0001937653-26-000015 | 10-K | XBRL Viewer

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Stockholders' Equity - Schedule of Non-Vested Stock Option Activity (Details)	12 Months Ended
	Dec. 31, 2025 $ / shares shares	Dec. 31, 2025 $ / shares shares
Number of options
Non-vested, beginning balance (in shares)	100,967	100,967
Options granted (in shares)	0	0
Options vested (in shares)	(72,760)	(72,760)
Options forfeited and cancelled (in shares)	(9,861)	(9,861)
Non-vested, ending balance (in shares)	18,346	18,346
Weighted-average grant date fair value
Non-vested, beginning balance (in dollars per share) \| (per share)	$ 5.08	$ 7.31
Options granted (in dollars per share) \| (per share)	0	0
Options vested (in dollars per share) \| (per share)	5.85	8.02
Options forfeited and cancelled (in dollars per share) \| (per share)	4.12	5.64
Non-vested, ending balance (in dollars per share) \| (per share)	$ 3.95	$ 5.42
Share-based Payment Arrangement, Option
Number of options
Non-vested, beginning balance (in shares)	4,147,288	4,147,288
Options granted (in shares)	2,467,225	2,467,225
Options vested (in shares)	(2,086,563)	(2,086,563)
Options forfeited and cancelled (in shares)	(474,733)	(474,733)
Non-vested, ending balance (in shares)	4,053,217	4,053,217
Weighted-average grant date fair value
Non-vested, beginning balance (in dollars per share) \| $ / shares	$ 6.65
Options granted (in dollars per share) \| $ / shares	8.76
Options vested (in dollars per share) \| $ / shares	6.72
Options forfeited and cancelled (in dollars per share) \| $ / shares	6.36
Non-vested, ending balance (in dollars per share) \| $ / shares	$ 7.84

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Dec. 31, 2025
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recent accounting pronouncements adopted In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments require disclosure of specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold and further disaggregation of income taxes paid for individually significant jurisdictions. The ASU is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The standard is to be applied on a prospective basis, with the option for retrospective application. The Company has adopted this accounting pronouncement on the accompanying financial statements prospectively to the current annual period. Prior period disclosures have not been adjusted to reflect the new disclosure requirements. See note 13 Income Taxes in the accompanying notes to the consolidated financial statements for further detail. Recent accounting pronouncements not yet adopted In November 2024, the FASB issued ASU 2024-03, Income Statement Reporting – Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40), Disaggregation of Income Statement Expenses. The standard update improves the disclosures about a public business entity’s expenses by requiring more detailed information about the types of expenses (including purchases of inventory, employee compensation, depreciation and amortization) included within income statement expense captions. The guidance will be effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The standard updates are to be applied prospectively with the option for retrospective application. The Company is currently evaluating the impact of adoption of the standard update on its consolidated financial statements.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

Liabilities - Schedule of Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Payables and Accruals [Abstract]
Liability from in-licensing agreements	$ 278	$ 447
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term liabilities (note 9)	Other long-term liabilities (note 9)
Finance lease liability (note 14)	$ 0	$ 28
Other	0	448
Total	$ 278	$ 923

Cover Page - USD ($)	12 Months Ended
Cover Page - USD ($)	Dec. 31, 2025	Feb. 26, 2026	Jun. 30, 2025
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-41535
Entity Registrant Name	ZYMEWORKS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	88-3099146
Entity Address, Address Line One	108 Patriot Drive
Entity Address, Address Line Two	Suite A
Entity Address, City or Town	Middletown
Entity Address, State or Province	DE
Entity Address, Postal Zip Code	19709
City Area Code	302
Local Phone Number	274-8744
Title of 12(b) Security	Common Stock, $0.00001 par value per share
Trading Symbol	ZYME
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 649,500,000
Entity Common Stock, Shares Outstanding		73,749,607
Documents Incorporated by Reference	.
Amendment Flag	false
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Entity Central Index Key	0001937653

Leases - Schedule of Future Minimum Lease Payment Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Leases [Abstract]
Within 1 year	$ 4,285
1 to 2 years	4,015
2 to 3 years	3,658
3 to 4 years	5,362
4 to 5 years	2,709
Thereafter	2,935
Total operating lease payments	22,964
Imputed interest	(4,697)
Total operating lease liabilities	$ 18,267	$ 18,478

Leases (Tables)

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Schedule of Balance Sheet Classification of Lease Liabilities

The balance sheet classification of the Company’s lease liabilities was as follows:


	December 31, 2025			December 31, 2024
Operating lease liabilities:
Current portion	$	3,471		$	2,740
Long-term portion	14,796			15,738
Total operating lease liabilities	$	18,267		$	18,478
Finance lease liabilities:
Current portion included in other current liabilities	—			28
Long-term portion included in other long-term liabilities	—			28
Total finance lease liabilities	—			56
Total lease liabilities	$	18,267		$	18,534

Weighted average remaining lease term:
Operating leases	5.2 years			6.4 years
Weighted average discount rate:
Operating leases in U.S. dollars	5.9		%	5.4		%
Operating leases in Canadian dollars	4.8		%	4.8		%

Schedule of Maturities of Operating Lease Liabilities

As of December 31, 2025, the maturities of the Company’s operating lease liabilities were as follows:


	Operating leases
Within 1 year	$	4,285
1 to 2 years	4,015
2 to 3 years	3,658
3 to 4 years	5,362
4 to 5 years	2,709
Thereafter	2,935
Total operating lease payments	22,964
Less:
Imputed interest	(4,697)
Operating lease liabilities	$	18,267

Schedule of Cost Components of Operating Leases

The cost components of the operating leases were as follows:


	Year Ended December 31,
	2025		2024		2023
Lease expenses:
Operating lease expense	$	3,355	$	2,447	$	7,292
Variable lease expense	2,257		1,969		1,637
Termination of long-term facility lease in Seattle, net	—		1,033		—
	$	5,612	$	5,449	$	8,929

Liabilities - Schedule of Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Payables and Accruals [Abstract]
Trade payables	$ 4,403	$ 3,903
Accrued research and development expenses	19,225	43,114
Goods and services tax payable	425	1,250
Employee compensation and related accruals	8,828	6,222
Fair value of liability classified stock options	844	1,264
Accrued legal, professional fees and other	2,621	4,085
Total	$ 36,346	$ 59,838

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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-Topic 946
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-Paragraph 1
-Subparagraph (SX 210.6-04(9)(e))
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-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 5C
-Subparagraph (SX 210.12-13C(Column H)(Footnote 7))
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Reference 29: 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 31: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (SX 210.12-13(Column G)(Footnote 8))
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+ Details

Income Taxes - Additional Information (Details) - USD ($)	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Line Items]
Net operating loss carry forwards	$ 737,000,000.0	$ 658,000,000.0
Unrecognized tax benefits that would impact effective tax rate	0	0	$ 0
Research Tax Credit Carryforward
Income Tax Disclosure [Line Items]
Tax credit carryforward, amount not subject to expiration	121,000,000.0	108,600,000
Tax credit carryforward, amount subject to expiration	1,100,000	900,000
Investment Tax Credit Carryforward
Income Tax Disclosure [Line Items]
Tax credit carryforward, amount subject to expiration	$ 28,000,000.0	$ 25,000,000.0

Stockholders' Equity - Schedule of Stock-based Compensation Expense for Equity Classified Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 12,849	$ 8,382	$ 2,404
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 14,687	$ 9,041	$ 5,316

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (f)(2)(i)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 35
-Paragraph 1D
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
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Reference 25: http://www.xbrl.org/2003/role/disclosureRef
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Reference 26: 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 29: http://www.xbrl.org/2003/role/disclosureRef
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Schedule of Loss Before Provision for Income Taxes

Loss before provision for income taxes was as follows:


	Year Ended December 31,
	2025
United States	$	(16,809)
Foreign	(62,945)
Loss before income taxes	$	(79,754)

Schedule of Income Tax Expense

Income tax expense is comprised of the following:


	Year Ended December 31,
	2025
Current tax provision:
Federal	482
State	(15)
Foreign	(898)
Total current tax expense	(431)

Deferred tax provision:
Federal	(845)
State	—
Foreign	(100)
Total deferred tax expense	(945)

Provision for income taxes	$	(1,376)


	Year Ended December 31,
	2024		2023
Current income tax expense	$	(5,393)	$	(189)
Deferred income tax (expense) recovery	(691)		757
Income tax (expense) recovery	$	(6,084)	$	568

Schedule of Effective Income Tax Rate Reconciliation

A reconciliation of the provision for income taxes to the amount computed by applying the 21% statutory U.S. federal income tax rate to income before income taxes after the adoption of ASU 2023-09 is as follows:


	Year Ended December 31,
	2025
	$	Percent
U.S. Federal statutory income tax rate	16,748	21.0	%
State & local income tax, net of federal income tax effect (1)	(15)	—	%
Foreign tax effects
Canada
Tax rate differential	(3,980)	(5.0)	%
Provincial tax rate differential	7,642	9.6	%
Changes in valuation allowance	(15,682)	(19.7)	%
Effect of cross-border laws	(1,921)	(2.4)	%
SR&ED Tax Credits	2,971	3.7	%
Stock Based Compensation	(4,065)	(5.1)	%
Other	91	0.1	%
United Kingdom
Stock Based Compensation	1,047	1.3	%
Other	(16)	—	%
Other foreign jurisdictions	(208)	(0.2)	%
Enactment of new tax laws	—	—	%
Effect of cross-border laws
Foreign Base Company Income	(2,006)	(2.5)	%
Other	—	—	%
Tax Credits	635	0.8	%
Changes in valuation allowance	(3,237)	(4.1)	%
Non-taxable or non-deductible items	(122)	(0.2)	%
Changes in unrecognized tax benefits	(97)	(0.1)	%
Other	839	1.1	%
Effective Income Tax Rate	(1,376)	(1.7)	%

(1) State taxes in New York, New Jersey, and Texas made up the majority of the tax effect in this category for the year ended December, 31 2025.

A reconciliation of the provision for income taxes to the amount computed by applying the 21% statutory U.S. federal income tax rate to income before income taxes for years prior to the adoption of ASU 2023-09 is as follows:


	Year Ended December 31,
	2024		2023
Computed taxes at United States statutory income tax rate	$	24,466	$	25,041
Non-deductible expenses	(10,508)		(2,696)
Difference between domestic and foreign tax rate	5,360		5,976
Adjustments to prior year	524		48,724
Change in valuation allowance	(28,882)		(78,668)
Change in recognition and measurement of tax positions	(38)		(14)
Changes due to SR&ED and research credits	3,102		2,661
Other	(108)		(456)
Income tax (expense) recovery	$	(6,084)	$	568

Schedule of Significant Components of the Deferred Income Tax Assets and Liabilities

The significant components of the deferred income tax assets and liabilities are as follows:


	December 31, 2025		December 31, 2024
Deferred tax assets:
Non-capital losses carried forward	$	199,946	$	177,660
Deferred revenue	4,596		10,852
Share issuance costs	666		1,360
Property and equipment	—		71
Intangible assets	5,271		4,539
Research and development deductions and credits	57,097		50,415
Stock options	7,724		8,388
Operating lease liability	4,657		4,761
Other	42		202
	$	279,999	$	258,248
Deferred tax liabilities:
Property and equipment	(243)		(174)
Operating lease right-of-use assets	(4,024)		(4,294)
Outside basis difference in foreign subsidiary	(2,414)		(2,429)
Stock options	—		(2,333)
Other	(182)		(176)
	$	(6,863)	$	(9,406)
	273,136		248,842
Less: valuation allowance	(274,457)		(249,218)
Net deferred tax (liabilities) assets	$	(1,321)	$	(376)
Deferred tax assets	$	4,707	$	4,385
Deferred tax liabilities	(6,028)		(4,761)
Net deferred tax (liabilities) assets	$	(1,321)	$	(376)

Schedule of Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits

A reconciliation of total unrecognized tax benefits for the years ended December 31, 2025, 2024, and 2023 are as follows:


	Year Ended December 31,
	2025		2024		2023
Balance, beginning of year	$	3,115	$	3,077	$	3,063
Gross increases related to prior year tax positions	2,364		—		—
Gross decreases to tax positions in prior periods	—		—		—
Gross increases to current period tax positions	97		38		14
Gross decreases due to settlements with taxing authorities	—		—		—
Gross decreases due to statute of limitations lapse	—		—		—
Balance, end of year	$	5,576	$	3,115	$	3,077

Schedule of Cash Income Taxes Paid

The amounts of cash income taxes paid by the Company were as follows:


	Year Ended December 31,
	2025
Federal	$	213
State	17
Foreign
Ireland	72
United Kingdom	1,030
All other foreign	18
Income taxes, net of amounts refunded	$	1,350

Research, Collaboration and Licensing Agreements - Schedule Of Collaborative Arrangements and Noncollaborative Arrangement Transactions (Details) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	May 31, 2025	Mar. 31, 2025	Jan. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				$ 105,965	$ 76,304	$ 76,012
Development support payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				0	168	2,864
Jazz: \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				0	25,000	0
Jazz: \| Development support payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				5,616	2,835	52,619
Jazz: \| Drug supply for ongoing studies
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				6,548	19,228	25,662
Jazz: \| Credit note for amendment of program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				0	0	(20,100)
Jazz: \| Other drug supply
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				2,103	15,464	13,350
Jazz: \| Royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				2,481	100	0
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations	$ 20,000			20,000	8,000	0
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Development support payments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				0	0	537
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Other drug supply
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				762	3,009	1,080
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				271	0	0
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Recognition of deferred revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				18,334	0	0
Johnson & Johnson Innovative Medicine (previously known as Janssen Biotech, Inc.) (“J&J”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				25,000	0	0
GlaxoSmithKline Intellectual Property Development Ltd. (“GSK”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations			$ 14,000	14,000	2,500	0
Bristol-Myers Squibb (“BMS”): \| Option Exercise Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				7,500	0	0
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations		$ 3,100		3,100	0	0
Merck Sharp & Dohme LLC (“Merck”) \| Research period extension fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				$ 250	$ 0	$ 0

Cash, Cash Equivalents and Marketable Securities

12 Months Ended

Dec. 31, 2025

Investments, All Other Investments [Abstract]

Cash, Cash Equivalents and Marketable Securities

The following table summarizes the Company's marketable securities as of December 31, 2025:


	December 31, 2025
	Amortized Cost		Unrealized Gain (Loss)		Fair Value
Short-term marketable securities:
Contractual maturity of one year or less:
Guaranteed investment certificates (“GICs”) and mutual funds	$	21,920	$	—	$	21,920
U.S. Treasury notes	41,263		36		41,299
Corporate debt securities	124,272		149		124,421
	187,455		185		187,640
Long-term marketable securities:
Contractual maturity of one to three years:
Corporate debt securities	41,388		399		41,787

	41,388		399		41,787

	$	228,843	$	584	$	229,427

The following table summarizes the Company's marketable securities as of December 31, 2024:


	December 31, 2024
	Amortized Cost		Unrealized Gain (Loss)		Fair Value
Short-term marketable securities:
Contractual maturity of one year or less:
GICs	$	37,166	$	—	$	37,166
U.S. Treasury notes	71,500		72		71,572
Corporate debt securities	50,993		(58)		50,935
	159,659		14		159,673
Long-term marketable securities:
Contractual maturity of one to three years:
Corporate debt securities	65,461		(153)		65,308
Contractual maturity of three to four years:
Corporate debt securities	18,295		(156)		18,139
	98,735		(307)		98,428

	$	258,394	$	(293)	$	258,101

The unrealized losses on the Company’s available-for-sale securities as of December 31, 2025 and 2024 were not material and were caused by fluctuations in market values and interest rates as a result of the economic environment. The Company concluded that an allowance for credit losses was unnecessary as of December 31, 2025 and 2024 because the decline in the market value was attributable to changes in market conditions and not credit quality, and that it is neither management’s intention to sell nor is it more likely than not that the Company will be required to sell these investments prior to recovery of their cost basis or recovery of fair value. There was no material realized gain or loss on available-for-sale securities in the periods presented.

