615
Granted (in shares) \| shares	2,299,700
Exercised (in shares) \| shares	(103,592)
Forfeited or cancelled (in shares) \| shares	(226,323)
Balance outstanding at end of year (in shares) \| shares	12,645,400	10,675,615
Options vested and exercisable at end of year (in shares) \| shares	4,796,080
Options vested and expected to vest end of year (in shares) \| shares	12,645,400
Weighted - Average Exercise Price
Balance outstanding at beginning of year (in dollars per share) \| $ / shares	$ 13.46
Granted (in dollars per share) \| $ / shares	19.35
Exercised (in dollars per share) \| $ / shares	11.33
Forfeited or cancelled (in dollars per share) \| $ / shares	13.76
Balance outstanding at end of year (in dollars per share) \| $ / shares	14.54	$ 13.46
Options vested and exercisable at end of year (in dollars per share) \| $ / shares	12.35
Options vested and expected to vest at end of year (in dollars per share) \| $ / shares	$ 14.54
Weighted-Average Remaining Contractual Term (In years)
Balance outstanding at end of year (in years)	8 years 3 months 3 days	8 years 7 months 6 days
Options vested and exercisable at end of year (in years)	7 years 6 months
Options vested and expected to vest at end of year (in years)	8 years 3 months 3 days
Aggregate Intrinsic Value
Balance at beginning of year \| $	$ 243,979
Exercised \| $	1,204
Balance outstanding at end of year \| $	139,386	$ 243,979
Options vested and exercisable at end of year \| $	62,478
Options vested and expected to vest at end of year \| $	139,386
Employee Stock Option
Aggregate Intrinsic Value
Unrecognized compensation cost related to unvested stock options \| $	$ 109,600
Weighted average period over which unrecognized compensation cost is expected to be recognized	3 years

Commitments and Contingencies (Details) $ in Millions	Jun. 30, 2026 USD ($)
Commitments and Contingencies
Contract payment obligation	$ 15.8

Common Stock - Reserved for Issuance (Details)	6 Months Ended
Common Stock - Reserved for Issuance (Details)	Jun. 30, 2026 shares	Dec. 31, 2025 shares
Common Stock
Options to purchase common stock	12,645,400	10,675,615
Remaining shares reserved for future issuance	1,299,197	431,863
RSUs	1,263,694	599,675
Employee stock purchase plan	1,273,608	773,122
Common stock reserved under convertible senior notes	13,225,000
Total	29,706,899	12,480,275
Maximum
Common Stock
Conversion ratio	50

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Common Stock

6 Months Ended

Jun. 30, 2026

Common Stock

Common Stock

10.Common Stock

In September 2024, upon the completion of the IPO, the Company restated its certificate of incorporation, pursuant to which the Company is authorized to issue 175,000,000 shares of common stock $0.0001 par value. The voting, dividend and liquidation rights of the holders of the Company’s common stock were subject to and qualified by the rights, powers and preference of the holders of any preferred stock then issued and outstanding.

In October 2025, the Company entered into a sales agreement with Jefferies under which the Company could, from time to time, issue and sell shares of its common stock having aggregate sales proceeds of up to $200.0 million, in a series of one or more at-the-market equity offerings (“2025 ATM Program”). The Company’s common stock will be sold at prevailing market prices at the time of the sale; and as a result, prices may vary. For the three months ended June 30, 2026, the Company did not sell any shares of common stock under the 2025 ATM Program. As of June 30, 2026, $96.8 million remained available under the 2025 ATM Program.

In October 2025, the Company entered into a securities purchase agreement for a private placement in public entity (“PIPE”) (the “PIPE Purchase Agreement”), pursuant to which the Company sold (i) 6,262,112 shares of common stock to certain institutional and accredited investors at a price of $19.00 per share and (ii) 48,918 shares of common stock to certain directors and officers of the Company at a price of $20.85 per share. The net proceeds from the PIPE offering, after deducting placement agent fees and other offering costs were $111.8 million.

In March 2026, the Company completed a follow-on equity offering under which it issued and sold 5,000,000 shares of common stock at a public offering price of $20.00 per share. Total proceeds for the follow-on offering were approximately $100.0 million, before deducting commissions and estimated offering costs of $6.4 million payable by the Company.

In April 2026, the underwriters of the Company’s follow-on equity offering exercised their overallotment option in full, pursuant to which the Company issued and sold an additional 750,000 shares of common stock, at $20.00 per share, for gross proceeds of $15.0 million, before deducting commissions and estimated offering costs of $0.9 million payable by the Company.

The holders of the common stock are entitled to one vote for each share of common stock held at all meetings of stockholders (and written actions in lieu of meetings), and there are no cumulative voting rights.

The Company has reserved the following shares of common stock for the potential conversion of outstanding stock options, restricted stock units (“RSUs”), employee stock purchase plan and conversion of Convertible Notes:


	June 30, 2026	December 31, 2025
Options to purchase common stock	12,645,400	10,675,615
Remaining shares reserved for future issuance	1,299,197	431,863
RSUs	1,263,694	599,675
Employee stock purchase plan	1,273,608	773,122
Common stock reserved under convertible senior notes¹	13,225,000	—
Total	29,706,899	12,480,275

¹Represents a maximum conversion rate of 50.0000 shares of common stock per $1,000 principal amount of notes.

- Definition

The entire disclosure for equity.

+ References

+ Details

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2026	Jul. 31, 2026
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2026
Document Transition Report	false
Entity File Number	001-42270
Entity Registrant Name	Zenas BioPharma, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	93-2749244
Entity Address, Address Line One	852 Winter Street
Entity Address, Adress Line Two	Suite 250
Entity Address, City or Town	Waltham
Entity Address State Or Province	MA
Entity Address, Postal Zip Code	02451
City Area Code	857
Local Phone Number	271-2954
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Title of 12(b) Security	Common stock, par value $0.0001 per share
Trading Symbol	ZBIO
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		65,176,723
Entity Central Index Key	0001953926
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2
Amendment Flag	false

Royalty Obligation (Details) - Royalty obligation - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Sep. 30, 2025	Jun. 30, 2026
Royalty Obligation
Proceeds from royalty obligation	$ 75,000	$ 75,000
Percentage of royalty on net sales	5.50%
Percentage of royalty on net sales by licensees	5.50%
Percentage of royalty on income earned from licensees	25.00%
Percentage of royalty on non-royalty income earned from licensees	25.00%
Additional payment	$ 225,000
Issuance costs	3,700	$ 3,691
Zenas' INDIGO Phase 3 Trial
Royalty Obligation
Additional payment	75,000
FDA approval for IgG4-Related Disease
Royalty Obligation
Additional payment	75,000
FDA for the treatment of systemic lupus erythematosus
Royalty Obligation
Additional payment	$ 75,000

Commitments and Contingencies

6 Months Ended

Jun. 30, 2026

Commitments and Contingencies

Commitments and Contingencies

13.Commitments and Contingencies

Other Contracts

The Company has entered into agreements with certain vendors for the provision of services that the Company is not contractually able to terminate for convenience and thereby avoid any and all future obligations to the vendors. Under such agreements, the Company is contractually obligated to make certain minimum payments to the vendors, with the exact amounts in the event of termination to be based on the timing of the termination and the exact terms of the agreement. As of June 30, 2026, our total non-cancellable clinical manufacturing contract payment obligations are $15.8 million of which the full obligation is payable within 12 months.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and certain officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or services as directors. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not currently aware of any indemnification claims and had not accrued any liabilities related to such obligations in its unaudited condensed consolidated financial statements as of June 30, 2026.

Litigation and Other Proceedings

The Company may periodically become subject to legal proceedings and claims arising in the ordinary course of business. As of June 30, 2026, the Company was not subject to any material legal proceedings which would reasonably be expected to have a material adverse effect on the Company’s financial results.