The following tables present information about the Company’s assets that are measured at fair value on a recurring basis, and indicate the fair value hierarchy of the valuation techniques used to determine such fair value:


	December 31, 2025								December 31, 2024
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash and cash equivalents:
Cash							$	8,968							$	34,620
Cash equivalents:
Money market funds	$	32,189	$	—	$	—	$	32,189	$	16,398	$	—	$	—	$	16,398
GICs	—		—		—		—		15,085		—		—		15,085
	32,189		—		—		41,157		31,483		—		—		66,103

Marketable securities:
GICs and mutual funds	21,920		—		—		21,920		37,166		—		—		37,166
U.S. Treasury notes	41,299		—		—		41,299		86,553		—		—		86,553
Corporate debt securities	—		166,208		—		166,208		—		134,382		—		134,382
	63,219		166,208		—		229,427		123,719		134,382		—		258,101

	$	95,408	$	166,208	$	—	$	270,584	$	155,202	$	134,382	$	—	$	324,204

Research, Collaboration and Licensing Agreements - GlaxoSmithKline Intellectual Property Development Ltd. (Details)		12 Months Ended
	Dec. 01, 2015 USD ($) program antibody	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 105,965,000	$ 76,304,000	$ 76,012,000
Glaxo Smith Kline Intellectual Property Development Ltd \| License Agreement \| Commercial and Development Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 0
Glaxo Smith Kline Intellectual Property Development Ltd \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody	10
Collaborative arrangement, number of products \| program	4
Glaxo Smith Kline Intellectual Property Development Ltd \| Maximum \| Eligible to Receive \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 1,100,000,000
Glaxo Smith Kline Intellectual Property Development Ltd \| Maximum \| Eligible to Receive \| License Agreement \| Collaborative Arrangement \| Research, Development and Commercial Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 110,000,000.0

Intangible Assets

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

Intangible assets consist of the following:


	December 31,
	2025		2024
Research licenses	$	14,936	$	14,936
Computer software	11,501		10,670
Intangible assets	26,437		25,606
Less accumulated amortization	(25,087)		(21,030)
Intangible assets, net	$	1,350	$	4,576

Amortization expense on intangible assets for the years ended December 31, 2025, 2024 and 2023 was $4,056, $4,496 and $2,702, respectively.

At December 31, 2025, amortization expense on capitalized intangible assets is estimated to be as follows for the next five years:


	Amortization expense
2026	$	703
2027	490
2028	157
Thereafter	—
	$	1,350

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation

The consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). The consolidated financial statements include the accounts of Zymeworks Inc. and its wholly owned subsidiaries, Zymeworks BC Inc., Zymeworks Biopharmaceuticals Inc., Zymeworks Pharmaceuticals Limited (Ireland), Zymeworks Lifesciences Pte. Ltd. (Singapore), Zymeworks CallCo ULC, Zymeworks ExchangeCo Ltd., Zymeworks Management Inc. (including this entity's branch in the United Kingdom) and Zymeworks Zanidatamab Inc. (refer to note 11). All inter-company accounts and transactions have been eliminated on consolidation.

All amounts expressed in the consolidated financial statements of the Company and the accompanying notes thereto are expressed in thousands of U.S. dollars, except for share and per share data and where otherwise indicated. References to “$” are to U.S. dollars and references to “C$” are to Canadian dollars. Certain prior year amounts have been reclassified for consistency with the current period presentation. These reclassifications had no effect on the reported results of operations.

Foreign Currency

The functional currency of the Company is the U.S. dollar. Transactions denominated in foreign currencies are remeasured at the approximate exchange rate prevailing on the date of the transaction. At period end, monetary assets and liabilities denominated in foreign currencies are remeasured into U.S. dollars using exchange rates in effect at the balance sheet date. Resulting foreign exchange gains and losses are reflected in the Consolidated Statements of (Loss) Income and Comprehensive (Loss) Income.

Use of Estimates

The preparation of consolidated financial statements in accordance with U.S. GAAP requires the Company to make estimates and judgments in certain circumstances that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. On an ongoing basis, the Company evaluates its estimates, most notably those related to revenue recognition including estimated timing of completion of performance obligations required to meet revenue recognition criteria, accrual of expenses including clinical and preclinical study expense accruals, stock-based compensation, valuation allowance for deferred taxes, measurement of contingent consideration liabilities, and other contingencies. Management bases its estimates on historical experience and on various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from these estimates.

Revenue Recognition

Accounting Standards Codification Topic 606, Revenue from Contracts with Customers (“ASC 606”) applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments. In accordance with ASC 606, the Company recognizes revenue when the Company’s customer obtains control of promised goods or services, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods or services.

The Company applied ASC 606 to all revenue arrangements to date. For collaborative arrangements that fall within the scope of ASC 808, Collaborative Arrangements (“ASC 808”), the Company applies the revenue recognition model under ASC 606 to part or all of the arrangements, when deemed appropriate. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company determines which elements of the arrangement are within the scope of ASC 808 and which elements are within the scope of ASC 606, which may require application of judgment.

In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its agreements, the Company performs the following steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations including whether they are distinct; (iii) determine the transaction price, including uncertainties related to variable consideration; (iv) allocate the transaction price to the performance obligations based on the stand-alone selling prices; and (v) recognize revenue when or as the Company satisfies each performance obligation and when collectability is probable.

The Company only applies the five-step model to contracts when it is probable that the Company will collect the consideration that it is entitled to in exchange for the goods and services transferred to the customer. At contract inception, the Company assesses the goods or services promised within each contract that falls under the scope of Topic 606, to identify distinct performance obligations. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when or as the performance obligation is satisfied.

The Company has entered into a number of collaboration and licensing agreements. Promised deliverables within these agreements may include: (i) grants of licenses, or options to obtain licenses, to the Company’s intellectual property, (ii) research and development services, (iii) drug product manufacturing, and (iv) participation on joint research and/or development committees. The terms of these agreements typically include one or more of the following types of payments to the Company:

•non-refundable, upfront license and platform technology access fees;

•research, development and regulatory milestone payments;

•research support, development and other payments; and

•royalties and commercial milestone payments.

If the expectation at contract inception is such that the period between payment by the licensee and the completion of related performance obligations will be one year or less, the Company assumes that the contract does not have a significant financing component.

When applying the revenue recognition criteria of ASC 606 to license and collaboration agreements, the Company may be required to apply significant judgment when evaluating whether contractual obligations represent distinct performance obligations including understanding the nature and significance of the contractual obligations and their standalone selling prices, determining when performance obligations have been met, assessing the recognition and future reversal of variable consideration, and determining and applying appropriate methods of measuring progress for performance obligations satisfied over time. The accounting for the modification to existing contracts with customers arising from licensing and collaboration arrangements requires management to apply significant judgment when evaluating whether the modification to financial terms

is related to distinct performance obligations remaining in the amended collaboration agreement. These judgments are discussed in more detail in the following paragraphs for each type of payment received by the Company under the terms of the license and collaborations agreements.

Non-refundable, upfront license and platform technology access fees

If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, upfront fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are not distinct from other promises, the Company uses judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, upfront fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the related revenue recognition accordingly.

Research, development and regulatory milestone payments

At the inception of each arrangement that includes research, development or regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. When it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company re-evaluates the probability of achievement of such development milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration and other revenues and earnings in the period of adjustment. The probability of successfully achieving the criteria for the milestone payments is highly uncertain. Consequently, there is a significant risk that the Company may not earn all of the milestone payments from each of its strategic partners.

Research and development milestones in the Company’s collaboration agreements may include some, but not necessarily all, of the following types of events:

• completion of preclinical research and development work leading to selection of product candidates;

• initiation of Phase 1, Phase 2 and Phase 3 clinical trials; and

• achievement of certain other technical, scientific or development criteria.

Regulatory milestone payments may include the following types of events:

• filing of regulatory applications for marketing approval in the United States, Europe or Japan, including Investigational New Drug (“IND”) applications and Biologics License Application (“BLA”); and

• marketing approval in major markets, such as the United States, Europe, Japan or China.

Research support, development and other payments

Payments by the licensees in exchange for research and development activities performed by the Company on behalf of the licensee are recognized as revenue upon performance of such activities at rates consistent with prevailing market rates. Payments for research and development supplies provided are recognized as revenue upon delivery of the supplies.

Supply of clinical trial drugs and comparator drugs

Amounts receivable by the Company for the provision of drugs to licensee or to clinical trials on behalf of licensee are recognized in revenue at a point in time when title to drugs has transferred to the licensee, which generally occurs upon shipment or delivery, depending on contractual terms.

Royalties and commercial milestone payments

For arrangements that include sales-based royalties, including commercial milestone payments based on pre-specified level of sales, the Company recognizes 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). Achievement of these royalties and commercial milestones may solely depend upon performance of the licensee. The Company started recognizing royalty income during the year ended December 31, 2024. The Company's commercial partner is obligated to report its net product sales and resulting royalty due to the Company within 60 days from the end of each quarter. The Company accrues royalty revenue based on historic product sales, royalty receipts and other relevant information as available and recognizes any adjustment when it receives royalty reports from its commercial partner in the subsequent period.

Contract assets and liabilities

Contract assets are mainly comprised of accrued revenue for which one of more performance obligations has been completed but not yet billed, which includes amounts billed and currently due from customers.

Contract liabilities are mainly comprised of deferred revenues. Amounts received prior to satisfying all revenue recognition criteria are recorded as deferred revenue in the Company’s consolidated financial statements. Amounts not expected to be recognized as revenue within the next twelve months of the consolidated balance sheet date are classified as long-term deferred revenue.

Modifications of contracts with customers

The Company accounts for a modification to a contract with a customer as a separate contract if both the scope of the contract increases because of the addition of promised goods or services that are distinct, and the price of the contract increases by an amount of consideration that reflects the Company’s stand-alone selling price of the additional promised goods or services. A modification that does not meet this criteria is accounted for as an adjustment to the existing contract, either prospectively or through a cumulative catch-up adjustment. The Company accounts for a contract modification prospectively if the remaining goods or services are distinct from the goods or services transferred before the modification, but the consideration for those goods or services does not reflect their stand-alone selling prices. Any changes in the transaction price that arise as a result of a contract modification that are not allocated to remaining goods or services are recognized as a cumulative catch-up adjustment.

Cash Equivalents

The Company considers all highly liquid investments purchased with original maturities of 90 days or less at the date of acquisition to be cash equivalents. Cash equivalents include guaranteed investment certificates (“GICs”) acquired from financial institutions and money market funds which are recorded at cost plus accrued interest, which approximates their fair value.

Investments

Marketable Securities

The Company's investments include high credit quality investment grade debt securities which comprise investments in U.S. Treasury notes and corporate debt securities. The Company classifies all of its investment grade debt securities as available-for-sale (note 5). Marketable securities also include GICs with original maturities of greater than 90 days. These investments are recorded at cost plus accrued interest, which approximates their fair value.

Unrealized fair value gains and losses for investments classified as available-for-sale are recorded through other comprehensive income (loss) in stockholders' equity. When the fair value of an available-for-sale security falls below the amortized cost basis it is evaluated to determine if any of the decline in value is attributable to credit loss. Decreases in fair value attributable to credit loss are recorded directly to the consolidated statement of (loss) income with a corresponding allowance for credit losses, limited to the amount that the fair value is below the amortized cost basis. If the credit quality subsequently improves the allowance is reversed up to a maximum of the previously recorded credit losses. When the Company intends to sell an impaired available-for-sale security, or if it is more likely than not that the Company will be required to sell the security prior to recovering the amortized cost basis, the entire fair value adjustment will immediately be recognized in the consolidated statement of (loss) income with no corresponding allowance for credit losses. Realized gains and losses and credit losses, if any, on available-for-sale securities are included in interest income (expense), based on the specific identification method. Available-for-sale securities are also adjusted for amortization of premiums and accretion of discounts to maturity, with such amortization and accretion included within interest income.

Marketable securities with remaining maturities of less than one year from the balance sheet date are classified as short-term investments and greater than one year from the balance sheet date are classified as long-term investments.

Accounts Receivable and Expected Credit Losses

Accounts receivable are recorded at invoiced amounts, net of any allowance for expected credit losses. The allowance for expected credit losses is the Company’s best estimate of the amount of probable credit losses in existing accounts receivable.

The Company evaluates the collectability of accounts receivable on a regular basis based upon various factors including the financial condition and payment history of customers, an overall review of collections experience on other accounts and economic factors or events expected to affect future collections experience. Expected credit losses on our accounts receivable were immaterial as at December 31, 2025 and 2024.

Financial Instruments

The Company evaluates financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level of classification each reporting period. This determination requires the Company to make subjective judgments as to the significance of inputs used in determining fair value and where such inputs lie within the fair value hierarchy.

Fair Value Measurements

The Company measures certain financial instruments and other items at fair value.

To determine fair value, the Company uses a fair value hierarchy that prioritizes the inputs, assumptions and valuation techniques used to measure fair value. The three levels of the fair value hierarchy are as follows:

• Level 1 inputs are unadjusted quoted market prices for identical instruments available in active markets.

• Level 2 inputs are inputs other than Level 1 prices, such as prices for a similar asset or liability that are observable either directly or indirectly. If the asset or liability has a contractual term, the input must be observable for substantially the full term. An example includes quoted market prices for similar assets or liabilities in active markets.

• Level 3 inputs are unobservable inputs for the asset or liability and will reflect management’s assessment about market assumptions that would be used to price the asset or liability.

Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. Changes in the observability of valuation inputs may result in a reclassification of levels for certain securities within the fair value hierarchy.

The Company’s financial instruments consist of cash and cash equivalents, short-term and long-term investments in marketable and other securities, accounts receivable, accounts payable and accrued liabilities, contingent consideration, finance and operating lease obligations, and other long-term liabilities.

The carrying values of cash and cash equivalents, accounts receivable and accounts payable and accrued liabilities approximate their fair values due to the near-term maturities of these financial instruments. All marketable securities are classified as available-for-sale and are recorded at fair value.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash and cash equivalents, short-term and long-term marketable securities and accounts receivable. Cash and cash equivalents and investments in marketable securities are invested in accordance with the Company’s cash investment policy with the primary objective being the preservation of capital and maintenance of liquidity. The cash investment policy includes guidelines on the quality of financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentration of credit risk. The Company limits its exposure to credit loss by placing its cash and cash equivalents and investments with high credit quality financial institutions.

At December 31, 2025, the maximum exposure to credit risk for accounts receivable was $4,638, 37% of which was from Jazz Pharmaceuticals Ireland Limited or Jazz Pharmaceuticals, Inc. (subsidiaries of Jazz Pharmaceuticals plc, collectively referred to as “Jazz”) (December 31, 2024: $55,815, 95% of which was from Jazz Pharmaceuticals Ireland Limited) and all accounts receivable are due within the next 12 months. As at December 31, 2025 and December 31, 2024, the Company has recognized nominal amounts of provision for expected credit losses in relation to accounts receivable.

Liquidity Risk

Liquidity risk is the risk that the Company will encounter difficulty in meeting the obligations associated with its financial liabilities that are settled by delivering cash or another financial asset. The Company’s short-term cash requirements are primarily to settle its financial liabilities, which consist primarily of accounts payable and accrued liabilities falling due within 45 days and current portion of lease obligations falling due within the next 12 months, with medium term requirements to invest in property and equipment and research and development. The Company’s principal sources of liquidity to settle its financial liabilities are cash, cash equivalents, short-term and long-term investments, collection of accounts receivable relating to research collaboration and license agreements and additional public and private equity offerings as required. The Company believes that these principal sources of liquidity are sufficient to fund its operations for at least the next 12 months.

Foreign Currency Risk

The Company incurs certain operating expenses in currencies other than the U.S. dollar and accordingly is subject to foreign exchange risk due to fluctuations in exchange rates. The Company does not use derivative instruments to hedge exposure to foreign exchange risk and therefore assumes the risk of future gains or losses in its consolidated statements of (loss) income. At December 31, 2025, the Company’s net monetary assets denominated in Canadian dollars were $4,337 (C$5,946) (December 31, 2024: $3,464 (C$4,982) net monetary liabilities).