Common Stock (Details) $ / shares in Units, $ in Thousands	1 Months Ended			6 Months Ended
Common Stock (Details) $ / shares in Units, $ in Thousands	Apr. 30, 2026 USD ($) $ / shares shares	Mar. 31, 2026 USD ($) Vote $ / shares shares	Oct. 31, 2025 USD ($) $ / shares shares	Jun. 30, 2026 USD ($) $ / shares shares	Dec. 31, 2025 $ / shares shares	Sep. 30, 2024 $ / shares shares
Common Stock
Common stock, shares authorized (in shares) \| shares				175,000,000	175,000,000	175,000,000
Common stock, par value (in dollar per share) \| $ / shares				$ 0.0001	$ 0.0001	$ 0.0001
Maximum value of common stock to be issued			$ 200,000
Convertible preferred stock, number of votes per share \| Vote		1
Private Investment in Public Equity
Common Stock
Net proceeds			$ 111,800
ATM Program
Common Stock
Proceeds from Issuance of Common Stock				$ 71,532
Amount of capital stock				$ 96,800
Follow On Public Equity Offering
Common Stock
Number of common stock issued \| shares	750,000	5,000,000
Public offering price \| $ / shares	$ 20	$ 20
Proceeds from Issuance of Common Stock	$ 15,000	$ 100,000
Commissions and estimated offering costs	$ 900	$ 6,400
Investors \| Private Investment in Public Equity
Common Stock
Number of common stock issued \| shares			6,262,112
Public offering price \| $ / shares			$ 19
Directors and officers \| Private Investment in Public Equity
Common Stock
Number of common stock issued \| shares			48,918
Public offering price \| $ / shares			$ 20.85

Pay vs Performance Disclosure - USD ($) $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Feb. 28, 2026	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Pay vs Performance Disclosure
Net Income (Loss)	$ (111,500)	$ (111,456)	$ (80,987)	$ (52,223)	$ (33,573)	$ (192,443)	$ (85,796)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Long - Term Obligations - Senior Secured Term Loan - Carrying Value (Details) - Senior Secured Term Loan - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026
Debt Instrument [Line Items]
Outstanding principal balance	$ 75,000
Accumulated PIK interest applied to term loan balance	1,894
Unamortized debt discounts and issuance costs	(2,834)	$ (3,000)
Carrying value	$ 74,060

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References + Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Long - Term Obligations - Convertible debt - Carrying value (Details) - 2.50% convertible senior notes due 2032 $ in Thousands	Jun. 30, 2026 USD ($)
Royalty Obligation
Outstanding principal balance	$ 230,000
Unamortized debt discounts and issuance costs	(7,044)
Carrying value	$ 222,956

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References + Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

Related Party Transactions

6 Months Ended

Jun. 30, 2026

Related Party Transactions

Related Party Transactions

14.Related Party Transactions

Xencor, Inc.

The Company has obtained exclusive, worldwide licenses from Xencor to research, develop, manufacture, market and sell three antibody product candidates pursuant to two license agreements. The Company has concluded that Xencor is a related party, due to the issuance of convertible preferred stock in December 2020 and April 2023. In connection with the completion of the IPO, in September 2024, all outstanding shares of preferred stock converted into shares of common stock. As of June 30, 2026, Xencor held less than 10% of the shares of the Company’s outstanding common stock.

Viridian Therapeutics, Inc.

The Company has obtained a license from Viridian to research, develop, manufacture, market and sell an antibody product candidate in China. Prior to May 2026, the Company concluded that Viridian was a related party because although Fairmount Funds Management LLC owns less than 10% of shares of the Company’s outstanding common stock, they held a seat on the Board and are also a 10% or greater stockholder of Viridian and have two seats on Viridian’s board of directors. Effective May 2026, Fairmount Funds Management LLC no longer holds a seat on the Board and thus, the Company has determined that Viridian is no longer a related party.

Zai Lab (Hong Kong) Limited

The Company has granted a sublicense to Zai to develop, manufacture and commercialize ZB001 and related programs in greater China. The Company has concluded that Zai is a related party, as the Company’s CEO and Chairman is a member of Zai’s board of directors.

InnoCare Pharma Inc.

The Company has obtained the exclusive rights from InnoCare to develop, manufacture and commercialize three product candidates pursuant to the InnoCare License Agreement. Though InnoCare does not hold any direct controlling interest in the Company, the Company has concluded that InnoCare is a related party, due to the 5,000,000 shares of common stock issued and the 2,000,000 shares of common stock to be issued pursuant to the InnoCare License Agreement. As of June 30, 2026, InnoCare held less than 10% of the shares of the Company’s outstanding common stock.

For additional information on these arrangements, please see Note 7, License and Collaboration Revenue and Note 8, License Agreements, to these unaudited condensed consolidated financial statements.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

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+ Details

Common Stock (Tables)

6 Months Ended

Jun. 30, 2026

Common Stock

Schedule of common stock reserved for potential conversion and future issuance


	June 30, 2026	December 31, 2025
Options to purchase common stock	12,645,400	10,675,615
Remaining shares reserved for future issuance	1,299,197	431,863
RSUs	1,263,694	599,675
Employee stock purchase plan	1,273,608	773,122
Common stock reserved under convertible senior notes¹	13,225,000	—
Total	29,706,899	12,480,275

¹Represents a maximum conversion rate of 50.0000 shares of common stock per $1,000 principal amount of notes.

Long - Term Obligations

6 Months Ended

Jun. 30, 2026

Long - Term Obligations

Long - Term Obligations

6.Long – Term Obligations

Senior Secured Term Loan

In March 2026, the Company entered into the Loan Agreement with the Collateral Agent, BPCR Limited Partnership and BioPharma Credit Investments V (Master) LP, which are funds managed by Pharmakon and the guarantors party thereto. The Loan Agreement provides for a five-year senior secured term loan, which matures on March 27, 2031 (“Term Loan Maturity Date”), for up to $250.0 million and consists of five tranches (collectively, the “Term Loans”). Two of the tranches are committed tranches: (i) Tranche A in an aggregate of $75.0 million, which was funded on the date the Loan Agreement was executed; and (ii) Tranche B in an aggregate of $50.0 million (and up to an additional $25.0 million that the Company may elect to draw), which is available until November 1, 2027, subject to the occurrence of certain approval conditions (the “Tranche B/C Approval Condition”).

Three of the tranches may be drawn upon at the discretion of the Company: (i) Tranche C in an aggregate of $25.0 million (less any amounts elected to be (and actually) drawn under Tranche B in excess of $50.0 million), which is available until April 28, 2028; (ii) Tranche D in an aggregate of $50.0 million, which is available until October 30, 2028; and (iii) Tranche E in an aggregate of $50.0 million, which is available until April 30, 2029. Tranche C through E are subject to the occurrence of certain approval conditions and achievements of certain milestones in respect of certain net sales levels.

The Loan Agreement bears interest at annual interest rate of 3-month secured overnight financing rate (“SOFR”) subject to a 3.25% floor, plus 5.75% payable quarterly in arrears. The Company may elect for 100% of the interest for the first 24 months following the Tranche A Loan funding date to be paid-in-kind (“PIK Interest”) without an increase in the interest rate.

The Company is required to pay a funding fee equal to (i) 2.00% of the funding amount of the Tranche A on the funding date of such loan, (ii) 2.00% of $50,000,000 of the funding amount of the Tranche B on the funding date for such loan, (iii) 1.00% of any amounts in excess of $50,000,000 of the funding amount for the Tranche B on the funding date for such loan, and (iv) 1.00% of each of the funding amount of the Tranche C, Tranche D, and Tranche E on each respective funding date.

The Company paid the funding fee of $1.5 million for Tranche A as of March 31, 2026.

The Company’s obligations under the Loan Agreement are secured by substantially all of its assets, including its intellectual property, and are guaranteed by certain of its subsidiaries, each of which has pledged substantially all of their assets, including intellectual property, to secure such guarantee. The Company is also obligated to maintain a liquidity of not less than $50.0 million, immediately following the Tranche A closing date and until the satisfaction of the Tranche B/C Approval Condition.

The Company determined that all of the embedded features identified in the Loan Agreement were either clearly or closely related to the debt host and did not require bifurcation as a derivative liability, or the fair value of the bifurcated features was immaterial to the Company’s condensed consolidated financial statements.

Total net proceeds were $72.0 million after deducting discounts and debt issuance costs as of June 30, 2026. As of June 30, 2026, the Company elected to pay interest on the Term Loan as PIK Interest, which was added to the outstanding principal balance of the term loan. No repayment of principal was made during the three and six months ended June 30, 2026.

The following table reflects the Company’s senior secured term loan as of June 30, 2026 (in thousands):


	June 30,
	2026
Outstanding principal balance	$	75,000
Accumulated PIK interest applied to term loan balance		1,894
Unamortized debt discounts and issuance costs		(2,834)
Carrying value	$	74,060

The carrying value of the outstanding liability, which bears a variable interest rate indexed to the 3-month SOFR, approximates fair value as it reprices when market interest rates change and represents a Level 2 measurement within the fair value hierarchy.

The Company incurred $3.0 million of debt discounts and issuance costs, which were capitalized and deferred when incurred and subsequently amortized over the term of the Loan Agreement. The effective interest rate of the Loan Agreement, including the amortization of the debt issuance costs was 10.99% for the three months ended June 30, 2026.

Interest expense in relation to the Loan Agreement, including amortization of debt discounts and issuance costs amortization is as follows (in thousands):


	For the three months ended June 30,		For the six months ended June 30,
	2026		2026
Amortization of debt discounts and issuance costs	$	160	$	194
PIK interest expense (applied to term loan principal balance)		1,560		1,894
Total interest expense	$	1,720	$	2,088

Pursuant to the Loan Agreement, each tranche may be voluntarily prepaid at any time, in whole or subject to certain conditions, in part, prior to the Term Loan Maturity Date. Prepayments are subject to an amount equal to the sum of all interest that would have been accrued and payable from such date of prepayment through the second year anniversary of each respective tranche’s closing date on the amount of principal prepaid, using an interest rate in effect on such date.

Pursuant to the Loan Agreement, each tranche has a required prepayment premium, in an amount equal to the product of the amount of any prepaid principal, multiplied by: (i) if prepayment occurs prior to the third year anniversary of each respective tranche’s closing date, 3%; (ii) if prepayment occurs on or after the third year anniversary of each respective tranche's closing date but prior to the fourth year anniversary of each respective tranche's closing date, 2%; and (iii) if prepayment occurs on or after the four year anniversary of each respective tranche’s closing date but prior to the Term Loan Maturity Date, 1%.

Pursuant to the Loan Agreement, each tranche has a required exit consideration fee, with respect to any prepayment, repayment or as a result of the acceleration of maturity, an amount equal to the product of the amount of principal prepaid or repaid, multiplied by 1% to 2% based on the specific tranche. The Loan Agreement requires repayment in full of all

term loans in four equal payments commencing on September 30, 2028 to the extent the Tranche B/C Approval Condition is not met on or prior to June 30, 2028.

The Loan Agreement contains customary prepayment fees and provisions, events of default, including a material adverse change to the Company, and representations, warranties and covenants, including financial covenants. The financial covenants include (i) at all times prior to the satisfaction of the Tranche B/C Approval Condition, a minimum liquidity requirement and (ii) subject to the outstanding aggregate principal amount of Term Loans advanced under the Loan Agreement being equal to or greater than $200.0 million, a minimum trailing twelve months consolidated net revenue covenant.

As of June 30, 2026, the Company was in compliance with its debt covenants under the Loan Agreement.

Convertible Senior Notes

In March 2026, the Company issued an aggregate principal amount of $200.0 million of 2.50% convertible senior notes due 2032 (the “Convertible Notes”) with multiple individual investors (the “Holders”) in an underwritten public offering. In April 2026, the underwriters of the Company’s offering of the Convertible Notes exercised their overallotment option in full, pursuant to which the Company issued an additional principal amount of $30.0 million of Convertible Notes, before deducting commissions costs of $0.9 million. The Convertible Notes were issued pursuant to, and are governed by, an indenture (the “Base Indenture”), dated March 31, 2026, between the Company and U.S. Bank Trust Company, National Association, as trustee (the “Trustee”), as supplemented by a first supplemental indenture (the “Supplemental Indenture,” and the Base Indenture, as supplemented by the Supplemental Indenture, the “Indenture”), dated as of March 31, 2026, between the Company and the Trustee.

The Convertible Notes are general, unsecured, senior obligations of the Company. The Convertible Notes bear interest at 2.50% per annum, to be paid semi-annually in arrears on April 1 and October 1 of each year, beginning October 1, 2026. In addition, special interest will accrue on the notes upon the occurrence of certain events relating to the Company’s failure to file certain reports with the SEC as provided in the Indenture. The Convertible Notes mature on April 1, 2032 (the “Convertible Notes Maturity Date”), unless earlier converted, redeemed or repurchased by the Company.

The Holders may convert their notes into shares of common stock, at their option only in the following circumstances: (i) during any calendar quarter commencing after the calendar quarter ending on June 30, 2026; if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price for each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding quarter; (ii) during the five consecutive business days immediately after any 10 consecutive trading day period (the “Measurement Period”) in which the trading price per $1,000 principal amount of notes for each trading day of the Measurement Period was less than 98% of the product of the last reported sales price per share of the common stock on such trading day and the conversion rate on such trading day; (iii) upon the occurrence of certain corporate events or distributions of the Company’s common stock; (iv) if the Company calls such notes for redemption; and (v) at any time from, and including January 1, 2032 until the close of business on the scheduled trading day immediately before the Convertible Notes Maturity Date.

The Convertible Notes are redeemable, in whole or in part, subject to certain limitations, at the Company’s option any time and from time to time, on or after April 8, 2030 and on or before the twenty-sixth scheduled trading day immediately before the Convertible Notes Maturity Date, at a cash redemption price equal to the principal amount of Convertible Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date only if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date the Company sends the related redemption notice; and (ii) the trading day immediately before the date the Company sends such notice. However, the Company may not redeem less than all of the outstanding Convertible Notes unless at least $75.0 million aggregate principal amount of the Convertible Notes are outstanding and not called for redemption. In addition, calling any note for redemption will constitute a Make-Whole Fundamental Change, in which case the conversion rate applicable to the conversion of the note will be increased in certain circumstances if it is converted after it is called for redemption.

The initial conversion rate is 37.7358 shares of common stock per $1,000 principal amount of notes, which represents an initial conversion price of approximately $26.50 per share, and is subject to adjustment as described in the indenture. However, if a fundamental change occurs, generally a change of control, merger, consolidation, asset sale or similar transaction, takes place prior to April 1, 2030, and it results in the Convertible Notes immediately being due, the noteholders may be entitled to an increase in the conversion rate (“Make-Whole Rate”). The amount of the increase is determined pursuant to the contractual make-whole table based on the effective date of the transaction. No increase in the conversion rate will be provided if the stock price used to determine the adjustment is greater than $160.00 per share or less than $20.00 per share of common stock and the conversion rate as increased to the Make-Whole provision will not exceed 50.00 shares of common stock per $1,000 principal amount of the Convertible Notes.

The Company will settle conversions by paying or delivering cash, shares of its common stock or a combination of cash and shares of its common stock, at the Company’s election. If the Company elects to deliver cash or a combination of cash and shares of its common stock, then the consideration due upon conversion will be determined over a period consisting of 25 volume-weighted average price (“VWAP”) trading days.

The Convertible Notes were accounted for in accordance with ASC Subtopic 470-20, Debt with Conversion and Other Options (“ASC 470-20”) and ASC Subtopic 815-40, Contracts in Entity’s Own Equity (“ASC 815-40”). Under ASC 81-40, to qualify for equity classification (or non-bifurcation, if embedded), the instrument (or embedded feature) must be both (i) indexed to the issuer’s stock and (ii) meet the requirements of the equity classification guidance. Based upon our analysis, it was determined that the Convertible Notes do contain embedded features indexed to our common stock, but do not meet the requirements for bifurcation, and therefore do not need to be separately accounted for as an equity component. Since the embedded conversion feature meets the equity scope exception from derivative accounting, and, also since the embedded conversion option does not need to be separately accounted for as an equity component under ASC 470-20, the proceeds from the issuance of the Convertible Notes were recorded as a liability.

The Company incurred issuance costs related to the Convertible Notes of $7.3 million, which were recorded as debt issuance costs and were included as a reduction to the Convertible Notes on the unaudited condensed consolidated balance sheet. The debt issuance costs are amortized to interest expense using the effective interest rate method over the term of the Convertible Notes, resulting in an effective interest rate of 3.07%.