The operating results and financial position of the Company are reported in U.S. dollars in the Company’s consolidated financial statements. The fluctuation of the U.S. dollar relative to the Canadian dollar and other foreign currencies will have an impact on the reported balances for net assets, net loss and stockholders’ equity in the Company’s consolidated financial statements.

Segment Information

The Company operates and manages its business in one segment, which is the Management of a portfolio of licensed healthcare assets and development of next-generation multifunctional biotherapeutics. Operating segments are defined as components of an enterprise about which separate discrete information is available for the chief operating decision maker (“CODM”), in deciding how to allocate resources and assessing performance.

Property and Equipment

Property and equipment are recorded at cost net of accumulated depreciation. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized in earnings. Repairs and maintenance costs are expensed as incurred.

The Company records depreciation using the straight-line method over the estimated useful lives of the property and equipment as follows:


Asset Class						Rate
Computer hardware						3 years
Office equipment						3 years
Furniture and fixtures						5 years
Laboratory equipment						7 years
Leasehold improvements						Shorter of the lease term or useful life

Property and equipment acquired or disposed of during the year are depreciated proportionately for the period they are in use.

Leases

The Company accounts for leases in accordance with ASC 842 Leases (“ASC 842”). The Company determines if an arrangement contains a lease at inception. Right-of-use (“ROU”) assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from that lease. For leases with a term greater than 12 months, ROU assets and liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. The lease term includes the option to extend the lease when it is reasonably certain the Company will exercise that option. When available, the Company uses the rate implicit in the lease to discount lease payments to present value. In the case the implicit rate is not available, the Company uses its incremental borrowing rate based on information available at the lease commencement date, to determine the present value of lease payments.

Patents and Intellectual Property Costs

Costs incurred to acquire patents and to prosecute and maintain intellectual property rights are expensed as incurred to general and administrative expense due to the uncertainty surrounding the drug development process and the uncertainty of future benefits. Patents and intellectual property acquired from third parties are capitalized and amortized over the remaining life of the patent, if related to approved products or if there are alternative future uses for the underlying technology. No patent or intellectual property costs have been capitalized to date.

Government Grants and Credits

Government grants are recognized where there is reasonable assurance that the grant will be received and all associated conditions will be complied with. Reimbursements of eligible research and development expenditures pursuant to government assistance programs are recorded as reductions of research and development costs when the related costs have been incurred and there is reasonable assurance regarding collection of the claim.

Grant claims not settled by the balance sheet date are recorded as receivables, provided their receipt is probable. The determination of the amount of the claim, and hence the receivable amount, requires management to make calculations based on its interpretation of eligible expenditures in accordance with the terms of the programs. The reimbursement claims submitted by the Company are subject to review by the relevant government agencies. The Company has used its best judgment and understanding of the related program agreements in determining the receivable amount.

The Company participates in SR&ED and Research Tax Credit Programs, two federal tax incentive programs that encourage Canadian and U.S. businesses to conduct research and development in Canada and in United States, respectively. The benefits of investment tax credits for scientific research and development expenditures are recognized in the year the qualifying expenditure is made provided there is reasonable assurance of recoverability. The refundable portion of investment tax credits are recorded as reductions to research and development expenditures.

Research and Development Costs

Research and development costs are expensed as incurred and include costs that the Company incurs for its own and for the Company’s strategic partners’ research and development activities. These costs primarily consist of expenses incurred under agreements with contract research organizations on the Company’s behalf, investigative sites and consultants that conduct the Company’s clinical trials, the cost of acquiring and manufacturing clinical trial materials and other allocated expenses, the cost of acquired research patents and intellectual property that do not meet the requirements for capitalization, employee related expenses, including salaries and benefits, stock-based compensation expense, and costs associated with nonclinical activities and regulatory approvals.

Clinical Trial Expense Accruals

Clinical trial expenses represent a significant component of research and development expenses and the Company outsources a significant portion of these activities to third party contract research organizations. Third-party clinical trial expenses include investigator fees, site costs, clinical research organization costs and other trial-related vendor costs. As part of preparing the consolidated financial statements, the Company estimates accrued liabilities for services that have been performed by clinical research organizations or investigator sites but have not yet been invoiced to the Company. When making these estimates, the Company uses operational and contractual information from third party service providers and operational data from internal personnel. For the year ended December 31, 2025, the Company recorded a change in estimate of $6,676 related to historical zanidatamab clinical trial accruals associated with studies that were transferred to Jazz (note 11). These clinical trial accruals reflected management's estimate of costs incurred prior to the Zymeworks BC collaboration agreement with Jazz. As the underlying studies were substantially completed by 2025 and clinical research organizations (“CRO”) confirmations were obtained in the fourth quarter of 2025, the Company determined that these accrual amounts are no longer expected to be invoiced. This adjustment resulted in a reduction of research and development expenses for the year.

Income Taxes

The Company accounts for income taxes using an asset and liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The measurement of deferred tax assets is reduced, if necessary, by the extent of a valuation allowance. The recognition of uncertain tax positions is evaluated based on whether it is considered more likely than not that the position taken, or expected to be taken, on a tax return will be sustained upon examination through

litigation or appeal. For those positions that meet the recognition criteria, they are measured as the largest amount that is more than 50% likely to be realized upon ultimate settlement.

Stock-Based Compensation

The Company recognizes stock-based compensation expense on equity and liability classified stock-based awards granted to employees, directors, and certain consultants. The Company measures the cost of such awards based on the fair value of the award, net of estimated forfeitures, and recognizes stock-based compensation expense in the consolidated statements of (loss) income and comprehensive (loss) income on a straight-line basis over the requisite service period. The requisite service period generally equals the vesting period of the awards. The fair values of stock option awards are estimated using the Black-Scholes option pricing model which uses various inputs including estimated fair value of the Company’s underlying common stock at the grant date, expected term, estimated volatility, risk-free interest rate and expected dividend yields of the Company’s common stock. The Company applies an estimated forfeiture rate derived from historical employee termination behavior. If the actual number of forfeitures differs from those estimated by management, adjustments to compensation expense may be required in future periods. The fair value of restricted stock units (“RSU”) is measured using the per share fair value of the Company’s common stock on the dates of grant.

Equity classified awards are measured using their grant date fair value. Liability classified awards are initially measured using their grant date fair value and are subsequently remeasured at fair value at each balance sheet date until exercised or cancelled, with changes in fair value recognized as compensation cost (ASC 718 awards) or other (expense) income (ASC 815 awards) for the period, while fair value changes below the grant date fair value of the original awards are recorded in additional paid-in capital.

Under ASC 718 Compensation—Stock Options (“ASC 718”), warrants or stock options with exercise price which is not denominated in: (a) the currency of a market in which a substantial portion of the Company’s equity securities trades, (b) the currency in which the individual’s pay is denominated, or (c) the Company’s functional currency, are required to be classified as liabilities. For awards accounted for under ASC 815 Derivatives and Hedging (“ASC 815”), any warrant or option that provides for an exercise price which is not denominated in the Company’s functional currency is required to be classified as a liability.

The Company has an employee stock purchase plan which is considered compensatory. Accordingly, the Company recognizes compensation expense on these awards based on their estimated grant date fair value using the Black-Scholes option pricing model. The Company recognizes compensation expense in the consolidated statements of loss and comprehensive loss on a straight-line basis over the requisite service period.

Stock Repurchases

As part of its stock repurchase programs, the Company adopted an accounting policy whereby the par value of each share is deducted from common stock and the remainder of the repurchase price is debited to accumulated deficit.

Business Combinations and Goodwill

Business combinations are accounted for using the acquisition method. The fair value of total purchase consideration is allocated to the fair values of identifiable tangible and intangible assets acquired and liabilities assumed, with the remaining amount being classified as goodwill. All assets, liabilities and contingent liabilities acquired or assumed in a business combination are recorded at their fair values at the date of acquisition. If the Company’s interest in the fair value of the acquiree’s net identifiable assets exceeds the cost of the acquisition, the excess is recognized in earnings or loss immediately. Transaction costs that are incurred in connection with a business combination, other than costs associated with the issuance of debt or equity securities, are expensed as incurred.

Goodwill is evaluated for impairment on an annual basis or more frequently if an indicator of impairment is present (note 6). As part of the impairment evaluation, the Company may elect to perform an assessment of qualitative factors. If this qualitative assessment indicates that it is more likely than not that the fair value of the reporting unit that includes the goodwill is less than its carrying value, then a quantitative impairment test would be prepared to compare the fair value to the carrying value and record an impairment charge if the carrying value exceeds the fair value.

Acquired In-Process Research and Development (IPR&D) and Definite-lived Intangible Assets

Acquired IPR&D represents the fair value assigned to research and development assets that have not reached technological feasibility. IPR&D is classified as an indefinite-lived intangible asset and is not amortized. IPR&D becomes definite-lived upon the completion or abandonment of the associated research and development efforts. All research and development costs incurred subsequent to the acquisition of IPR&D are expensed as incurred. Indefinite-lived intangible assets are reviewed for impairment on an annual basis or more frequently if an indicator of impairment is present. The Company may first perform a qualitative assessment to determine whether it is necessary to perform the quantitative impairment test.

Definite-lived intangible assets include computer software and a research license and are amortized on a basis which reflects the pattern in which the economic benefits are consumed. Amortization begins when the assets are put into use. If there is an event indicating that the carrying value of a definite-lived intangible asset may be impaired, then the Company will perform an impairment test. When an impairment test is performed, if the carrying value exceeds the recoverable value, based on the sum of undiscounted future cash flows, then such asset is written down to its fair value.

The Company records amortization using the straight-line method over the estimated useful lives of the definite-lived intangible assets as follows:


Asset Class						Rate
Software						3 years
Licensing agreements						Shorter of the licensing term or useful life

Net income (loss) per share

Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted average number of shares of common stock outstanding for the year, including the treatment of Exchangeable Shares and pre-funded warrants. Diluted net income (loss) per share attributable to common stockholders is computed by adjusting net income (loss) attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities, including outstanding stock options and warrants. Diluted net income (loss) per share attributable to common stockholders is computed by dividing the diluted net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the year, including potential dilutive shares of common stock assuming the dilutive effect of outstanding instruments. The treasury stock method is used to determine the dilutive effect of the Company’s stock option grants and warrants. ASC 260 Earnings Per Share requires an adjustment to the numerator for any income or loss related to liability classified warrants and stock options, if dilutive, if they are presumed to be share settled.

Commitment and Contingencies

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Commitments

The Company has entered into research collaboration agreements with strategic partners in the ordinary course of operations that may include contractual milestone payments related to the achievement of pre-specified research, development, regulatory and commercialization events and indemnification provisions, which are common in such agreements. Pursuant to the agreements, the Company is obligated to make research and development and regulatory milestone payments upon the occurrence of certain events and royalty payments based on net sales. The maximum amount of potential future indemnification is unlimited, however, the Company currently holds commercial and product liability insurance that limits the Company’s liability and may enable it to recover a portion of any future amounts paid. Historically, the Company has not made any indemnification payments under such agreements and believes that the fair value of these indemnification obligations is minimal. Accordingly, the Company has not recognized any liabilities relating to indemnification obligations for any period presented in the consolidated financial statements.

In connection with the Company’s 2016 Kairos acquisition, the Company may be required to make future payments of up to an

aggregate of C$8,500, consisting of (i) a C$2,500 payment when the first patient is dosed in the first Phase 2 trial and (ii) a C$6,000 payment when the first patient is dosed in the first Phase 3 trial, to CDRD Ventures Inc. (“CVI”) upon the direct achievement of certain development milestones for products incorporating certain Kairos intellectual property (such as zanidatamab zovodotin or other product candidates using our ZymeLink technology). In addition, CVI is eligible to receive low single-digit royalty payments from the Company on the net sales of such products. For out-licensed products and technologies incorporating certain Kairos intellectual property, the Company may also be required to pay CVI a mid-single digit percentage of certain future revenue. As of December 31, 2025, the contingent consideration had an estimated fair value of nil, (December 31, 2024: nil) (note 9).

The following table presents the changes in fair value of the Company’s liability for contingent consideration:


	Liability at the beginning of the period		Increase (decrease) in fair value of liability for contingent consideration	Amounts paid or transferred to payables	Liability at end of the period
Year ended December 31, 2025	$	—	—	—	$	—
Year ended December 31, 2024	$	1,878	(1,878)	—	$	—

Contingencies

From time to time, the Company may be subject to various legal proceedings and claims related to matters arising in the ordinary course of business. The Company does not believe it is currently subject to any material matters where there is at least a reasonable possibility that a material loss may be incurred.

Income Taxes - Schedule of Cash Income Taxes Paid (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Line Items]
Federal	$ 213
State	17
Net cash paid during the year for income taxes	1,350	$ 3,179	$ 165
Ireland
Income Tax Disclosure [Line Items]
Income taxes, net of amounts refunded	72
United Kingdom
Income Tax Disclosure [Line Items]
Income taxes, net of amounts refunded	1,030
All other foreign
Income Tax Disclosure [Line Items]
Income taxes, net of amounts refunded	$ 18

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 3,669	$ 4,188	$ 7,462

Research, Collaboration and Licensing Agreements (Tables)

12 Months Ended

Dec. 31, 2025

License Agreements Research Collaborations And Development Agreements [Abstract]

Schedule of Revenue Recognized from Strategic Partnerships

Revenue recognized from the Company’s strategic partnerships is summarized as follows:


	Year ended December 31,
	2025		2024		2023
Jazz:
Milestone revenue	$	—	$	25,000	$	—
Development support payments	5,616		2,835		52,619
Drug supply for ongoing studies	6,548		19,228		25,662
Credit note for amendment of program	—		—		(20,100)
Other drug supply	2,103		15,464		13,350
Royalties	2,481		100		—

BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”):
Milestone revenue	20,000		8,000		—
Recognition of deferred revenue	18,334		—		—
Drug supply	762		3,009		1,080
Development support payments	—		—		537
Royalties	271		—		—

Johnson & Johnson Innovative Medicine (previously known as Janssen Biotech, Inc.) (“J&J”):
Milestone revenue	25,000		—		—

GlaxoSmithKline Intellectual Property Development Ltd. (“GSK”):
Milestone revenue	14,000		2,500		—

Bristol-Myers Squibb (“BMS”):
Option exercise fee	7,500		—		—

Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”):
Milestone revenue	3,100		—		—

Merck Sharp & Dohme LLC (“Merck”)
Research period extension fee	250		—		—

Research and development support and other payments	—		168		2,864
	$	105,965	$	76,304	$	76,012

Stockholders' Equity - Summary of Stock Options Granted (Details) $ / shares in Units, $ / shares in Units, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2025 CAD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2025 CAD ($) $ / shares shares	Dec. 31, 2024 CAD ($)	Dec. 31, 2023 CAD ($)
Number of Options
Granted (in shares)	0	0
Weighted- Average Contractual Term (years)
Weighted-average contractual term, vested and expected to vest	1 year 9 months 18 days	1 year 9 months 18 days
Canadian Dollar Under the New Option Stock Plan
Number of Options
Outstanding, beginning balance (in shares)	1,082,835	1,082,835	1,489,478	1,489,478
Granted (in shares)	0	0	0	0
Expired (in shares)	(28,707)	(28,707)	(58,902)	(58,902)
Exercised (in shares)	(444,397)	(444,397)	(224,042)	(224,042)
Forfeited (in shares)	(37,619)	(37,619)	(123,699)	(123,699)
Outstanding, ending balance (in shares)	572,112	572,112	1,082,835	1,082,835	1,489,478	1,489,478
Exercisable (in shares)	553,766						553,766
Vested and expected to vest (in shares)	570,277						570,277
Weighted- Average Exercise Price ($)
Beginning balance (in dollars per share) \| (per share)	$ 14.15	$ 20.36	$ 14.39	$ 19.59
Granted (in dollars per share) \| (per share)	0	0	0	0
Expired (in dollars per share) \| (per share)	28.75	39.94	23.46	32.37
Exercised (in dollars per share) \| (per share)	9.69	13.43	8.20	11.23
Forfeited (in dollars per share) \| (per share)	13.31	18.32	16.11	21.85
Ending balance (in dollars per share) \| (per share)	18.17	24.89	$ 14.15	$ 20.36	$ 14.39	$ 19.59
Exercisable (in dollars per share) \| (per share)	18.58	$ 25.45
Vested and expected to vest (in dollars per share) \| (per share)	$ 18.21						$ 24.95
Weighted- Average Contractual Term (years)
Weighted-average contractual term, outstanding	4 years 3 months 21 days	4 years 3 months 21 days	4 years 8 months 23 days	4 years 8 months 23 days	5 years 6 months	5 years 6 months
Weighted-average contractual term, exercisable	4 years 3 months	4 years 3 months
Weighted-average contractual term, vested and expected to vest	4 years 3 months 21 days	4 years 3 months 21 days
Aggregate intrinsic value ($)
Aggregate intrinsic value outstanding	$ 6,081		$ 4,509	$ 4,509	$ 2,255	$ 2,255	$ 8,327	$ 6,485	$ 2,987
Aggregate intrinsic value exercisable	5,701	$ 7,811
Aggregate intrinsic vested and expected to vest	$ 6,040						$ 8,276
U.S Dollar Under the New Option Stock Plan
Number of Options
Outstanding, beginning balance (in shares)	7,331,084	7,331,084	6,069,242	6,069,242
Granted (in shares)	2,467,225	2,467,225	3,135,500	3,135,500
Expired (in shares)	(63,994)	(63,994)	0	0
Exercised (in shares)	(1,298,292)	(1,298,292)	(735,864)	(735,864)
Forfeited (in shares)	(619,746)	(619,746)	(1,137,794)	(1,137,794)
Outstanding, ending balance (in shares)	7,816,277	7,816,277	7,331,084	7,331,084	6,069,242	6,069,242
Exercisable (in shares)	3,763,060						3,763,060
Vested and expected to vest (in shares)	7,078,461						7,078,461
Weighted- Average Exercise Price ($)
Beginning balance (in dollars per share) \| $ / shares	$ 12.01		$ 12.97
Granted (in dollars per share) \| $ / shares	14.21		11.15
Expired (in dollars per share) \| $ / shares	30.59		0
Exercised (in dollars per share) \| $ / shares	9.63		9.57
Forfeited (in dollars per share) \| $ / shares	14.99		16.34
Ending balance (in dollars per share) \| $ / shares	12.71		$ 12.01		$ 12.97
Exercisable (in dollars per share) \| $ / shares	12.78
Vested and expected to vest (in dollars per share) \| $ / shares	$ 12.68
Weighted- Average Contractual Term (years)
Weighted-average contractual term, outstanding	7 years 5 months 19 days	7 years 5 months 19 days	7 years 11 months 19 days	7 years 11 months 19 days	7 years 8 months 1 day	7 years 8 months 1 day
Weighted-average contractual term, exercisable	6 years 3 months 14 days	6 years 3 months 14 days
Weighted-average contractual term, vested and expected to vest	7 years 4 months 2 days	7 years 4 months 2 days
Aggregate intrinsic value ($)
Aggregate intrinsic value outstanding \| $	$ 109,157		$ 30,459	$ 30,459	$ 9,213	$ 9,213
Aggregate intrinsic value exercisable \| $	53,695
Aggregate intrinsic vested and expected to vest \| $	$ 99,302

Consolidated Statements of Loss and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenue:
Research and development collaborations (note 11)	$ 105,965	$ 76,304	$ 76,012
Operating expenses:
Research and development	137,000	134,621	143,619
General and administrative	61,514	61,506	70,446
Impairment on IPR&D (note 6)	0	17,287	0
Total operating expenses	198,514	213,414	214,065
Loss from operations	(92,549)	(137,110)	(138,053)
Other income:
Interest income	13,354	19,941	19,705
Other (expense) income, net (note 12)	(559)	558	(894)
Total other income, net	12,795	20,499	18,811
Loss before income taxes	(79,754)	(116,611)	(119,242)
Income tax (expense) recovery (note 13)	(1,376)	(6,084)	568
Net loss	(81,130)	(122,695)	(118,674)
Other comprehensive income (loss):
Unrealized income (loss) on available for sale securities, net of tax of nil (note 5)	873	(349)	56
Total other comprehensive income (loss)	873	(349)	56
Comprehensive loss	$ (80,257)	$ (123,044)	$ (118,618)
Net loss per common share (note 4):
Basic (in dollars per share)	$ (1.08)	$ (1.62)	$ (1.72)
Diluted (in dollars per share)	$ (1.08)	$ (1.62)	$ (1.72)
Weighted-average common stock outstanding (note 4):
Basic (in shares)	75,404,897	75,846,681	68,863,010
Diluted (in shares)	75,413,396	75,878,738	68,863,010

Business Segments - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Research and development collaborations (note 11)	$ 105,965	$ 76,304	$ 76,012
Total operating expenses	198,514	213,414	214,065
Segment loss	(92,549)	(137,110)	(138,053)
Change in contingent consideration	0	1,878	(630)
Impairment on IPR&D (note 6)	0	(17,287)	0
Interest income	13,354	19,941	19,705
Other (expense) income, net (note 12)	(559)	558	(894)
Income tax (expense) recovery, net	(1,376)	(6,084)	568
Net loss	(81,130)	(122,695)	(118,674)
Reportable Segment
Segment Reporting Information [Line Items]
Research and development collaborations (note 11)	105,965	76,304	76,012
Salaries and benefits	51,023	50,678	49,931
Other research and development expense	20,581	17,949	19,128
Other general and administrative expense	25,474	29,522	40,823
Total operating expenses	162,755	171,529	195,169
Segment loss	(56,790)	(95,225)	(119,157)
Depreciation and amortization	(7,725)	(8,684)	(10,164)
Stock-based compensation expense	(28,034)	(17,792)	(8,102)
Change in contingent consideration	0	1,878	(630)
Impairment on IPR&D (note 6)	0	(17,287)	0
Interest income	13,354	19,941	19,705
Other (expense) income, net (note 12)	(559)	558	(894)
Income tax (expense) recovery, net	(1,376)	(6,084)	568
Net loss	(81,130)	(122,695)	(118,674)
Reportable Segment \| Zanidatamab
Segment Reporting Information [Line Items]
Research and development expense	(1,828)	11,939	44,751
Reportable Segment \| ZW171
Segment Reporting Information [Line Items]
Research and development expense	9,672	7,151	10,686
Reportable Segment \| ZW191
Segment Reporting Information [Line Items]
Research and development expense	12,129	8,379	11,714
Reportable Segment \| ZW220
Segment Reporting Information [Line Items]
Research and development expense	2,922	13,824	1,585
Reportable Segment \| ZW251
Segment Reporting Information [Line Items]
Research and development expense	11,304	8,103	686
Reportable Segment \| Zanidatamab zovodotin
Segment Reporting Information [Line Items]
Research and development expense	364	6,595	8,046
Reportable Segment \| Expense for other preclinical and research programs
Segment Reporting Information [Line Items]
Research and development expense	$ 31,114	$ 17,389	$ 7,819

Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2025

Earnings Per Share [Abstract]

Schedule of Net (Loss) Income per Share

Net loss per share for the years ended December 31, 2025, 2024 and 2023 was as follows:


	Year Ended December 31,
	2025		2024		2023
Numerator:
Net loss attributable to common stockholders:
Basic	$	(81,130)	$	(122,695)	$	(118,674)
Adjustment for change in fair value of liability classified stock options	(196)		140		—
Diluted	$	(81,326)	$	(122,555)	$	(118,674)

Denominator:
Weighted-average common stock outstanding:
Basic	75,404,897		75,846,681		68,863,010
Adjustment for dilutive effect of liability classified stock options	8,499		32,057		—
Diluted	75,413,396		75,878,738		68,863,010

Net loss per common share – basic	$	(1.08)	$	(1.62)	$	(1.72)
Net loss per common share – diluted	$	(1.08)	$	(1.62)	$	(1.72)

Other Income (Expense), net (Tables)

12 Months Ended

Dec. 31, 2025

Other Income and Expenses [Abstract]

Schedule of Other Income (Expense) Nonoperating

Other income (expense), net consists of the following:


	Year ended December 31,
	2025		2024		2023
Foreign exchange (loss) gain	$	(610)	$	776	$	(1,185)
Other	51		(218)		291
	$	(559)	$	558	$	(894)

Commitment and Contingencies - Additional Information (Details) $ in Thousands, $ in Millions	Dec. 31, 2025 USD ($)	Dec. 31, 2025 CAD ($)	Dec. 31, 2024 USD ($)
Liability for Contingent Consideration
Other Commitments [Line Items]
Financial liabilities measured at fair value	$ 0		$ 0
Kairos Acquisition
Other Commitments [Line Items]
Contingent liability		$ 8.5
Kairos Acquisition \| First Phase 2 Trial
Other Commitments [Line Items]
Contingent liability		2.5
Kairos Acquisition \| First Phase 3 Trial
Other Commitments [Line Items]
Contingent liability		$ 6.0

- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

+ References + Details

Research, Collaboration and Licensing Agreements - Collaboration and License Agreement with Janssen Biotech, Inc. (Details)		12 Months Ended			98 Months Ended
	Nov. 13, 2017 USD ($) antibody	Dec. 31, 2025 USD ($) antibody	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2025 USD ($) antibody
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 105,965,000	$ 76,304,000	$ 76,012,000
Janssen Biotech, Inc. \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty term		10 years
Buy down payment		$ 10,000,000.0			$ 10,000,000.0
Janssen Biotech, Inc. \| Maximum \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody	6
Number of additional antibodies \| antibody	2
Number of antibody clinical trials initiated \| antibody	2	2			2
Number of antibody development deprioritized \| antibody		1			1
Number of remaining antibody clinical trials \| antibody		4			4
Janssen Biotech, Inc. \| License and Milestone Payments \| Maximum \| Eligible to Receive \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 1,450,000,000
Janssen Biotech, Inc. \| Upfront Fee \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)					$ 50,000,000.0
Janssen Biotech, Inc. \| Development Milestone \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 33,000,000.0
Janssen Biotech, Inc. \| Development Milestone \| Maximum \| Eligible to Receive \| Research Agreement Product One Member \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	61,000,000.0
Janssen Biotech, Inc. \| Bispecific Antibodies \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		8,000,000.0
Janssen Biotech, Inc. \| Metastatic Castration-Resistant Prostate Cancer \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 25,000,000.0
Janssen Biotech, Inc. \| Commercial Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)					$ 0
Janssen Biotech, Inc. \| Commercial Milestones \| Maximum \| Eligible to Receive \| Research Agreement Product Two \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	373,000,000.0
Janssen Biotech, Inc. \| Commercial Milestones \| Maximum \| Eligible to Receive \| Research Agreement Product Three \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	18,000,000.0
Janssen Biotech, Inc. \| Commercial Milestones \| Maximum \| Eligible to Receive \| Research Agreement Product Four \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 186,500,000

Summary of Significant Accounting Policies - Summary of Definite-lived Intangible Assets, Estimated Useful Lives (Details)	Dec. 31, 2025
Software
Finite-Lived Intangible Assets [Line Items]
Definite-lived intangible assets, useful life	3 years

- 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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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+ Details

Research, Collaboration and Licensing Agreements - Celgene Corporation and Celgene Alpine Investment Co. LLC (Details) $ in Thousands		1 Months Ended	12 Months Ended					120 Months Ended
	Dec. 23, 2014 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2025 USD ($) program option	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) program	Dec. 31, 2018 program	Dec. 31, 2017 program	Dec. 31, 2024 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)			$ 105,965	$ 76,304	$ 76,012
Celgene \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 8,000
Collaborative agreement expansion fee	4,000
Number of potential products to developed and commercialized \| program			2			10	8
Number of license options exercised \| option			2
Number of programs discontinued \| program					1
Celgene \| License Agreement \| Collaborative Arrangement \| Option Exercise Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)								$ 15,000
Celgene \| License Agreement \| Collaborative Arrangement \| Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	156,500		$ 313,000
Celgene \| License Agreement \| Collaborative Arrangement \| Maximum \| Eligible to Receive \| Development Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	101,500
Celgene \| License Agreement \| Collaborative Arrangement \| Maximum \| Eligible to Receive \| Commercial Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 55,000
Bristol-Myers Squibb (“BMS”): \| Upfront Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 12,000
Bristol-Myers Squibb (“BMS”): \| Option Exercise Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)			$ 7,500	$ 0	$ 0

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net loss	$ (81,130)	$ (122,695)	$ (118,674)
Items not involving cash:
Depreciation of property and equipment (note 7)	3,669	4,188	7,462
Amortization of intangible assets (note 8)	4,056	4,496	2,702
Stock-based compensation (note 10e)	28,034	17,792	8,102
Amortization and impairment of operating lease right-of-use assets	3,385	2,509	7,141
Impairment of acquired IPR&D (note 6)	0	17,287	0
Deferred income tax expense (recovery) (note 13)	945	691	(757)
Change in fair value of contingent consideration liability (note 15)	0	(1,878)	630
Change in fair value of investments in equity instruments	0	0	667
Unrealized foreign exchange loss (gain)	532	(1,481)	(31)
Changes in non-cash operating working capital:
Accounts receivable	51,200	(36,359)	13,922
Prepaid expenses and other current assets	6,509	(2,489)	4,295
Accounts payable and accrued liabilities	(23,648)	14,321	(44,789)
Operating lease liabilities	(3,342)	(8,313)	(3,663)
Deferred revenue and other consideration	(23,170)	3,555	3,699
Income taxes payable	(45)	(1,682)	970
Net cash used in operating activities	(33,005)	(110,058)	(118,324)
Cash flows from financing activities:
Proceeds from issuance of common stock under at-the-market program and from public offerings, net of issuance costs (notes 10a)	0	0	26,233
Private placement (note 10a)	4,988	0	49,862
Issuance of common stock on exercise of stock options (note 10e)	16,904	8,857	5,006
Issuance of common stock through employee stock purchase plan (note 10f)	1,425	930	820
Purchases of common stock for retirement (note 10c)	(41,695)	(30,051)	0
Deferred financing fees	(181)	(174)	(53)
Net cash (used in) / provided by financing activities	(18,559)	(20,438)	81,868
Cash flows from investing activities:
Purchases of marketable securities	(196,061)	(283,743)	(553,249)
Proceeds from marketable securities	225,076	325,565	350,073
Acquisition of property and equipment	(1,521)	(1,991)	(2,474)
Acquisition of intangible assets	(831)	(1,075)	(1,603)
Net cash provided by / (used in) investing activities	26,663	38,756	(207,253)
Effect of exchange rate changes on cash and cash equivalents	(45)	286	354
Net change in cash and cash equivalents	(24,946)	(91,454)	(243,355)
Cash and cash equivalents, beginning of year	66,103	157,557	400,912
Cash and cash equivalents, end of year	41,157	66,103	157,557
Supplemental cash flow information:
Net cash paid during the year for income taxes	1,350	3,179	165
Supplemental disclosure of non-cash investing and finance items:
Leased assets obtained in exchange for operating lease liabilities	2,443	644	1,900
Issuance of common stock upon exercise of pre-funded warrants (note 10d)	49,862	0	0
Purchases of common stock not settled	464	0	0
Acquisition of property and equipment and intangible assets in accounts payable and accrued liabilities	$ 0	$ 0	$ 122

Property and Equipment - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property and equipment	$ 36,378	$ 35,480
Less accumulated depreciation	(20,876)	(17,830)
Property and equipment, net	15,502	17,650
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment	3,233	2,815
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	1,850	2,408
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment	1,674	1,736
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment	13,838	13,331
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	15,243	15,190
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment	$ 540	$ 0

Stockholders' Equity

12 Months Ended

Dec. 31, 2025

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Stockholders’ Equity

a.Equity Offerings

2025 Private Placement

On August 10, 2025, the Company entered into a stock purchase agreement (the “Stock Purchase Agreement”) for a private placement with Mr. Gregory A. Ciongoli following his appointment as a director of the Company. Pursuant to the Stock Purchase Agreement, Mr. Ciongoli agreed to purchase 415,000 shares of common stock, $0.00001 par value per share, of the Company for an aggregate purchase price of $4,988.