The outstanding balance of the Convertible Notes consisted of the following as of June 30, 2026 (in thousands):


	June 30,
	2026
Outstanding principal balance	$	230,000
Unamortized commissions and offering costs		(7,044)
Carrying value	$	222,956

The fair value of the Convertible Notes is influenced by the Company’s common stock price and has been classified as Level 1 within the fair value hierarchy as it uses quoted prices in active markets. The estimated fair value of the Convertible Notes as of June 30, 2026, was approximately $275.5 million.

None of the Convertible Notes were converted, nor did the Company redeem any of the Convertible Notes as of June 30, 2026.

Interest expense in relation to the Convertible Notes, including amortization of commissions and offering costs is as follows (in thousands):


	For the three and six months ended June 30,
	2026
Cash interest expense	$	1,465
Amortization of commissions and offering costs		280
Total interest expense	$	1,745

The indenture contains customary events of default and covenants, including (i) certain payment defaults on the notes (ii) a default by the Company in its other obligations or agreements under the Indenture or the Notes if such default is not cured or waived within 60 days after notice is given in accordance with the Indenture; (iii) certain defaults by the Company or any of its significant subsidiaries with respect to indebtedness for borrowed money of at least $30,000,000; (iv) certain final judgments being rendered against the Company or any of its significant subsidiaries for the payment of at least $30,000,000, where such judgments are not discharged or stayed within 60 days after the date on which the right to appeal has expired or on which all rights to appeal have been extinguished; and (v) certain events of bankruptcy, insolvency and reorganization involving the Company or any of its significant subsidiaries.

As of June 30, 2026, the Company was in compliance with its covenants under the Indenture.

Stock-Based Compensation (Details) - USD ($) $ in Millions			1 Months Ended	3 Months Ended	6 Months Ended
Stock-Based Compensation (Details) - USD ($) $ in Millions	Jan. 01, 2026	Sep. 03, 2024	Sep. 30, 2024	Jun. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Dec. 10, 2025
Stock-Based Compensation
Options to purchase common stock				12,645,400	12,645,400	10,675,615
Granted (in shares)					2,299,700
Number of shares of common stock available for future grant				29,706,899	29,706,899	12,480,275
Restricted stock units
Stock-Based Compensation
Vesting period (years)					4 years
RSUs vested during the period, fair value				$ 2.2	$ 2.2
2020 Plan
Stock-Based Compensation
Options to purchase common stock				3,092,255	3,092,255
2024 Plan
Stock-Based Compensation
Maximum additional number of outstanding capital stock percent		5.00%
Increase in common stock available for issuance	3,156,138
Number of shares of common stock available for future grant				1,028,297	1,028,297
Employment inducement grants
Stock-Based Compensation
Granted (in shares)					1,062,000
2024 ESPP
Stock-Based Compensation
Maximum additional number of outstanding capital stock percent		1.00%
Increase in common stock available for issuance	1,317,977
Number of shares of common stock available for future grant				1,273,608	1,273,608
Additional shares To Be authorized			1,000,000
Shares issued under ESPP				0	44,369
2026 Inducement Plan
Stock-Based Compensation
Number of shares of common stock available for future grant				270,900	270,900		1,000,000

Stock-Based Compensation - Restricted Stock Units (Details)	6 Months Ended
	Jun. 30, 2026 $ / shares shares
Number of Shares
Unvested as of beginning (in shares)	599,675
Unvested as of ending (in shares)	1,263,694
Restricted stock units
Number of Shares
Unvested as of beginning (in shares)	599,675
Granted (in shares)	848,100
Vested (in shares)	(119,545)
Forfeited (in shares)	(64,536)
Unvested as of ending (in shares)	1,263,694
Weighted-Average Grant-Date Fair Value
Unvested as of beginning (in dollars per share) \| $ / shares	$ 14.23
Granted (in dollars per share) \| $ / shares	19.49
Vested (in dollars per share) \| $ / shares	11.94
Forfeited (in dollars per share) \| $ / shares	12.81
Unvested as of ending (in dollars per share) \| $ / shares	$ 18.05

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Stock-Based Compensation Expense
Total stock-based compensation expense	$ 8,619	$ 6,045	$ 17,814	$ 11,431
Research and development
Stock-Based Compensation Expense
Total stock-based compensation expense	3,861	2,113	6,957	3,694
General and administrative
Stock-Based Compensation Expense
Total stock-based compensation expense	$ 4,758	$ 3,932	$ 10,857	$ 7,737

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 196,577	$ 110,641
Short-term investments	446,549	232,551
Prepaid expenses and other current assets	10,668	7,979
Total current assets	653,794	351,171
Property and equipment, net	23	34
Operating lease right-of-use assets, net	821	1,354
Long-term investments	30,763	17,272
Other non-current assets	16,289	13,809
Total assets	701,690	383,640
Current liabilities:
Accounts payable	7,589	7,111
Accrued expenses	57,406	54,423
Operating lease liabilities, current	823	1,115
Total current liabilities	65,818	62,649
Long-term liabilities:
Royalty obligation	91,737	78,636
Senior secured term loan, net	74,060
Convertible senior notes, net	222,956
Operating lease liabilities, less current portion	22	211
Total long-term liabilities	388,775	78,847
Total liabilities	454,593	141,496
Stockholders' equity:
Common stock, par value $0.0001 per share; 175,000,000 shares authorized at June 30, 2026 and December 31, 2025, respectively; 63,330,747 and 54,485,518 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively	6	5
Additional paid-in capital	1,205,803	1,007,331
Accumulated other comprehensive loss	(1,141)	(64)
Accumulated deficit	(957,571)	(765,128)
Total stockholders' equity	247,097	242,144
Total liabilities and stockholders' equity	$ 701,690	$ 383,640

Related Party Transactions (Details)	4 Months Ended	6 Months Ended
Related Party Transactions (Details)	May 10, 2026 item	Jun. 30, 2026 item shares
Xencor \| Related party
Related Party Transactions
Number of antibody product candidates		3
Number of license agreements		2
Xencor \| Related party \| Maximum
Related Party Transactions
Ownership percentage by related party		10.00%
Viridian
Related Party Transactions
Ownership percentage by related party	10.00%
Viridian \| Fairmount Funds Management LLC
Related Party Transactions
Number of seats held in board	2
Viridian \| Fairmount Funds Management LLC \| Maximum
Related Party Transactions
Ownership percentage by related party	10.00%
InnoCare \| Related party
Related Party Transactions
Number of common stock issued \| shares		5,000,000
Number of products		3
Number of shares issued \| shares		2,000,000
InnoCare \| Related party \| Maximum
Related Party Transactions
Ownership percentage by related party		10.00%

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenue:
License and collaboration revenue	$ 1,000		$ 1,000	$ 10,000
Total revenue	1,000		1,000	10,000
Operating expenses:
Research and development	62,913	$ 43,027	123,352	77,942
General and administrative	15,746	12,136	32,657	24,551
Acquired in-process research and development	30,000		30,000
Total operating expenses	108,659	55,163	186,009	102,493
Loss from operations	(107,659)	(55,163)	(185,009)	(92,493)
Other income (expense), net:
Interest expense on royalty obligation	(6,837)		(13,100)
Interest expense on senior secured term loan	(1,720)		(2,088)
Interest expense on convertible senior notes	(1,745)		(1,745)
Interest income	6,603	2,743	9,621	6,136
Other income (expense), net	16	217	(8)	376
Total other income (expense), net	(3,683)	2,960	(7,320)	6,512
Loss before income taxes	(111,342)	(52,203)	(192,329)	(85,981)
Income tax provision (benefit)	114	20	114	(185)
Net loss	$ (111,456)	$ (52,223)	$ (192,443)	$ (85,796)
Net loss per share - basic (in dollars per share)	$ (1.77)	$ (1.25)	$ (3.24)	$ (2.05)
Net loss per share - diluted (in dollars per share)	$ (1.77)	$ (1.25)	$ (3.24)	$ (2.05)
Weighted-average common stock outstanding - basic (in shares)	63,112,314	41,865,400	59,393,300	41,833,279
Weighted-average common stock outstanding - diluted (in shares)	63,112,314	41,865,400	59,393,300	41,833,279
Comprehensive loss:
Net loss	$ (111,456)	$ (52,223)	$ (192,443)	$ (85,796)
Other comprehensive income (loss):
Unrealized (loss) gain on investments	(780)	30	(1,121)	42
Foreign currency translation adjustment	16	(265)	44	(330)
Comprehensive loss	$ (112,220)	$ (52,458)	$ (193,520)	$ (86,084)