2023 Private Placement

On December 28, 2023, the Company completed a private placement pursuant to which the Company sold 5,086,521 pre-funded warrants to purchase 5,086,521 shares of common stock at $9.8299 per pre-funded warrant. The Company received gross proceeds of $50,000 and net proceeds were $49,862, after expenses.

2023 ATM financing

On June 16, 2023, the Company sold 3,350,000 shares of common stock pursuant to the Company's at-the-market sale program, at $8.12 per common share. Net proceeds were $26,233 after underwriting commissions and offering expenses.

b.Authorized Share Capital and Preferred Stock

The Company’s authorized share capital consists of 1,000,000,000 shares of stock, consisting of (i) 900,000,000 shares of common stock, par value $0.00001 per share, and (ii) 100,000,000 shares of preferred stock, par value $0.00001 per share.

In connection with the Plan of Arrangement, the Company issued to Computershare Trust Company of Canada, a trust company existing under the laws of Canada (the “Share Trustee”), one share of the Company’s preferred stock, par value $0.00001 per share, which has certain variable voting rights in proportion to the number of Exchangeable Shares outstanding (the “Special Voting Preferred Stock”), enabling the Share Trustee to exercise voting rights for the benefit of the Exchangeable Shareholders.

Immediately prior to the completion of the Redomicile Transactions, there were 61,699,387 Zymeworks BC common shares issued and outstanding. In connection with the consummation of the Plan of Arrangement, 60,274,854 shares of Common Stock and 1,424,533 Exchangeable Shares were issued to former Zymeworks BC shareholders. As of December 31, 2025, there were 553,184 Exchangeable Shares held by former Zymeworks BC shareholders (December 31, 2024: 570,637). The Company will issue shares of its common stock as consideration when a holder of Exchangeable Shares calls for Exchangeable Shares to be retracted by ExchangeCo, when ExchangeCo redeems Exchangeable Shares from the holder, or when CallCo purchases Exchangeable Shares from the Exchangeable Shareholder under CallCo’s overriding call rights. These Exchangeable Shares and the Special Voting Preferred Stock, when taken together, are similar in substance to the Company’s common stock and are treated as such in calculation of basic net (loss) income per share.

c.Stock Repurchase Programs

2024 Repurchase Program

On August 1, 2024, the board of directors of the Company authorized a stock repurchase program (the “2024 Repurchase Program”), whereby the Company may repurchase up to $60,000 of the Company’s outstanding common stock, par value $0.00001 per share.

During the year ended December 31, 2024, the Company repurchased 2,545,402 shares of its common stock for a cost of $30,000, and incurred commission expense of $51, under the 2024 Repurchase Program, which have been recorded against accumulated deficit. The Company’s share repurchases in excess of issuances are subject to a 1% excise tax enacted by the Inflation Reduction Act of $152. During the year ended December 31, 2024, the Company retired all 2,545,402 shares repurchased. These shares were returned to the status of authorized and unissued shares.

During the year ended December 31, 2025, the Company completed the 2024 Repurchase Program by repurchasing 1,856,907 shares of its common stock for a cost of $29,997 and incurred commission expense of $37, which have been recorded against

accumulated deficit. Excise tax was estimated as nil. The Company retired all 1,856,907 shares repurchased. These shares were returned to the status of authorized and unissued shares.

The following table presents the Company’s 2024 Repurchase Program activity:


	Total number of shares purchased	Average price paid per share		Approximate value of shares purchased

Year Ended December 31, 2024	2,545,402	$	11.79	$	30,000
Year Ended December 31, 2025	1,856,907	$	16.15	$	29,997

2025 Repurchase Program

On November 16, 2025, the board of directors of the Company authorized a new stock repurchase program (the “2025 Repurchase Program”), whereby the Company may repurchase up to $125,000 of the Company’s outstanding common stock, par value $0.00001 per share.

During the year ended December 31, 2025, the Company repurchased 431,217 shares of its common stock for a cost of $11,188, incurred an obligation to purchase common stock for a cost of $464 which had not been settled by December 31, 2025, and incurred commission expense of $9, under the 2025 Repurchase Program, which have been recorded against accumulated deficit. Excise tax was estimated as nil. The Company retired all 431,217 shares repurchased. These shares were returned to the status of authorized and unissued shares.

The following table presents the Company’s 2025 Repurchase Program activity:


	Total number of shares purchased	Average price paid per share		Approximate value of shares purchased

Year Ended December 31, 2025	431,217	$	25.94	$	11,188

d.Pre-Funded Common Share Warrants

In connection with the public offerings completed on June 24, 2019, January 27, 2020, January 31, 2022 and private placement completed on December 28, 2023 (note 10a), the Company issued a total of 13,668,482 pre-funded warrants which granted holders of warrants the right to purchase up to 13,668,482 common shares or shares of the Company, at an exercise price of $0.0001 per share.

The pre-funded warrants are exercisable by the holders at any time on or after the original issue date. The pre-funded warrants do not expire unless they are exercised or settled in accordance with the pre-funded warrant agreement. As the pre-funded warrants meet the condition for equity classification, proceeds from issuance of the pre-funded warrants, net of any transaction costs, are recorded in additional paid-in capital. Upon exercise of the pre-funded warrants, the historical costs recorded in additional paid-in capital along with exercise price collected from holders will be recorded in common shares. As the amounts required to exercise the warrants are nominal, these instruments are considered in the calculation of basic net (loss) income per share.

On August 23, 2022, October 25, 2022, October 27, 2022 and October 19, 2023, a total of 8,581,961 pre-funded warrants were exercised in exchange for issuance of 8,581,868 common shares.

On June 26, 2025, 5,086,521 pre-funded warrants were exercised in full in exchange for 5,086,480 shares of common stock by EcoR1, which is a related party due to its beneficial ownership of the Company’s outstanding shares of common stock, and as of December 31, 2025 there were no pre-funded warrants outstanding (December 31, 2024: 5,086,521).

e.Stock-Based Compensation

In connection with Redomicile Transactions in 2022, Zymeworks BC. assigned to the Company, and the Company assumed, all of Zymeworks BC’s rights and obligations under each of the stock-based compensation plans, as described below, and such plans became the Company’s stock-based compensation plans, with each outstanding award assumed by the Company and

deemed exchanged for equivalent awards of the Company, except that the security issuable upon exercise or settlement, as applicable, will be shares of common stock of the Company rather than common shares of Zymeworks BC.

Original Stock Option Plan

On July 14, 2006, the shareholders of the Company approved an employee stock option plan (the “Original Plan”). The total number of options outstanding is not to exceed 20% of the issued common shares of the Company. Options granted under the Original Plan are exercisable at various dates over their 10-year life. The exercise prices of the Company’s stock options under the Original Plan are denominated in Canadian dollars. Upon the effectiveness of the Company’s New Plan described below, no further options were issuable under the Original Plan. However, all outstanding options granted under the Original Plan remain outstanding, subject to the terms of the Original Plan and the applicable grant documents, until such outstanding options are exercised or they terminate or expire by their terms.

New Plan and Inducement Plan

On April 10, 2017, the Company’s shareholders approved a new stock option plan, which became effective immediately prior to the consummation of the Company’s initial public offering (“IPO”). This plan allows for the grant of options, and also permitted the Company to grant incentive stock options (“ISOs”), within the meaning of Section 422 of the Internal Revenue Code, to its employees, until the shares reserved for issuance of ISOs were depleted. On June 7, 2018, the Company’s shareholders approved an amendment and restatement of this plan (this plan, as amended and restated, the “New Plan”), which includes an article that allows the Company to grant restricted shares, RSU and other share-based awards, in addition to stock options. As of December 31, 2025, 5,023,809 shares of common stock were available for future award grants under the New Plan (December 31, 2024: 5,196,630 shares of common stock).

On January 5, 2022, the board of directors approved the Zymeworks Inc. Inducement Stock Option and Equity Compensation Plan (the “Inducement Plan”) and reserved 750,000 of the Company’s common shares for issuance pursuant to equity awards granted thereunder. On July 19, 2024, the board of directors approved an amendment and restatement of the Inducement Plan, which increased the number of shares of the Company’s common stock available for future issuance pursuant to equity awards granted under the Inducement Plan by 700,000 shares. As a result of this increase, a total of 1,450,000 shares will have been available for issuance pursuant to equity awards granted under the Inducement Plan since the inception of the Inducement Plan in January 2022. As of December 31, 2025, 390,000 shares of common stock were available for future award grants under this plan (December 31, 2024: 390,000).

RSUs

The following table summarizes the Company’s RSU activity under the New Plan:


	Number of RSUs	Weighted- average grant date fair value ($)
Outstanding, December 31, 2023	771,413	8.63
Granted	957,750	10.56
Vested and settled	(225,004)	8.76
Forfeited	(210,189)	10.75
Outstanding, December 31, 2024	1,293,970	9.69
Granted	1,398,697	14.29
Vested and settled	(560,620)	9.40
Forfeited	(184,463)	11.59
Outstanding, December 31, 2025	1,947,584	12.90

As of December 31, 2025, there was $7,512 of unamortized RSU expense that will be recognized over a weighted average period of 1.52 years.

Stock Options

The following table summarizes the Company’s stock options granted in Canadian dollars under the Original Plan and the New Plan:


	Number of Options	Weighted- Average Exercise Price (C$)	Weighted- Average Exercise Price ($)	Weighted- Average Contractual Term (years)	Aggregate intrinsic value (C$)	Aggregate intrinsic value ($)
Outstanding, December 31, 2023	1,489,478	19.59	14.39	5.50	2,987	2,255
Granted	—	—	—
Expired	(58,902)	32.37	23.46
Exercised	(224,042)	11.23	8.20
Forfeited	(123,699)	21.85	16.11
Outstanding, December 31, 2024	1,082,835	20.36	14.15	4.73	6,485	4,509
Granted	—	—	—
Expired	(28,707)	39.94	28.75
Exercised	(444,397)	13.43	9.69
Forfeited	(37,619)	18.32	13.31
Outstanding, December 31, 2025	572,112	24.89	18.17	4.31	8,327	6,081
December 31, 2025
Exercisable	553,766	25.45	18.58	4.25	7,811	5,701
Vested and expected to vest	570,277	24.95	18.21	4.31	8,276	6,040

The following table summarizes the Company’s stock options granted in U.S. dollars under the New Plan and the Inducement Plan:


	Number of Options	Weighted- Average Exercise Price ($)	Weighted- Average Contractual Term (years)	Aggregate intrinsic value ($)
Outstanding, December 31, 2023	6,069,242	12.97	7.67	9,213
Granted	3,135,500	11.15
Expired	—	—
Exercised	(735,864)	9.57
Forfeited	(1,137,794)	16.34
Outstanding, December 31, 2024	7,331,084	12.01	7.97	30,459
Granted	2,467,225	14.21
Expired	(63,994)	30.59
Exercised	(1,298,292)	9.63
Forfeited	(619,746)	14.99
Outstanding, December 31, 2025	7,816,277	12.71	7.47	109,157
December 31, 2025
Exercisable	3,763,060	12.78	6.29	53,695
Vested and expected to vest	7,078,461	12.68	7.34	99,302

During the year ended December 31, 2025, the Company received cash proceeds of $16,904 (2024: $8,857 and 2023: $5,006) from stock options exercised. The stock options outstanding at December 31, 2025 expire at various dates from November 9, 2026 to December 9, 2035.

A summary of the non-vested stock option activity and related information of the Company’s stock options granted in Canadian dollars is as follows:


	Number of options	Weighted-average grant date fair value (C$)	Weighted- average grant date fair value (US$)
Non-vested, December 31, 2024	100,967	7.31	5.08
Options granted	—	—	—
Options vested	(72,760)	8.02	5.85
Options forfeited and cancelled	(9,861)	5.64	4.12
Non-vested, December 31, 2025	18,346	5.42	3.95

A summary of the non-vested stock option activity and related information of the Company’s stock options granted in U.S. dollars is as follows:


	Number of options	Weighted- average grant date fair value (US$)
Non-vested, December 31, 2024	4,147,288	6.65
Options granted	2,467,225	8.76
Options vested	(2,086,563)	6.72
Options forfeited and cancelled	(474,733)	6.36
Non-vested, December 31, 2025	4,053,217	7.84

The estimated fair values of options granted to officers, directors, employees and consultants are amortized over the relevant vesting periods. Stock-based compensation expense for equity classified instruments, as well as the financial statement impact of the amortization and periodic revaluation of liability classified instruments (note 2), are recorded in research and development expense and general and administration expense as follows:


	Year Ended December 31,
	2025		2024		2023

Research and development expense	$	12,849	$	8,382	$	2,404
General and administrative expense	$	14,687	$	9,041	$	5,316

Amounts for equity classified instruments above include stock-based compensation expense relating to RSUs of $10,727 for the year ended December 31, 2025 (2024: $5,813 and 2023: $3,369).

For the year ended December 31, 2025, stock-based compensation expense of $27,069 was recorded in additional paid-in capital and $887 was recorded in the liability classified stock options and ESPP liability accounts (2024: $16,716 in additional paid-in capital and recovery of $211 in liability classified stock options and ESPP liability accounts, 2023: $8,196 in additional paid-in capital and recovery of $630 in liability classified stock options and ESPP liability accounts).

The estimated fair value of stock options granted under the New Plan was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Year ended December 31,
	2025		2024		2023
Dividend yield	0	%	0	%	0	%
Expected volatility	63.1	%	64.5	%	68.1	%
Risk-free interest rate	4.32	%	4.04	%	3.94	%
Expected average life of options	6.05 years		6.00 years		5.89 years

Expected Volatility — Volatility is a measure of the amount by which a financial variable such as a share price has fluctuated (historical volatility) or is expected to fluctuate (expected volatility) during a period. The Company has calculated the expected volatility using the volatility of its own stock.

Risk-Free Interest Rate — This rate is from the Government of Canada and U.S. Federal Reserve marketable bonds for the month prior to each option grant during the year, having a term that most closely resembles the expected life of the option.

Expected Term — This is the period of time that the options granted are expected to remain unexercised. Options granted have a maximum term of ten years. The Company uses the simplified method to calculate the average expected term, which represents the average of the vesting period and the contractual term.

The weighted-average Black-Scholes option pricing assumptions for liability classified stock options outstanding at December 31, 2025 and 2024 are as follows:


	December 31, 2025		December 31, 2024
Dividend yield	0	%	0	%
Expected volatility	55.3	%	45.8	%
Risk-free interest rate	2.56	%	2.90	%
Expected average option term	0.90 years		0.85 years
Number of liability classified stock options outstanding	64,402		272,330

The total intrinsic value of stock options exercised during the years ended December 31, 2025, 2024 and 2023 was $14,152, $2,242 and $758 respectively. At December 31, 2025, the unamortized compensation expense related to unvested options was $13,051. The remaining unamortized compensation expense as of December 31, 2025 will be recognized over a weighted-average period of 1.8 years.

f.Employee Stock Purchase Plan (“ESPP”)

The ESPP, as amended, allows eligible employees to acquire common shares at a discounted purchase price of the lesser of (i) 85% of the market price of a common share on the first day of the applicable purchase period and (ii) 85% of the market price of a common share on the purchase date. The ESPP qualifies as an “employee stock purchase plan” within the meaning of Section 423 of the Code for employees who are U.S. taxpayers.

As this plan is considered compensatory, the Company recognizes compensation expense on these awards based on their estimated grant date fair value using the Black-Scholes option pricing model. The Company recognizes compensation expense in the consolidated statements of (loss) income and comprehensive (loss) income on a straight-line basis over the requisite service period. For the year ended December 31, 2025, the Company recorded compensation expense of $498 (2024: $370, 2023: $387) in research and development expense and general and administrative expense accounts. As of December 31, 2025, the total amount contributed by ESPP participants and not yet settled is $670 (December 31, 2024: $577).

- Definition

The entire disclosure for equity.