Royalty Obligation

6 Months Ended

Jun. 30, 2026

Royalty Obligation

Royalty Obligation

9.Royalty Obligation

In September 2025, the Company and Royalty Pharma entered into the Royalty Purchase Agreement. Pursuant to the Royalty Purchase Agreement, the Company received a $75.0 million upfront payment in exchange for which Royalty Pharma purchased the right to receive, for each calendar quarter, (i) 5.5% of net sales of obexelimab products sold by the Company and its affiliates worldwide, (ii) 5.5% of net sales of obexelimab products sold by licensees of Zenas and its affiliates in the U.S., the United Kingdom and the European Union, (iii) 25% of royalty income payable to Zenas or any of its affiliates on sales of obexelimab products in countries other than the U.S., the United Kingdom, and in the European Union by its licensees pursuant to out-licenses less royalty payments payable by Zenas to Xencor Inc. and (iv) 25% of non-royalty income attributable to obexelimab products payable to Zenas or any of its affiliates by its licensees (other than certain milestone payments payable by Bristol-Myers Squibb) pursuant to out-licenses and allocated to countries other than the U.S., the United Kingdom and in the European Union.

The Royalty Purchase Agreement provides for an additional $225.0 million of payments to be paid to the Company by Royalty Pharma upon the occurrence of certain triggering events which includes (1) $75.0 million payable upon the achievement of certain milestones with respect to Zenas’ INDIGO Phase 3 Trial, noting the Company is not currently eligible for this milestone, (2) $75.0 million payable following receipt of marketing approval for obexelimab from the U.S. Food and Drug Administration (the “FDA”) for the treatment of IgG4-Related Disease on or before a specified date and (3) $75.0 million payable following receipt of marketing approval for obexelimab from the FDA for the treatment of systemic lupus erythematosus on or before a specified date.

The Company accounted for the Royalty Purchase Agreement as a debt financing, primarily because it has significant continuing involvement in generating the future revenue on which the royalty payments are based. The $75.0 million upfront payment received was recorded as a liability, net of issuance costs of $3.7 million. The effective interest rate was determined based on the Company’s projections of future payments to Royalty Pharma. The Company will evaluate the estimated timing and amount of future royalty payments for each reporting period and will revise the effective interest rate prospectively if those estimates change materially.

The following table shows the activity within the liability account of the arrangement (in thousands):



	Period from inception to June 30, 2026
Proceeds from royalty obligation	$	75,000
Issuance costs		(3,691)
Interest expense related to royalty obligation		20,428
Royalty obligation as of June 30, 2026	$	91,737
Effective interest rate		32.3%

The fair value of the liability approximates the carrying value and was determined based on the current estimate of the timing and amount of expected future royalty payments expected to be paid over the estimated term of the Royalty Purchase Agreement, which are subject to significant estimation uncertainty and are based on various assumptions made by the Company. These assumption inputs are determined to be Level 3 inputs in the fair value hierarchy as they involve significant unobservable inputs and judgment.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
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-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
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-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/470/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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+ Details

License and Collaboration Revenue

6 Months Ended

Jun. 30, 2026

License and Collaboration Revenue

License and Collaboration Revenue

7.License and Collaboration Revenue

License and Collaboration Agreement with Bristol-Myers Squibb

In August 2023, the Company entered into a license and collaboration agreement (the “BMS Agreement”) with Bristol-Myers Squibb (“BMS”), under which the Company granted BMS an exclusive license to (i) develop, manufacture (subject to the Company’s rights to be the exclusive manufacturer for BMS for a certain period of time), commercialize or otherwise exploit obexelimab and any biological product (irrespective of presentations, formulations or dosages) containing obexelimab but not any of the Company’s other proprietary active ingredient (the “BMS Product”) into Japan, South Korea, Taiwan, Singapore, Hong Kong and Australia (collectively, the “BMS Territory”) and (ii) develop and manufacture obexelimab and the BMS Product outside the BMS Territory provided that obexelimab and the BMS Product are solely used in the BMS Territory.

Pursuant to the BMS Agreement, BMS paid the Company a one-time non-refundable upfront cash payment of $50.0 million. The Company is entitled to receive further separate development, regulatory milestone payments from BMS of up to approximately $79.5 million. The Company is also entitled to receive one-time sales milestone payments up to $70.0 million upon BMS achieving certain net sales milestones in a given year in the BMS Territory. The Company is also eligible to receive tiered high single-digit to low double-digit royalties on net sales in the BMS Territory, subject to specified reductions.

The Company will continue to perform and oversee the ongoing Phase 3 trial of obexelimab in the immunoglobulin G4-related disease (“IgG4-RD”) indication and BMS will participate in the performance of the study. BMS will fund their pro rata share of the total global study costs up to a specified percentage of the patients enrolled in the study from the BMS Territory. The global development activities under the agreement do not represent a transaction with a customer and reimbursement payments received by the Company for global development activities are accounted for as a reduction of the related research and development expenses.

As of June 30, 2026 and 2025, the Company recorded $0.8 million and $1.3 million, respectively, as a receivable included in prepaid expenses and other current assets. The Company recorded $0.8 million and $1.3 million for the three months ended June 30, 2026 and 2025, respectively, and $1.9 million and $3.0 million for the six months ended June 30, 2026 and 2025, respectively, as a reduction to research and development expense for global development costs to be reimbursed by BMS. The Company did not recognize revenue related to the BMS Agreement during the three and six months ended June 30, 2026 and 2025.

Tenacia Biotechnology Co. Novation Agreement

In October 2024, the Company entered into a novation agreement with Tenacia Biotechnology (Hong Kong) Co., Limited (“Tenacia”), under which the Company transferred its rights and obligations under the agreements with Dianthus to Tenacia (the “Tenacia Agreement”). Pursuant to the Tenacia Agreement, Tenacia paid the Company a one-time non-refundable upfront cash payment of $5.0 million, which was recognized as revenue in the fourth quarter of 2024.

During the three and six months ended June 30, 2026, the Company recognized revenue of $1.0 million, related to the achievement of a certain development milestone. The Company did not recognize revenue related to the Tenacia Agreement during the three and six months ended June 30, 2025. The Company is entitled to receive remaining development, regulatory, and sales milestones from Tenacia of up to approximately $85.0 million if certain milestones are achieved.

License Agreement with Zai Lab (Hong Kong) Limited

In January 2025, the Company entered into a license agreement (the “Zai License Agreement”), with Zai, under which the Company granted Zai an exclusive sublicense to develop, manufacture and commercialize ZB001 and related programs in greater China. Under the Zai License Agreement, Zai will be responsible for conducting all research and development activities, manufacturing, regulatory and commercialization in greater China.

Pursuant to the Zai License Agreement, Zai paid the Company a one-time non-refundable upfront cash payment of $10.0 million. The Company is entitled to receive further development, regulatory and sales milestones from Zai up to approximately $117.0 million if certain milestones are successfully achieved, with passthrough obligations of $21.0 million due to Viridian Therapeutics, Inc. (“Viridian”). The Company is also eligible to receive tiered royalties on net sales in greater China, ranging from the low to mid-single digits, net of passthrough obligations due to Viridian.

The Company evaluated the terms of the Zai License Agreement and determined it is within the scope of ASC 606. The Company identified the following promises in the Zai License Agreement that were evaluated under the scope of ASC 606: (i) transfer of the license for ZB001, (ii) licensed technology transfer (iii) licensed material transfer and (iv) continued licensed technology transfer. The Company also evaluated whether certain options outlined in the Zai License Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options conveyed a material right to Zai or were immaterial and, therefore, are not considered separate performance obligations within the Zai License Agreement.

The Company assessed the above promises and determined that the license for ZB001 and technology transfer are a combined distinct performance obligation within the scope of ASC 606. The licensed material transfer and the continued technology know-how transfer services are promises that are separately identifiable and considered to be distinct. The Company determined the transfer of the licensed materials and continued technology know-how transfer services were immaterial in the context of the contract based on the minimal resources required to fulfill the obligations and the estimated standalone selling price of the licensed materials. Therefore, the sublicense and technology transfer represent a single performance obligation at contract inception.

The Company concluded that the transaction price of $10.0 million was allocated to the combined performance obligation, which was recognized upon delivery prior to March 31, 2025. The Company used the most likely amount method to estimate variable consideration and estimated that the most likely amount for each potential developmental and regulatory variable consideration milestone payment under the agreement is zero, as achievement of those milestones is uncertain and susceptible to factors outside the Company’s control. Accordingly, all such milestone payments were excluded from the transaction price. Management will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, will adjust the transaction price as necessary. Sales and royalty based milestones structured on the level of sales, were also excluded from the transaction price, as the license is deemed to be the predominant item to which the transaction price relates. The Company will recognize such milestone and royalty revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied).

As of June 30, 2026 and 2025, no milestones were achieved or deemed probable of achievement.

Subsequent Events

6 Months Ended

Jun. 30, 2026

Subsequent Events

Subsequent Events

16.Subsequent Events

ATM Program

In July 2026, the Company completed the sale of 1,818,181 shares of common stock under the 2025 ATM Program, with an average gross sales price of $27.50 per share, resulting in proceeds of $48.7 million, net of commissions. As of the issuance date of these financial statements, $46.8 million remained available under the 2025 ATM Program.

Achievement of specified regulatory milestone pursuant to the BMS Agreement

In August 2026, BMS announced the achievement of a specified regulatory milestone under the BMS Agreement, which requires BMS to make a milestone payment of $10.0 million to the Company. Due to the achievement of the specified regulatory milestone by BMS, the Company is obligated to make a milestone payment of $2.5 million to Xencor pursuant to the 2021 Xencor Agreement.

Amendment to 2026 Inducement Plan

In August 2026, the 2026 Inducement Plan was amended to increase the number of equity awards available for grant by 600,000.

Achievement of Near-term Milestone pursuant to the InnoCare Agreement

In August 2026, the Company achieved the Near-term Milestone and is obligated to make a milestone payment of $25.0 million and issue 2,000,000 shares of common stock to InnoCare.

Fair Value Measurements - Available-for-sale securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value Measurements
Amortized Cost	$ 478,246	$ 249,636
Gross Unrealized Gains	3	192
Gross Unrealized Losses	(937)	(5)
Fair Value	477,312	249,823
Commercial paper
Fair Value Measurements
Amortized Cost	24,236	5,957
Gross Unrealized Gains		2
Gross Unrealized Losses	(19)
Fair Value	24,217	5,959
Corporate debt securities
Fair Value Measurements
Amortized Cost	95,670	45,740
Gross Unrealized Gains	2	28
Gross Unrealized Losses	(122)	(2)
Fair Value	95,550	45,766
Government securities
Fair Value Measurements
Amortized Cost	358,340	197,939
Gross Unrealized Gains	1	162
Gross Unrealized Losses	(796)	(3)
Fair Value	$ 357,545	$ 198,098

Segment Information (Tables)

6 Months Ended

Jun. 30, 2026

Segment Information

Schedule of financial data for reportable segments

The following table presents certain financial data for the Company’s reportable segment for the three and six months ended June 30, 2026 and 2025 (in thousands):


		For the three months ended June 30,				For the six months ended June 30,
		2026		2025		2026		2025
Revenue	$	1,000	$	—	$	1,000	$	10,000
Less:
Direct research and development expenses:¹
Obexelimab		29,394		29,894		61,154		53,254
Orelabrutinib		11,206		—		21,307		—
Other programs (ZB002, ZB004, ZB014, ZB021 & ZB022)		1,458		400		2,026		736
Partnered regional programs (ZB001 & ZB005)		(24)		(137)		(24)		(37)
Unallocated research and development²		17,018		10,757		31,932		20,295
General and administrative³		10,988		8,204		21,800		16,814
Acquired in-process research and development⁴		30,000		—		30,000		—
Stock-based compensation		8,619		6,045		17,814		11,431
Other segment items⁴		3,797		(2,940)		7,434		(6,697)
Segment net loss	$	(111,456)	$	(52,223)	$	(192,443)	$	(85,796)

¹Direct research and development expenses primarily consist of direct costs incurred to specific program research and development activities, including costs to conduct clinical trials and to manufacture clinical drug supply.

² Unallocated research and development expenses primarily consist of indirect costs incurred in support of overall research and development activities and non-specific programs, including activities that benefit multiple programs, such as personnel costs for employees involved in research and development activities, excluding stock-based compensation, as well as contract services not allocated to specific programs.

³General and administrative expenses primarily consist of professional fees, depreciation expense, facilities expenses as well as all other personnel costs, excluding stock-based compensation.

⁴Acquired -in- process research and development expenses consist of milestones achieved pursuant to the Xencor and InnoCare license agreements, for additional details see Note 8, License Agreements to these condensed consolidated financial statements.

⁵ Other segment items consist of other (income) expense, net, and income tax (benefit) provision. Other (income) expense, net consists of interest income, interest expense related to the royalty obligation, the senior secured term loan and convertible senior note as well as realized and unrealized gains and losses on foreign currency transactions.

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Jul. 31, 2026	Aug. 31, 2026	Oct. 31, 2025
Subsequent Events
Maximum value of common stock to be issued			$ 200.0
InnoCare Pharma Inc
Subsequent Events
Regulatory milestones payable			$ 20.0
Subsequent event \| 2026 Inducement Plan
Subsequent Events
Increase in common stock available for issuance		600,000
Subsequent event \| InnoCare Pharma Inc
Subsequent Events
Milestone payment payable		$ 25.0
Number of shares to be issued due to achievement of specified events		2,000,000
Subsequent event \| BMS Agreement
Subsequent Events
Milestone payment receivable	$ 10.0
Subsequent event \| 2021 Xencor Agreement
Subsequent Events
Regulatory milestones payable	$ 2.5
Subsequent event \| ATM Program
Subsequent Events
Number of common stock issued	1,818,181
Public offering price	$ 27.5
Net proceeds	$ 48.7
Maximum value of common stock to be issued	$ 46.8

Accrued Expenses

6 Months Ended

Jun. 30, 2026

Accrued Expenses

Accrued Expenses

5.Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	June 30, 2026			December 31, 2025
External research, development and manufacturing expenses	$	43,632		$	38,855
Employee compensation and benefits		9,836			13,080
Professional and consultant fees		1,702			1,500
Interest expense on convertible senior notes		1,465			—
Income taxes payable		—			118
Other		771			870
Total accrued expenses	$	57,406		$	54,423

Nature of Business

6 Months Ended

Jun. 30, 2026

Nature of Business

Nature of Business

1.Nature of Business

Organization

Zenas BioPharma, Inc. (“Zenas” or the “Company”) was incorporated in November 2019 as Zenas BioPharma (Cayman) Limited, an exempted company incorporated in the Cayman Islands with limited liability and commenced operations in 2020. On August 2, 2023, the Company (then known as Zenas BioPharma (Cayman) Limited) de-registered from the Cayman Islands and registered by way of continuation in the State of Delaware. Zenas is a clinical-stage global biopharmaceutical company committed to being a leader in the development and commercialization of transformative immunology-based therapies for patients in need. The Company’s goal is to build an immunology and inflammation (“I&I”) focused biopharmaceutical company. The Company has in-licensed and is developing several product candidates for the treatment of various auto-immune and rare diseases. The Company is headquartered in Waltham, Massachusetts and operates in one segment, which is the business of acquiring and developing immune-based therapies for potential commercialization.

The Company’s condensed consolidated financial statements include the accounts of its wholly owned subsidiaries which include Zenas BioPharma (HK) Limited (“Zenas HK”), Zenas BioPharma (USA) LLC, Shanghai Zenas Biotechnology Co. Limited, Zenas BioPharma Securities Corp., Zenas BioPharma GmbH (Switzerland), Zenas BioPharma B.V. and Zenas BioPharma GmbH (Germany).