+ 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 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Common stock, par value per share (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	900,000,000	900,000,000
Common shares, issued (in shares)	74,638,413	68,964,319
Common shares, outstanding (in shares)	74,638,413	68,964,319
Preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares issued (in shares)	1	1
Preferred stock, shares outstanding (in shares)	1	1
Exchangeable stock, shares issued (in shares)	553,184	570,637
Exchangeable shares, shares outstanding (in shares)	553,184	570,637

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2025

Property, Plant and Equipment [Abstract]

Schedule of Components of Property and Equipment

Property and equipment consist of the following:


	December 31,
	2025		2024
Computer hardware	$	3,233	$	2,815
Furniture and fixtures	1,850		2,408
Office equipment	1,674		1,736
Laboratory equipment	13,838		13,331
Leasehold improvements	15,243		15,190
Construction in progress	540		—
Property and equipment	$	36,378	$	35,480
Less accumulated depreciation	(20,876)		(17,830)
Property and equipment, net	$	15,502	$	17,650

IPR&D and Goodwill

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

IPR&D and Goodwill

Acquired IPR&D

In-process research and development assets (“IPR&D”) acquired in the 2016 Kairos Therapeutics Inc. (“Kairos”) business combination were classified as indefinite-lived intangible assets and were not amortized until their classification as definite-lived assets. During the year ended December 31, 2024, the Company determined that the fair value of IPR&D, which was estimated using an income approach, was less than its carrying value. Accordingly, the Company recorded an impairment charge of $17,287. The impairment was a result of the Company's decision to discontinue the zanidatamab zovodotin clinical development program which utilized the acquired technology represented by the IPR&D assets. As of July 1, 2024, the Company classified the remaining assets as definite-lived and commenced amortization, which was fully amortized as of December 31, 2024.

The following table summarizes the carrying value of IPR&D, net of impairment:


	Acquired IPR&D		Accumulated Impairment		Accumulated Amortization		Net
Balance at December 31, 2022	$	20,700	$	(3,072)	$	—	$	17,628
Change during the period	—		—		—		—
Balance at December 31, 2023	$	20,700	$	(3,072)	$	—	$	17,628
Change during the period	—		(17,287)		(341)		(17,628)
Balance at December 31, 2024	$	20,700	$	(20,359)	$	(341)	$	—

Goodwill

The Company performed its annual impairment test of goodwill as of December 31, 2025 and concluded that no impairment existed. As part of the evaluation of the recoverability of goodwill, the Company identified only one reporting unit to which the total carrying amount of goodwill has been assigned. As at December 31, 2025, the Company performed a qualitative assessment for its annual impairment test of goodwill after concluding that it was not more likely than not that the fair value of the reporting unit was less than its carrying value. Consequently, a quantitative impairment test was not required.

Liabilities

12 Months Ended

Dec. 31, 2025

Payables and Accruals [Abstract]

Liabilities

Accounts payable and accrued liabilities consisted of the following:


	December 31,
	2025		2024
Trade payables	$	4,403	$	3,903
Accrued research and development expenses	19,225		43,114
Goods and services tax payable	425		1,250
Employee compensation and related accruals	8,828		6,222
Fair value of liability classified stock options	844		1,264
Accrued legal, professional fees and other	2,621		4,085
Total	$	36,346	$	59,838

Other long-term liabilities consisted of the following:


	December 31,
	2025		2024
Liability from in-licensing agreements	$	278	$	447
Finance lease liability (note 14)	—		28
Other	—		448
Total	$	278	$	923

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Basis of Presentation

Foreign Currency

Use of Estimates

Revenue Recognition

•non-refundable, upfront license and platform technology access fees;

•research, development and regulatory milestone payments;

•research support, development and other payments; and

•royalties and commercial milestone payments.

Non-refundable, upfront license and platform technology access fees

Research, development and regulatory milestone payments

Research and development milestones in the Company’s collaboration agreements may include some, but not necessarily all, of the following types of events:

• completion of preclinical research and development work leading to selection of product candidates;

• initiation of Phase 1, Phase 2 and Phase 3 clinical trials; and

• achievement of certain other technical, scientific or development criteria.

Regulatory milestone payments may include the following types of events:

• marketing approval in major markets, such as the United States, Europe, Japan or China.

Research support, development and other payments

Supply of clinical trial drugs and comparator drugs

Royalties and commercial milestone payments

Contract assets and liabilities

Modifications of contracts with customers

Cash Equivalents

Investments

Marketable Securities

Accounts Receivable and Expected Credit Losses

Financial Instruments

Fair Value Measurements

The Company measures certain financial instruments and other items at fair value.

• Level 1 inputs are unadjusted quoted market prices for identical instruments available in active markets.

• Level 3 inputs are unobservable inputs for the asset or liability and will reflect management’s assessment about market assumptions that would be used to price the asset or liability.

Foreign Currency Risk

Concentration of Credit Risk

Liquidity Risk

Segment Information

Property and Equipment

The Company records depreciation using the straight-line method over the estimated useful lives of the property and equipment as follows:


Asset Class						Rate
Computer hardware						3 years
Office equipment						3 years
Furniture and fixtures						5 years
Laboratory equipment						7 years
Leasehold improvements						Shorter of the lease term or useful life

Property and equipment acquired or disposed of during the year are depreciated proportionately for the period they are in use.

Leases

Patents and Intellectual Property Costs

Government Grants and Credits

Research and Development Costs

Clinical Trial Expense Accruals

Income Taxes

litigation or appeal. For those positions that meet the recognition criteria, they are measured as the largest amount that is more than 50% likely to be realized upon ultimate settlement.

Stock-Based Compensation

Stock Repurchases

Business Combination and Goodwill

Business Combinations and Goodwill

Acquired In-Process Research and Development (IPR&D) and Definite-lived Intangible Assets

The Company records amortization using the straight-line method over the estimated useful lives of the definite-lived intangible assets as follows:


Asset Class						Rate
Software						3 years
Licensing agreements						Shorter of the licensing term or useful life

Net income (loss) per share

Recent accounting pronouncements adopted and Recent accounting pronouncements not yet adopted

Recent accounting pronouncements adopted

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments require disclosure of specific categories in the rate reconciliation and provide additional information for reconciling items that meet a quantitative threshold and further disaggregation of income taxes paid for individually significant jurisdictions. The ASU is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The standard is to be applied on a prospective basis, with the option for retrospective application. The Company has adopted this accounting pronouncement on the accompanying financial statements prospectively to the current annual period. Prior period disclosures have not been adjusted to reflect the new disclosure requirements. See note 13 Income Taxes in the accompanying notes to the consolidated financial statements for further detail.

Recent accounting pronouncements not yet adopted

In November 2024, the FASB issued ASU 2024-03, Income Statement Reporting – Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40), Disaggregation of Income Statement Expenses. The standard update improves the disclosures about a public business entity’s expenses by requiring more detailed information about the types of expenses (including purchases of inventory, employee compensation, depreciation and amortization) included within income statement expense captions. The guidance will be effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The standard updates are to be applied prospectively with the option for retrospective application. The Company is currently evaluating the impact of adoption of the standard update on its consolidated financial statements.

Other Income (Expense), net -Schedule Of Other Non operating Income Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Other Income and Expenses [Abstract]
Foreign exchange (loss) gain	$ (610)	$ 776	$ (1,185)
Other	51	(218)	291
Total other income, net	$ (559)	$ 558	$ (894)

Subsequent event	12 Months Ended
Subsequent event	Dec. 31, 2025
Subsequent Events [Abstract]
Subsequent event	Subsequent event On March 2, 2026, Zymeworks BC entered into a sale agreement (the “Sale Agreement”) with Zymeworks Royalty Limited Partnership (the “Subsidiary”) a special purpose entity newly formed by Zymeworks BC and by its general partner Zymeworks General Partner ULC (“Zymeworks GP”). Under the Sale Agreement, Zymeworks BC sold to the Subsidiary a 30% interest in future royalties from the license agreements with Jazz Pharmaceuticals Ireland Limited (“Jazz”) and BeOne Medicines Ltd. (“BeOne”) relating to Ziihera (zanidatamab‑hrii), not to exceed 120% of the maximum amount payable (excluding indemnification and other similar obligations) by the Subsidiary under the Loan Agreement (defined below) (such 30% interest, the “Transferred Royalty Interest”). Following the transfer, the Subsidiary entered into a loan agreement (the “Loan Agreement”) with Royalty Pharma Development Funding, LLC (“Royalty Pharma”), acting as administrative agent and lender, pursuant to which the Subsidiary borrowed $250.0 million in a non‑recourse, secured term loan (the “Loan”). The loan bears fixed interest and matures on December 31, 2042. Under the terms of the Loan Agreement, the amount payable to Royalty Pharma no later than the Maturity Date is approximately $481.3 million, provided that if the Loan is repaid in full on or before December 31, 2033, the amount payable to the Lenders is $412.5 million, in each case inclusive of all applicable interest, yield protection premiums, early redemption fees, exit fees and other amounts payable under the Loan Agreement (excluding indemnification and similar obligations). Amounts repaid may not be reborrowed. The Loan Agreement is fully non‑recourse to Zymeworks BC and Zymeworks Inc. and is secured solely by the Subsidiary’s assets, including the Transferred Royalty Interest, related rights under the Sale Agreement, and the deposit account used to receive royalty payments. The Sale Agreement and Loan Agreement contain customary covenants and restrictions, including certain transfers, additional indebtedness, and related matters. In the event of certain defaults, such as termination of either Covered Agreement, specified breaches, or a change of control of the Company, Royalty Pharma may declare all outstanding principal, accrued interest, and applicable fees immediately due and enforce its rights against the collateral securing the loan.

Leases - Additional Information (Details) $ in Thousands	12 Months Ended
Leases - Additional Information (Details) $ in Thousands	Dec. 31, 2025 USD ($) renewalOption	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Apr. 04, 2024 USD ($)
Lessee, Lease, Description [Line Items]
Future operating lease payments	$ 22,964
Cash paid for measurement of operating lease liabilities	4,270	$ 4,152
Impairment loss	$ 316		$ 0	$ 0
Building
Lessee, Lease, Description [Line Items]
Termination fee					$ 6,075
British Columbia \| Building
Lessee, Lease, Description [Line Items]
Number of renewal options \| renewalOption	2
Renewal term	5 years

IPR&D and Goodwill - Additional Information (Details)	12 Months Ended
IPR&D and Goodwill - Additional Information (Details)	Dec. 31, 2025 USD ($) unit	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment on acquired IPR&D	$ 0	$ 17,287,000	$ 0
Goodwill, impairment loss	$ 0
Number of reporting units \| unit	1

- Definition

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References + Details

Commitment and Contingencies (Tables)

12 Months Ended

Dec. 31, 2025

Commitments and Contingencies Disclosure [Abstract]

Schedule of Changes in Fair Value of the Company's Liability for Contingent Consideration

The following table presents the changes in fair value of the Company’s liability for contingent consideration:


	Liability at the beginning of the period		Increase (decrease) in fair value of liability for contingent consideration	Amounts paid or transferred to payables	Liability at end of the period
Year ended December 31, 2025	$	—	—	—	$	—
Year ended December 31, 2024	$	1,878	(1,878)	—	$	—

Liabilities (Tables)

12 Months Ended

Dec. 31, 2025

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consisted of the following:


	December 31,
	2025		2024
Trade payables	$	4,403	$	3,903
Accrued research and development expenses	19,225		43,114
Goods and services tax payable	425		1,250
Employee compensation and related accruals	8,828		6,222
Fair value of liability classified stock options	844		1,264
Accrued legal, professional fees and other	2,621		4,085
Total	$	36,346	$	59,838

Schedule of Other Long-Term Liabilities

Other long-term liabilities consisted of the following:


	December 31,
	2025		2024
Liability from in-licensing agreements	$	278	$	447
Finance lease liability (note 14)	—		28
Other	—		448
Total	$	278	$	923

Subsequent event (Details) - Subsequent Event $ in Millions	Mar. 02, 2026 USD ($)
Zymeworks Royalty Limited Partnership
Subsequent Event [Line Items]
Future royalty percentage sold	30.00%
Future royalty percentage not to exceed threshold percentage of loan payable	120.00%
Zymeworks Royalty Limited Partnership \| Jazz: \| License And Collaboration Agreement \| Collaborative Arrangement
Subsequent Event [Line Items]
Future royalty percentage sold	30.00%
Zymeworks Royalty Limited Partnership \| BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Research and License Agreement \| Collaborative Arrangement
Subsequent Event [Line Items]
Future royalty percentage sold	30.00%
Royalty Pharma \| Zymeworks Royalty Limited Partnership \| Secured Debt \| Non-Recourse Secured Term Loan
Subsequent Event [Line Items]
Face amount	$ 250.0
Royalty Pharma \| Zymeworks Royalty Limited Partnership \| Secured Debt \| Non-Recourse Secured Term Loan \| Amount Due If Paid At Maturity
Subsequent Event [Line Items]
Long-term Debt	481.3
Royalty Pharma \| Zymeworks Royalty Limited Partnership \| Secured Debt \| Non-Recourse Secured Term Loan \| Amount Due If Paid On Or Before December 31, 2033
Subsequent Event [Line Items]
Long-term Debt	$ 412.5

Cash, Cash Equivalents and Marketable Securities - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	$ 41,157	$ 66,103
Marketable securities:	229,427	258,101
Assets measured at fair value	270,584	324,204
GICs and mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	21,920	37,166
U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	41,299	86,553
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	166,208	134,382
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	32,189	31,483
Marketable securities:	63,219	123,719
Assets measured at fair value	95,408	155,202
Level 1 \| GICs and mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	21,920	37,166
Level 1 \| U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	41,299	86,553
Level 1 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	0
Marketable securities:	166,208	134,382
Assets measured at fair value	166,208	134,382
Level 2 \| GICs and mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Level 2 \| U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Level 2 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	166,208	134,382
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	0
Marketable securities:	0	0
Assets measured at fair value	0	0
Level 3 \| GICs and mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Level 3 \| U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Level 3 \| Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	8,968	34,620
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	32,189	16,398
Money market funds \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	32,189	16,398
Money market funds \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	0
Money market funds \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	0
GICs and mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	15,085
GICs and mutual funds \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	15,085
GICs and mutual funds \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	0	0
GICs and mutual funds \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	$ 0	$ 0

Award Timing Disclosure	12 Months Ended
Award Timing Disclosure	Dec. 31, 2025
Award Timing Disclosures [Line Items]
Award Timing MNPI Disclosure	During 2025, we granted stock options to employees, including our named executive officers. We do not take material nonpublic information into account in determining the timing of such awards. Further, we have not timed the disclosure of material nonpublic information for the purpose of affecting the value of executive compensation. We typically grant annual equity awards (including stock options) to our executive officers and non-executive employees early in the first quarter of each year. For equity awards to executive officers in connection with their hire date, such grants are typically made on the date of the commencement of their employment. For equity awards to non-executive employees in connection with their hire date, such grants are typically made on a pre-determined date in the month following the commencement of their employment. We have never granted stock appreciation rights to any employees or other service providers.
Award Timing Predetermined	false
Award Timing, How MNPI Considered	We do not take material nonpublic information into account in determining the timing of such awards. Further, we have not timed the disclosure of material nonpublic information for the purpose of affecting the value of executive compensation. We typically grant annual equity awards (including stock options) to our executive officers and non-executive employees early in the first quarter of each year. For equity awards to executive officers in connection with their hire date, such grants are typically made on the date of the commencement of their employment. For equity awards to non-executive employees in connection with their hire date, such grants are typically made on a pre-determined date in the month following the commencement of their employment. We have never granted stock appreciation rights to any employees or other service providers.
MNPI Disclosure Timed for Compensation Value	false

Income Taxes - Schedule of Loss Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
United States	$ (16,809)
Foreign	(62,945)
Loss before income taxes	$ (79,754)	$ (116,611)	$ (119,242)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