Liquidity and Capital Resources

Since its inception, the Company has devoted its efforts principally to research and development and raising capital. The Company is subject to risks and uncertainties common to clinical stage companies in the biopharmaceutical industry, including, but not limited to, completing preclinical studies and clinical trials, obtaining regulatory approval for product candidates, market acceptance of products, development by competitors of new technological innovations, dependence on key personnel, the ability to attract and retain qualified employees, reliance on third-party organizations, protection of proprietary technology, compliance with government regulations, and the ability to raise additional capital to fund operations.

The Company’s capital to date has been generated primarily with proceeds received through the sale and issuance of preferred stock, convertible senior notes, the sale of common stock from its initial public offering (“IPO”), private and public equity offerings (please see Note 10, Common Stock, to these unaudited condensed consolidated financial statements), as well as from payments received under the Company’s license, collaboration and royalty purchase agreements (please see Note 7, License and Collaboration Revenue and Note 9, Royalty Obligation, to these unaudited condensed consolidated financial statements) and the senior secured term loan with Pharmakon Advisors, LP (“Pharmakon”) (please see Note 6, Long-Term Obligations, to these unaudited condensed consolidated financial statements).

The Company has not generated any revenue from product sales since inception, and its product candidates currently under development will require significant additional research and development efforts and regulatory approval prior to commercialization.

The Company has incurred operating losses and negative cash flows since its inception, including net losses of $111.5 million and $52.2 million for the three months ended June 30, 2026 and 2025, respectively, and $192.4 million and $85.8 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, the Company had an accumulated deficit of $957.6 million. Management expects operating losses and negative operating cash flows to continue for the foreseeable future.

The Company expects that its existing cash, cash equivalents and investments of $673.9 million as of June 30, 2026, will be sufficient to fund its operating and capital expenditures for at least twelve months from the date of the issuance of these unaudited condensed consolidated financial statements.

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Cash flows from operating activities:
Net loss	$ (192,443)	$ (85,796)
Adjustments to reconcile net loss to net cash used in operating activities:
Acquired in-process research and development	30,000
Depreciation expense	10	35
Loss on disposal of property and equipment		107
Net amortization of premiums and accretion of discounts on investments	(1,397)	(1,317)
Non-cash interest expense on royalty obligation	13,100
Non-cash interest expense on senior secured term loan	2,088
Non-cash interest expense on convertible senior notes	280
Stock-based compensation expense	17,814	11,431
Non-cash lease expense	533	446
Prepaid expenses and other assets	(5,373)	802
Accounts payable	461	(9,205)
Accrued expenses	2,975	5,149
Operating lease liabilities	(481)	(446)
Net cash used in operating activities	(132,433)	(78,794)
Cash flows from investing activities:
Purchases of property and equipment	(2)	(18)
Purchases of investments	(408,330)	(225,667)
Proceeds from sales and maturities of investments	182,239	27,120
Payments of milestones achieved pursuant to license agreements	(30,000)
Net cash used in investing activities	(256,093)	(198,565)
Cash flows from financing activities:
Payments of other offering costs for the ATM offering and equity offering	(527)
Payments of debt issuance costs for the senior secured term loan and convertible senior notes	(1,934)
Proceeds from exercise of stock options	1,173	1,821
Proceeds from issuance of common stock under employee stock purchase plan	592
Proceeds from senior secured term loan, net of discount	73,500
Proceeds from the issuance of convertible senior notes, inclusive of underwriters' exercise of the overallotment option in full, net of commissions	223,100
Net cash provided by financing activities	475,536	1,821
Effect of exchange rate changes on cash and cash equivalents	(1,074)	(288)
Net increase (decrease) in cash and cash equivalents	85,936	(275,826)
Cash and cash equivalents at beginning of period	110,641	319,832
Cash and cash equivalents at end of period	196,577	44,006
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets obtained under operating lease arrangements		$ 445
Deferred offering costs and debt issuance costs in accounts payable and accrued expenses	25
ATM Program
Cash flows from financing activities:
Proceeds from issuance of common stock, net of commissions	71,532
Equity Offering
Cash flows from financing activities:
Proceeds from issuance of common stock, net of commissions	$ 108,100

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2026	Dec. 31, 2025
Condensed Consolidated Balance Sheets
Preferred stock, par value (in dollar per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollar per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	175,000,000	175,000,000
Common stock, shares issued	63,330,747	54,485,518
Common Stock, shares outstanding	63,330,747	54,485,518

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2026

Accrued Expenses

Summary of accrued expenses


	June 30, 2026			December 31, 2025
External research, development and manufacturing expenses	$	43,632		$	38,855
Employee compensation and benefits		9,836			13,080
Professional and consultant fees		1,702			1,500
Interest expense on convertible senior notes		1,465			—
Income taxes payable		—			118
Other		771			870
Total accrued expenses	$	57,406		$	54,423

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2026

Fair Value Measurements

Schedule of information about the Company's assets and liabilities that are regularly measured and carried at fair value


			As of June 30, 2026
Description			Total Carrying Value		Quoted Prices in Active Market (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Observable Inputs (Level 3)
Assets:
Cash		$	115,202	$	115,202	$	—	$	—
Money market funds			81,375		81,375		—		—
Short-term investments:
Commercial paper			24,217		—		24,217		—
Corporate debt securities			78,902		—		78,902		—
Government securities			343,430		343,430		—		—
Long-term investments:
Corporate debt securities			16,648		—		16,648		—
Government securities			14,115		14,115		—		—
Total assets		$	673,889	$	554,122	$	119,767	$	—


			As of December 31, 2025
Description			Total Carrying Value		Quoted Prices in Active Market (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Other Observable Inputs (Level 3)
Assets:
Cash		$	13,038	$	13,038	$	—	$	—
Money market funds			97,603		97,603		—		—
Short-term investments:
Commercial paper			5,959		—		5,959		—
Corporate debt securities			44,299		—		44,299		—
Government securities			182,293		182,293		—		—
Long-term investments:
Corporate debt securities			1,467		—		1,467		—
Government securities			15,805		15,805		—		—
Total assets		$	360,464	$	308,739	$	51,725	$	—

Summary of available-for-sale securities

The following table summarizes the available-for-sale securities (in thousands):


	As of June 30, 2026
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Commercial paper	$	24,236	$	—	$	(19)	$	24,217
Corporate debt securities		95,670		2		(122)		95,550
Government securities		358,340		1		(796)		357,545
Total	$	478,246	$	3	$	(937)	$	477,312


	As of December 31, 2025
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Commercial paper	$	5,957	$	2	$	—	$	5,959
Corporate debt securities		45,740		28		(2)		45,766
Government securities		197,939		162		(3)		198,098
Total	$	249,636	$	192	$	(5)	$	249,823

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Net Loss Per Share

6 Months Ended

Jun. 30, 2026

Net Loss Per Share

Net Loss Per Share

12.Net Loss Per Share

The Company’s potentially dilutive securities, which include stock options, RSUs, convertible senior notes, and the 2,000,000 shares of common stock to be issued to InnoCare, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following shares from the computation of diluted net loss as of June 30, 2026 and 2025 because including them would have had an anti-dilutive effect:


	June 30,
	2026	2025
Options to purchase common stock	12,645,400	10,615,469
Unvested RSUs	1,263,694	511,100
Common stock to be issued to InnoCare	2,000,000	—
Shares of common stock underlying convertible senior notes outstanding¹	8,679,234	—

¹Represents conversion rate, as of June 30, 2026, of 37.7358 shares of common stock per $1,000 principal amount of notes.

Other Non-Current Assets (Tables)

6 Months Ended

Jun. 30, 2026

Other Non-Current Assets

Summary of other non-current assets


	June 30, 2026			December 31, 2025
Clinical trial deposits	$	15,716		$	12,882
Deferred offering costs		486			709
Other		87			218
Total other assets	$	16,289		$	13,809

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock ATM Program	Common Stock Equity Offering	Common Stock	Additional Paid-in Capital ATM Program	Additional Paid-in Capital Equity Offering	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	ATM Program	Equity Offering	Total
Balance at the beginning at Dec. 31, 2024			$ 4			$ 699,651	$ 194	$ (387,391)			$ 312,458
Balance at beginning (in shares) at Dec. 31, 2024			41,793,412
Changes in Stockholders' Equity (Deficit)
Exercises of common stock options						99					99
Exercises of common stock options (in shares)			28,475
Stock-based compensation expense						5,386					5,386
Unrealized gain (loss) on investments							12				12
Foreign currency translation adjustment							(65)				(65)
Net loss								(33,573)			(33,573)
Balance at end at Mar. 31, 2025			$ 4			705,136	141	(420,964)			284,317
Balance at end (in shares) at Mar. 31, 2025			41,821,887
Balance at the beginning at Dec. 31, 2024			$ 4			699,651	194	(387,391)			312,458
Balance at beginning (in shares) at Dec. 31, 2024			41,793,412
Changes in Stockholders' Equity (Deficit)
Unrealized gain (loss) on investments											42
Foreign currency translation adjustment											(330)
Net loss											(85,796)
Balance at end at Jun. 30, 2025			$ 4			712,903	(94)	(473,187)			239,626
Balance at end (in shares) at Jun. 30, 2025			42,088,697
Balance at the beginning at Mar. 31, 2025			$ 4			705,136	141	(420,964)			284,317
Balance at beginning (in shares) at Mar. 31, 2025			41,821,887
Changes in Stockholders' Equity (Deficit)
Exercises of common stock options						1,722					1,722
Exercises of common stock options (in shares)			266,810
Stock-based compensation expense						6,045					6,045
Unrealized gain (loss) on investments							30				30
Foreign currency translation adjustment							(265)				(265)
Net loss								(52,223)			(52,223)
Balance at end at Jun. 30, 2025			$ 4			712,903	(94)	(473,187)			239,626
Balance at end (in shares) at Jun. 30, 2025			42,088,697
Balance at the beginning at Dec. 31, 2025			$ 5			1,007,331	(64)	(765,128)			242,144
Balance at beginning (in shares) at Dec. 31, 2025			54,485,518
Changes in Stockholders' Equity (Deficit)
Exercises of common stock options						367					367
Exercises of common stock options (in shares)			25,767
Issuance of common stock		$ 1		$ 71,186	$ 93,644				$ 71,186	$ 93,645
Issuance of common stock (in shares)	2,827,723	5,000,000
Stock-based compensation expense						9,195					9,195
Purchases of common stock under the employee Stock purchase plan						592					592
Purchases of common stock under the Employee stock purchase plan (in shares)			44,369
Unrealized gain (loss) on investments							(341)				(341)
Foreign currency translation adjustment							28				28
Net loss								(80,987)			(80,987)
Balance at end at Mar. 31, 2026			$ 6			1,182,315	(377)	(846,115)			335,829
Balance at end (in shares) at Mar. 31, 2026			62,383,377
Balance at the beginning at Dec. 31, 2025			$ 5			1,007,331	(64)	(765,128)			$ 242,144
Balance at beginning (in shares) at Dec. 31, 2025			54,485,518
Changes in Stockholders' Equity (Deficit)
Exercises of common stock options (in shares)											103,592
Unrealized gain (loss) on investments											$ (1,121)
Foreign currency translation adjustment											44
Net loss											(192,443)
Balance at end at Jun. 30, 2026			$ 6			1,205,803	(1,141)	(957,571)			247,097
Balance at end (in shares) at Jun. 30, 2026			63,330,747
Balance at the beginning at Mar. 31, 2026			$ 6			1,182,315	(377)	(846,115)			335,829
Balance at beginning (in shares) at Mar. 31, 2026			62,383,377
Changes in Stockholders' Equity (Deficit)
Exercises of common stock options						806					806
Exercises of common stock options (in shares)			77,825
Vesting of restricted stock units (in shares)			119,545
Issuance of common stock					$ 14,063					$ 14,063
Issuance of common stock (in shares)		750,000
Stock-based compensation expense						8,619					8,619
Unrealized gain (loss) on investments							(780)				(780)
Foreign currency translation adjustment							16				16
Net loss								(111,456)			(111,456)
Balance at end at Jun. 30, 2026			$ 6			$ 1,205,803	$ (1,141)	$ (957,571)			$ 247,097
Balance at end (in shares) at Jun. 30, 2026			63,330,747

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2026

Net Loss Per Share

Schedule of anti-dilutive securities excluded from the computation of diluted net loss per share


	June 30,
	2026	2025
Options to purchase common stock	12,645,400	10,615,469
Unvested RSUs	1,263,694	511,100
Common stock to be issued to InnoCare	2,000,000	—
Shares of common stock underlying convertible senior notes outstanding¹	8,679,234	—

¹Represents conversion rate, as of June 30, 2026, of 37.7358 shares of common stock per $1,000 principal amount of notes.

Net Loss Per Share - Anti-dilutive Securities (Details)	6 Months Ended
Net Loss Per Share - Anti-dilutive Securities (Details)	Jun. 30, 2026 shares	Jun. 30, 2025 shares
Net Loss Per Share
Anti-dilutive securities excluded from computation of diluted net (loss) per share	8,679,234
Options to purchase common stock
Net Loss Per Share
Anti-dilutive securities excluded from computation of diluted net (loss) per share	12,645,400	10,615,469
Unvested restricted stock units
Net Loss Per Share
Anti-dilutive securities excluded from computation of diluted net (loss) per share	1,263,694	511,100
Common stock to be issued to InnoCare
Net Loss Per Share
Anti-dilutive securities excluded from computation of diluted net (loss) per share	2,000,000
Convertible Debt Securities
Net Loss Per Share
Conversion ratio	37.7358

Segment Information

6 Months Ended

Jun. 30, 2026

Segment Information

Segment Information

15.Segment Information

The Company manages its operations on a consolidated basis as a single reportable segment focused on the research and development of immunology-based therapies. The accounting policies of the single reportable segment are identical to those described in Note 1, Nature of Business, to these unaudited condensed consolidated financial statements. When evaluating the Company’s financial performance, the Company’s chief operating decision-maker (the “CODM”), its Chief Executive Officer regularly reviews consolidated net loss, total expense and direct expenses by program and compared to budget. The CODM allocates resources based on the Company’s available cash resources, and forecasted expenditures on a consolidated basis, as well as an assessment of the probability of success of its research and development activities on a program basis. Segment asset information regularly provided to the CODM is consistent with that reported on the consolidated balance sheets with particular emphasis on the Company’s available liquidity, including its cash, cash equivalents and investment balances. Revenue is primarily attributed to individual countries based on the entity owning the license. During the three and six months ended June 30, 2026, the Company recognized $1.0 million of revenue, which was attributed to Zenas HK. During the three months ended June 30, 2025, the Company did not recognize any revenue and for the six months ended June 30, 2025, the Company recognized $10.0 million of revenue which was attributed to Zenas HK.

The following table presents certain financial data for the Company’s reportable segment for the three and six months ended June 30, 2026 and 2025 (in thousands):


		For the three months ended June 30,				For the six months ended June 30,
		2026		2025		2026		2025
Revenue	$	1,000	$	—	$	1,000	$	10,000
Less:
Direct research and development expenses:¹
Obexelimab		29,394		29,894		61,154		53,254
Orelabrutinib		11,206		—		21,307		—
Other programs (ZB002, ZB004, ZB014, ZB021 & ZB022)		1,458		400		2,026		736
Partnered regional programs (ZB001 & ZB005)		(24)		(137)		(24)		(37)
Unallocated research and development²		17,018		10,757		31,932		20,295
General and administrative³		10,988		8,204		21,800		16,814
Acquired in-process research and development⁴		30,000		—		30,000		—
Stock-based compensation		8,619		6,045		17,814		11,431
Other segment items⁴		3,797		(2,940)		7,434		(6,697)
Segment net loss	$	(111,456)	$	(52,223)	$	(192,443)	$	(85,796)

³General and administrative expenses primarily consist of professional fees, depreciation expense, facilities expenses as well as all other personnel costs, excluding stock-based compensation.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details