Net Loss per Share - Schedule of Calculation of Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Numerator:
Basic	$ (81,130)	$ (122,695)	$ (118,674)
Adjustment for change in fair value of liability classified stock options	(196)	140	0
Diluted	$ (81,326)	$ (122,555)	$ (118,674)
Weighted-average common stock outstanding:
Basic (in shares)	75,404,897	75,846,681	68,863,010
Adjustment for dilutive effect of liability classified stock options (in shares)	8,499	32,057	0
Diluted (in shares)	75,413,396	75,878,738	68,863,010
Net loss per common share – basic (in dollars per share)	$ (1.08)	$ (1.62)	$ (1.72)
Net loss per common share – diluted (in dollars per share)	$ (1.08)	$ (1.62)	$ (1.72)

Research, Collaboration and Licensing Agreements - Research and License Agreement with LEO Pharma A/S (Details)	12 Months Ended				86 Months Ended
	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2025 USD ($)	Oct. 23, 2018 antibody
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 105,965,000	$ 76,304,000	$ 76,012,000
LEO Pharma \| Research and License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody						2
LEO Pharma \| Upfront Fee \| Research and License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				$ 5,000,000.0
LEO Pharma \| Commercial and Development Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)					$ 0

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Our cybersecurity risk management strategy focuses on several areas: •Identification and Escalation: We have implemented a cross-functional approach to assessing, identifying and managing cybersecurity threats and incidents. Our program includes controls and procedures to identify, classify and escalate certain cybersecurity incidents to provide management visibility and obtain direction from management. •Technical Safeguards: We implement technical safeguards that are designed to protect our information systems from cybersecurity threats, which are evaluated and improved through vulnerability assessments and cybersecurity threat intelligence, as well as outside audits. •Incident Response and Recovery Planning: We have established and maintain an incident response plan and a business continuity and disaster recovery plan designed to address our response to a cybersecurity incident. •Third-Party Risk Management: We use a risk‑based approach to identify, assess, and oversee cybersecurity threats associated with third parties, including vendors, service providers, external system users, and other organizations whose systems could impact our business. This oversight also includes outside auditors and consultants who may access or advise on our cybersecurity systems. •Education and Awareness: We provide regular, mandatory training for all employees regarding cybersecurity threats as a means to equip our employees with tools to make employees aware of and to address cybersecurity threats, and to communicate our evolving information security policies, standards, processes, and practices.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	Our board of directors is responsible for overseeing our risk management program, and cybersecurity is a critical element that has been integrated into our overall risk management program.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Our board of directors, in coordination with the audit committee of our board of directors, oversees our risk management program, including the management of cybersecurity threats. Our board of directors and our audit committee receive prompt and timely information regarding cybersecurity risks, as well as ongoing updates regarding any such risk, from senior management.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	Our board of directors, in coordination with the audit committee of our board of directors, oversees our risk management program, including the management of cybersecurity threats. Our board of directors and our audit committee receive prompt and timely information regarding cybersecurity risks, as well as ongoing updates regarding any such risk, from senior management.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Our board of directors and our audit committee receive prompt and timely information regarding cybersecurity risks, as well as ongoing updates regarding any such risk, from senior management.
Cybersecurity Risk Role of Management [Text Block]	Our Director of Information Technology, who has over 18 years’ experience with cybersecurity at public and private companies, in coordination with senior management, works collaboratively across our company to implement a program designed to protect our information systems from cybersecurity threats and to promptly respond to cybersecurity incidents in accordance with our incident response and recovery plans. To facilitate the success of our cybersecurity program, a cross-functional team throughout our company addresses cybersecurity threats and responds to cybersecurity incidents. Through ongoing communications with this team, the Director of Information Technology and senior management are informed about and monitor the prevention, detection, mitigation and remediation of cybersecurity threats and incidents in real time and report such threats and incidents to the Audit Committee when appropriate.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Our Director of Information Technology, who has over 18 years’ experience with cybersecurity at public and private companies, in coordination with senior management, works collaboratively across our company to implement a program designed to protect our information systems from cybersecurity threats and to promptly respond to cybersecurity incidents in accordance with our incident response and recovery plans.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Our Director of Information Technology, who has over 18 years’ experience with cybersecurity at public and private companies, in coordination with senior management, works collaboratively across our company to implement a program designed to protect our information systems from cybersecurity threats and to promptly respond to cybersecurity incidents in accordance with our incident response and recovery plans.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Our Director of Information Technology, who has over 18 years’ experience with cybersecurity at public and private companies, in coordination with senior management, works collaboratively across our company to implement a program designed to protect our information systems from cybersecurity threats and to promptly respond to cybersecurity incidents in accordance with our incident response and recovery plans. To facilitate the success of our cybersecurity program, a cross-functional team throughout our company addresses cybersecurity threats and responds to cybersecurity incidents. Through ongoing communications with this team, the Director of Information Technology and senior management are informed about and monitor the prevention, detection, mitigation and remediation of cybersecurity threats and incidents in real time and report such threats and incidents to the Audit Committee when appropriate.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Stockholders' Equity - Schedule of RSUs Outstanding (Details) - Restricted Stock Units (RSUs) - $ / shares	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Number of RSUs
Outstanding at beginning of period (in shares)	1,293,970	771,413
Granted (in shares)	1,398,697	957,750
Vested and settled (in shares)	(560,620)	(225,004)
Forfeited (in shares)	(184,463)	(210,189)
Outstanding, at end of period (in shares)	1,947,584	1,293,970
Weighted- average grant date fair value ($)
Outstanding, at beginning of period (in dollars per shares)	$ 9.69	$ 8.63
Granted (in dollars per share)	14.29	10.56
Vested and settled (in dollars per share)	9.40	8.76
Forfeited (in dollars per share)	11.59	10.75
Outstanding, at end of period (in dollars per shares)	$ 12.90	$ 9.69

Income Taxes - Schedule of Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Unrecognized Tax Benefits [Roll Forward]
Balance, beginning of year	$ 3,115	$ 3,077	$ 3,063
Gross increases related to prior year tax positions	2,364	0	0
Gross decreases to tax positions in prior periods	0	0	0
Gross increases to current period tax positions	97	38	14
Gross decreases due to settlements with taxing authorities	0	0	0
Gross decreases due to statute of limitations lapse	0	0	0
Balance, end of year	$ 5,576	$ 3,115	$ 3,077

Income Taxes - Schedule of Significant Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Deferred tax assets:
Non-capital losses carried forward	$ 199,946	$ 177,660
Deferred revenue	4,596	10,852
Share issuance costs	666	1,360
Property and equipment	0	71
Intangible assets	5,271	4,539
Research and development deductions and credits	57,097	50,415
Stock options	7,724	8,388
Operating lease liability	4,657	4,761
Other	42	202
Gross deferred tax assets	279,999	258,248
Deferred tax liabilities:
Property and equipment	(243)	(174)
Operating lease right-of-use assets	(4,024)	(4,294)
Outside basis difference in foreign subsidiary	(2,414)	(2,429)
Stock options	0	(2,333)
Other	(182)	(176)
Gross deferred tax liabilities	(6,863)	(9,406)
Deferred tax assets liabilities before valuation allowance	273,136	248,842
Less: valuation allowance	(274,457)	(249,218)
Net deferred tax (liabilities) assets	(1,321)	(376)
Deferred tax assets	4,707	4,385
Deferred tax liabilities	$ (6,028)	$ (4,761)

Leases - Schedule of Balance Sheet Classification of Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Operating lease liabilities:
Current portion	$ 3,471	$ 2,740
Long-term portion	14,796	15,738
Total operating lease liabilities	18,267	18,478
Finance lease liabilities:
Current portion included in other current liabilities	0	28
Long-term portion included in other long-term liabilities	$ 0	$ 28
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Accounts Payable and Accrued Liabilities	Accounts Payable and Accrued Liabilities
Total finance lease liabilities	$ 0	$ 56
Total lease liabilities	$ 18,267	$ 18,534
Weighted average remaining lease term:
Operating leases	5 years 2 months 12 days	6 years 4 months 24 days
United States of America, Dollars
Weighted average discount rate:
Discount rate	5.90%	5.40%
Canada, Dollars
Weighted average discount rate:
Discount rate	4.80%	4.80%

Cash, Cash Equivalents and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2025

Investments, All Other Investments [Abstract]

Schedule of Marketable Securities

The following table summarizes the Company's marketable securities as of December 31, 2025:


	December 31, 2025
	Amortized Cost		Unrealized Gain (Loss)		Fair Value
Short-term marketable securities:
Contractual maturity of one year or less:
Guaranteed investment certificates (“GICs”) and mutual funds	$	21,920	$	—	$	21,920
U.S. Treasury notes	41,263		36		41,299
Corporate debt securities	124,272		149		124,421
	187,455		185		187,640
Long-term marketable securities:
Contractual maturity of one to three years:
Corporate debt securities	41,388		399		41,787

	41,388		399		41,787

	$	228,843	$	584	$	229,427

The following table summarizes the Company's marketable securities as of December 31, 2024:


	December 31, 2024
	Amortized Cost		Unrealized Gain (Loss)		Fair Value
Short-term marketable securities:
Contractual maturity of one year or less:
GICs	$	37,166	$	—	$	37,166
U.S. Treasury notes	71,500		72		71,572
Corporate debt securities	50,993		(58)		50,935
	159,659		14		159,673
Long-term marketable securities:
Contractual maturity of one to three years:
Corporate debt securities	65,461		(153)		65,308
Contractual maturity of three to four years:
Corporate debt securities	18,295		(156)		18,139
	98,735		(307)		98,428

	$	258,394	$	(293)	$	258,101

Schedule of Assets Measured at Fair Value on a Recurring Basis


	December 31, 2025								December 31, 2024
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash and cash equivalents:
Cash							$	8,968							$	34,620
Cash equivalents:
Money market funds	$	32,189	$	—	$	—	$	32,189	$	16,398	$	—	$	—	$	16,398
GICs	—		—		—		—		15,085		—		—		15,085
	32,189		—		—		41,157		31,483		—		—		66,103

Marketable securities:
GICs and mutual funds	21,920		—		—		21,920		37,166		—		—		37,166
U.S. Treasury notes	41,299		—		—		41,299		86,553		—		—		86,553
Corporate debt securities	—		166,208		—		166,208		—		134,382		—		134,382
	63,219		166,208		—		229,427		123,719		134,382		—		258,101

	$	95,408	$	166,208	$	—	$	270,584	$	155,202	$	134,382	$	—	$	324,204

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2025
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

Leases

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Leases

The lease for the Company’s office and laboratory spaces in Vancouver, British Columbia, which was entered into in January 2019, has an initial term expiring in February 2032, with two five-year extension options. In addition, the Company leases office spaces in Bellevue, Washington and in Redwood City, California with lease terms expiring between August 2027 and July 2029. None of the optional extension periods have been included in the determination of the right-of-use assets or the lease liabilities for operating leases as the Company did not consider it reasonably certain that the Company would exercise any such options.

The Company also leases office equipment under capital lease agreements.

The balance sheet classification of the Company’s lease liabilities was as follows:


	December 31, 2025			December 31, 2024
Operating lease liabilities:
Current portion	$	3,471		$	2,740
Long-term portion	14,796			15,738
Total operating lease liabilities	$	18,267		$	18,478
Finance lease liabilities:
Current portion included in other current liabilities	—			28
Long-term portion included in other long-term liabilities	—			28
Total finance lease liabilities	—			56
Total lease liabilities	$	18,267		$	18,534

Weighted average remaining lease term:
Operating leases	5.2 years			6.4 years
Weighted average discount rate:
Operating leases in U.S. dollars	5.9		%	5.4		%
Operating leases in Canadian dollars	4.8		%	4.8		%

Cash paid for amounts included in the measurement of operating lease liabilities for fixed lease payments for the year ended December 31, 2025 was $4,270 (2024: $4,152) and was included in net cash used in operating activities in the consolidated statement of cash flows. In addition, on April 4, 2024, the Company terminated its long-term facility lease in Seattle, pursuant to which the Company paid $6,075 as a termination fee.

As of December 31, 2025, the maturities of the Company’s operating lease liabilities were as follows:


	Operating leases
Within 1 year	$	4,285
1 to 2 years	4,015
2 to 3 years	3,658
3 to 4 years	5,362
4 to 5 years	2,709
Thereafter	2,935
Total operating lease payments	22,964
Less:
Imputed interest	(4,697)
Operating lease liabilities	$	18,267

The cost components of the operating leases were as follows:


	Year Ended December 31,
	2025		2024		2023
Lease expenses:
Operating lease expense	$	3,355	$	2,447	$	7,292
Variable lease expense	2,257		1,969		1,637
Termination of long-term facility lease in Seattle, net	—		1,033		—
	$	5,612	$	5,449	$	8,929

During the year ended December 31, 2025, the Company recognized $316 of impairment losses on its right-of-use assets (2024: nil and 2023: nil).

Leases

The Company also leases office equipment under capital lease agreements.

The balance sheet classification of the Company’s lease liabilities was as follows:


	December 31, 2025			December 31, 2024
Operating lease liabilities:
Current portion	$	3,471		$	2,740
Long-term portion	14,796			15,738
Total operating lease liabilities	$	18,267		$	18,478
Finance lease liabilities:
Current portion included in other current liabilities	—			28
Long-term portion included in other long-term liabilities	—			28
Total finance lease liabilities	—			56
Total lease liabilities	$	18,267		$	18,534

Weighted average remaining lease term:
Operating leases	5.2 years			6.4 years
Weighted average discount rate:
Operating leases in U.S. dollars	5.9		%	5.4		%
Operating leases in Canadian dollars	4.8		%	4.8		%

As of December 31, 2025, the maturities of the Company’s operating lease liabilities were as follows:


	Operating leases
Within 1 year	$	4,285
1 to 2 years	4,015
2 to 3 years	3,658
3 to 4 years	5,362
4 to 5 years	2,709
Thereafter	2,935
Total operating lease payments	22,964
Less:
Imputed interest	(4,697)
Operating lease liabilities	$	18,267

The cost components of the operating leases were as follows:


	Year Ended December 31,
	2025		2024		2023
Lease expenses:
Operating lease expense	$	3,355	$	2,447	$	7,292
Variable lease expense	2,257		1,969		1,637
Termination of long-term facility lease in Seattle, net	—		1,033		—
	$	5,612	$	5,449	$	8,929

During the year ended December 31, 2025, the Company recognized $316 of impairment losses on its right-of-use assets (2024: nil and 2023: nil).

Income Taxes - Schedule of Income Tax Expense (Recovery) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Current tax provision:
Federal	$ 482
State	(15)
Foreign	(898)
Current income tax expense	(431)	$ (5,393)	$ (189)
Deferred tax provision:
Federal	(845)
State	0
Foreign	(100)
Deferred income tax (expense) recovery	(945)	(691)	757
Income tax (expense) recovery	$ (1,376)	$ (6,084)	$ 568

Commitment and Contingencies - Summary of Changes in Fair Value of the Company's Liability for Contingent Consideration (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Derivative Liability Roll Forward [Roll Forward]
Liability at the beginning of the period	$ 0	$ 1,878
Increase (decrease) in fair value of liability for contingent consideration	0	(1,878)
Amounts paid or transferred to payables	0	0
Liability at end of the period	$ 0	$ 0

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
$
U.S. Federal statutory income tax rate	$ 16,748	$ 24,466	$ 25,041
State & local income tax, net of federal income tax effect	(15)
Tax rate differential		5,360	5,976
Changes in valuation allowance		(28,882)	(78,668)
Other		(108)	(456)
Enactment of new tax laws	0
Foreign Base Company Income	(2,006)
Other	0
Non-taxable or non-deductible items	(122)	(10,508)	(2,696)
Changes in unrecognized tax benefits	(97)
Adjustments to prior year		524	48,724
Change in recognition and measurement of tax positions		(38)	(14)
Changes due to SR&ED and research credits		3,102	2,661
Income tax (expense) recovery	$ (1,376)	$ (6,084)	$ 568
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. Federal statutory income tax rate	21.00%
State & local income tax, net of federal income tax effect	0.00%
Enactment of new tax laws	0.00%
Foreign Base Company Income	(2.50%)
Other	0.00%
Non-taxable or non-deductible items	(0.20%)
Changes in unrecognized tax benefits	(0.10%)
Effective Income Tax Rate	(1.70%)
Canada
$
Tax rate differential	$ (3,980)
Provincial tax rate differential	7,642
Changes in valuation allowance	(15,682)
Effect of cross-border laws	(1,921)
SR&ED Tax Credits	2,971
Stock Based Compensation	(4,065)
Other	$ 91
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Tax rate differential	(5.00%)
Provincial tax rate differential	9.60%
Changes in valuation allowance	(19.70%)
Effect of cross-border laws	(2.40%)
SR&ED Tax Credits	3.70%
Stock Based Compensation	(5.10%)
Other	0.10%
United Kingdom
$
Stock Based Compensation	$ 1,047
Other	$ (16)
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Stock Based Compensation	1.30%
Other	0.00%
All other foreign
$
Tax rate differential	$ (208)
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Tax rate differential	(0.20%)
United States
$
Changes in valuation allowance	$ (3,237)
SR&ED Tax Credits	635
Other	$ 839
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Changes in valuation allowance	(4.10%)
SR&ED Tax Credits	0.80%
Other	1.10%

Business Segments

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Business Segments

The Company operates and manages its business in a single reportable segment, which is the Management of a portfolio of licensed healthcare assets and development of novel multifunctional biotherapeutics (the “biotherapeutics segment”).

The biotherapeutics segment revenue consists of collaboration revenue, including amounts recognized relating to upfront non-refundable payments for licenses or options to obtain future licenses, research and development funding, milestone payments and royalties earned under collaboration and license agreements and is managed on a consolidated basis.

The accounting policies of the biotherapeutics segment are the same as those described in the summary of significant accounting policies.

The Company’s Chief Operating Decision Maker ("CODM”) is the Chair of the Board of Directors and Chief Executive Officer. The CODM assesses performance for the biotherapeutics segment and decides how to allocate resources based on the results of our strategic planning, with segment (loss) income being used to monitor performance against the budgeted costs of that strategy. The measure of segment assets is reported on the balance sheet as total consolidated assets.

Revenue and net income for the Company's biotherapeutics segment are shown below:


	Year Ended December 31,
	2025		2024		2023

Revenue from research and development collaborations	$	105,965	$	76,304	$	76,012

Segment expenses:
Zanidatamab	(1,828)		11,939		44,751
ZW171	9,672		7,151		10,686
ZW191	12,129		8,379		11,714
ZW220	2,922		13,824		1,585
ZW251	11,304		8,103		686
Zanidatamab zovodotin	364		6,595		8,046
Expense for other preclinical and research programs	31,114		17,389		7,819
Salaries and benefits	51,023		50,678		49,931
Other research and development expense	20,581		17,949		19,128
Other general and administrative expense	25,474		29,522		40,823

Total segment expenses	162,755		171,529		195,169

Segment loss	(56,790)		(95,225)		(119,157)

Reconciling items:
Depreciation and amortization	(7,725)		(8,684)		(10,164)
Stock-based compensation expense	(28,034)		(17,792)		(8,102)
Change in contingent consideration	—		1,878		(630)
Impairment	—		(17,287)		—
Interest income	13,354		19,941		19,705
Other income (expense), net	(559)		558		(894)
Income tax (expense) recovery, net	(1,376)		(6,084)		568

Net (loss) income	$	(81,130)	$	(122,695)	$	(118,674)

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Consolidated Statements of Loss and Comprehensive Loss (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Statement [Abstract]
Unrealized loss on available for sale securities, tax	$ 0	$ 0	$ 0

Research, Collaboration and Licensing Agreements - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
License Agreements Research Collaborations And Development Agreements [Abstract]
Contract assets	$ 2,800	$ 100
Contract liabilities	17,000	40,200
Deferred revenue and other consideration (note 11)	$ 2,418	$ 25,588

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 41,157	$ 66,103
Short-term marketable securities (note 5)	187,640	159,673
Accounts receivable	4,638	55,815
Prepaid expenses and other current assets	15,332	18,860
Total current assets	248,767	300,451
Long-term marketable securities (note 5)	41,787	98,428
Long-term prepaids and other assets	6,674	8,919
Deferred tax asset (note 13)	4,707	4,385
Property and equipment, net (note 7)	15,502	17,650
Operating lease right-of-use assets (note 14)	15,724	16,666
Intangible assets, net (note 8)	1,350	4,576
Goodwill (note 6)	12,016	12,016
Total assets	346,527	463,091
Current liabilities:
Accounts payable and accrued liabilities (note 9)	36,346	59,838
Income tax payable (note 13)	83	128
Current portion of operating lease liability (note 14)	3,471	2,740
Deferred revenue and other consideration (note 11)	2,418	25,588
Total current liabilities	42,318	88,294
Long-term portion of operating lease liability (note 14)	14,796	15,738
Deferred revenue (note 11)	14,606	14,607
Other long-term liabilities (note 9)	278	923
Deferred tax liability (note 13)	6,028	4,761
Total liabilities	78,026	124,323
Stockholders’ equity:
Common shares, $0.00001 par value; 900,000,000 authorized shares of common stock at December 31, 2025 and December 31, 2024 (74,638,413 and 68,964,319 shares issued and outstanding at December 31, 2025 and 2024, respectively (note 10b).	1,105,176	1,015,618
Preferred shares, $0.00001 par value; 100,000,000 authorized shares of preferred stock, out of which, one share of preferred stock is a share of Special Voting Preferred Stock and outstanding as of December 31, 2025 and December 31, 2024 (note 10b).	0	0
Exchangeable shares, no par value, 553,184 issued and outstanding shares at December 31, 2025 (December 31, 2024: 570,637) (note 10b).	7,938	8,188
Additional paid-in capital	114,626	152,249
Accumulated other comprehensive loss	(6,079)	(6,952)
Accumulated deficit	(953,160)	(830,335)
Total stockholders’ equity	268,501	338,768
Total liabilities and stockholders’ equity	346,527	463,091
Commitments and contingencies (note 15)

Research, Collaboration and Licensing Agreements

12 Months Ended

Dec. 31, 2025

License Agreements Research Collaborations And Development Agreements [Abstract]

Research, Collaboration and Licensing Agreements

Revenue recognized from the Company’s strategic partnerships is summarized as follows:


	Year ended December 31,
	2025		2024		2023
Jazz:
Milestone revenue	$	—	$	25,000	$	—
Development support payments	5,616		2,835		52,619
Drug supply for ongoing studies	6,548		19,228		25,662
Credit note for amendment of program	—		—		(20,100)
Other drug supply	2,103		15,464		13,350
Royalties	2,481		100		—

BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”):
Milestone revenue	20,000		8,000		—
Recognition of deferred revenue	18,334		—		—
Drug supply	762		3,009		1,080
Development support payments	—		—		537
Royalties	271		—		—

Johnson & Johnson Innovative Medicine (previously known as Janssen Biotech, Inc.) (“J&J”):
Milestone revenue	25,000		—		—

GlaxoSmithKline Intellectual Property Development Ltd. (“GSK”):
Milestone revenue	14,000		2,500		—

Bristol-Myers Squibb (“BMS”):
Option exercise fee	7,500		—		—

Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”):
Milestone revenue	3,100		—		—

Merck Sharp & Dohme LLC (“Merck”)
Research period extension fee	250		—		—

Research and development support and other payments	—		168		2,864
	$	105,965	$	76,304	$	76,012

Contract Assets and Liabilities

As at December 31, 2025, contract assets from research, collaboration and licensing agreements were $2.8 million, which is presented within accounts receivable (December 31, 2024: $0.1 million which is presented within accounts receivable) and contract liabilities were $17.0 million (December 31, 2024: $40.2 million). As at December 31, 2025 and 2024, $2.4 million and $25.6 million respectively, of the contract liabilities is classified as short term. Contract liabilities relate to deferred revenue from the BeOne and Jazz agreements described below.

Jazz Collaboration Agreement

Original Jazz Collaboration Agreement:

On October 18, 2022, the Zymeworks BC entered into a License and Collaboration Agreement (the "Jazz Collaboration Agreement") with Jazz Pharmaceuticals Ireland Limited ("Jazz"), under which Jazz will have development and commercialization rights of zanidatamab throughout the world, but excluding the People’s Republic of China, Australia, New Zealand, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, Hong Kong, Taiwan, Macau, Mongolia, South Korea, Brunei Darussalam, Cambodia, Indonesia, Papua New Guinea, Lao People’s Democratic Republic, Malaysia, Myanmar, Philippines, Singapore, Thailand, Timor-Leste, and Vietnam.

Under the Jazz Collaboration Agreement, the Company received a $50.0 million upfront payment upon delivery of licenses and technology transfer to Jazz as well as the receipt of United States Hart-Scott Rodino Antitrust Improvements Act of 1976 (“HSR”) Clearance (“Initial Technology Transfer”). A further payment of $325.0 million was received following Jazz's decision to continue the collaboration after readout of the top-line clinical data from HERIZON-BTC-01 (“BTC Data Transfer”). The Company considered the fair value of performance obligations based on the Company’s best estimate of their relative stand-alone selling prices, and allocated $375.0 million of the transaction price to the Company’s performance obligations in relation to the delivery of licenses, the Initial Technology Transfer and BTC Data Transfer under the Jazz Collaboration Agreement.

Development and commercial licenses, the Initial Technology and BTC Data Transfers were considered to be a single performance obligation. The consideration of $50.0 million allocated to this performance obligation was recognized as revenue in November 2022, upon delivery of these performance obligations and receipt of the HSR Clearance. Remaining consideration of $325.0 million was recognized as revenue upon completion of BTC Data Transfer to Jazz and Jazz’s decision to continue the Jazz Collaboration agreement, in December 2022.

Deliverables of development work performed by the Company, continuing technology transfer, participation in the Joint Steering Committee (“JSC”), and transfer of first BLA together were considered to be a single performance obligation and the consideration allocated to this performance obligation will be recognized as revenue over time as these activities are completed.

Remaining deliverables of Manufacturing Technology Transfer, Development Drug Supply, Commercial Drug Supply were considered individually distinct and the revenue related to these deliveries are to be recognized upon completion of future deliveries to Jazz.

Amendment of Jazz Collaboration Agreement:

On April 25, 2023, Zymeworks BC, a subsidiary of the Company, Zymeworks Biopharmaceuticals Inc. (“ZBI”), a subsidiary of Zymeworks BC, Zymeworks Zanidatamab Inc. (“ZZI”), a subsidiary of ZBI formed in December 2022 focused on the Company’s development program for zanidatamab, and Jazz Pharmaceuticals, Inc. (“Jazz Inc.”), entered into a Stock and Asset Purchase Agreement (the “Transfer Agreement”). Under the Transfer Agreement, (i) Jazz Inc. acquired from ZBI 100% of the issued and outstanding capital stock of ZZI, (ii) Jazz Inc. engaged certain Zymeworks BC and ZZI employees associated with the development of zanidatamab, and (iii) Zymeworks BC and ZBI transferred to Jazz Inc. or one of its affiliates contracts with respect to the engagement of certain independent contractors of Zymeworks BC and ZBI that work on the Program (as defined below). In addition, Jazz Inc. acquired from Zymeworks BC and ZBI certain contracts related to the Program, organizational documents and other records of ZZI, certain regulatory filings related to the Program, certain other books, records and other files, documents and information related to the Program, and certain employment records of service providers to be employed by Jazz Inc. and its affiliates following the Closing (as defined below). Subject to the terms and conditions of the Transfer Agreement, Jazz Inc. assumed certain liabilities that arise following the Closing related to the acquired assets and the Program, including with respect to transferred service providers.

Zymeworks BC and Jazz Pharmaceuticals Ireland Limited (an affiliate of Jazz Inc.) (a subsidiary of Jazz Pharmaceuticals plc, collectively referred to as “Jazz”) amended and restated the license and collaboration agreement dated October 18, 2022 by and between Zymeworks BC and Jazz (the “Original Jazz Collaboration Agreement”) (as amended the “Amended Jazz Collaboration Agreement”) to reflect the transfer of responsibility for the Program. Under the Amended Jazz Collaboration Agreement, the financial terms of the Original Jazz Collaboration Agreement, as previously disclosed, was unchanged, except that the costs of the Program (including ongoing costs related to the transferred service providers) incurred following the Closing was directly borne by Jazz instead of being incurred by Zymeworks BC and charged back to Jazz for reimbursement, though Zymeworks BC will remain eligible for reimbursement of certain costs for activities where Zymeworks BC maintains responsibility under the Amended Jazz Collaboration Agreement. As part of the amendments to the Amended Collaboration Agreement, the Company agreed to provide a credit note to Jazz of $20.1 million, which has been recognized as a reduction to

revenue for the year ended December 31, 2023. “Program” refers to (i) ongoing clinical trials in certain sites in South Korea that are the responsibility of Zymeworks BC under the Original Jazz Collaboration Agreement and (ii) clinical trials for zanidatamab, other than the studies referenced in (i), initiated by Zymeworks BC in the Territory (as defined in the Original Jazz Collaboration Agreement) prior to the execution of the Original Jazz Collaboration Agreement.

The consummation of the transactions contemplated by the Transfer Agreement, including the execution of the Amended Jazz Collaboration Agreement, occurred in May 2023 (the “Closing”). In connection with the Closing, the parties entered into a transition services agreement pursuant to which Zymeworks BC and ZBI provide to Jazz Inc. and Jazz Inc. provides to Zymeworks BC and ZBI certain services to support the transfer of the acquired assets and the Program on a transitional basis.

In November 2024, the Company recognized milestone revenue of $25.0 million from Jazz in relation to the FDA approval of Ziihera (zanidatamab-hrii) for the treatment of HER2+ BTC. As at December 31, 2025, the Company is eligible to receive up to $500.0 million in certain regulatory milestone payments and up to $862.5 million in potential commercial milestone payments. The Company is eligible to receive tiered royalties between 10% and 20% on Jazz’s annual net sales, with customary reductions in specified circumstances. No commercial milestone payments have been recognized to date.

As at December 31, 2025, contract liabilities under the Amended Jazz Collaboration Agreement include $2.4 million received in relation to drug supply provided to Jazz.

Collaboration and License Agreements with BeOne, Ltd. (“BeOne”)

On November 26, 2018, the Company entered into three concurrent agreements with BeOne whereby the Company granted BeOne royalty-bearing exclusive licenses for the research, development and commercialization of its bispecific therapeutic candidates, zanidatamab (formerly known as “ZW25”) (as amended on March 29, 2021 and August 10, 2021 and as otherwise modified, collectively “Zanidatamab Agreement”) and zanidatamab zovodotin (formerly known as “ZW49”) (as amended on May 25, 2020 and June 2, 2021, collectively “Zanidatamab Zovodotin Agreement”) in Asia (excluding Japan but including the People’s Republic of China, South Korea and other countries), Australia and New Zealand. In addition, the Company also granted BeOne a worldwide, royalty-bearing, antibody sequence pair-specific license to research, develop and commercialize globally three bispecific antibodies generated through the use of the Company’s Azymetric and EFECT platforms, which agreement expired in November 2023.

Pursuant to these agreements, the Company received an upfront payment of $60.0 million for the totality of the rights described. The Company considered the fair value of performance obligations based on the Company’s best estimate of their relative stand-alone selling prices, and allocated $40.0 million of the transaction price to the license and collaboration agreements for zanidatamab and zanidatamab zovodotin and $20.0 million to the Company’s performance obligations under the research and licensing agreement for Azymetric and EFECT platforms.

Original License and Collaboration Agreements for Zanidatamab and Zanidatamab Zovodotin

In relation to the Zanidatamab Agreement, the Company identified the following promised goods and services at the inception of the BeOne agreement that are material: development and commercial licenses, initial transfer of the Company’s technologies and relevant know-how, continuing technology transfer, participation in the Joint Steering Committee (“JSC”) and other sub-committees, manufacturing technology transfer, provision of development supply, provision of commercial supply, and transfer of future rights related to the development and commercial license. The Company concluded that the licenses and initial technology transfer are distinct together and the continuing technology transfer and the Company’s participation to the JSC and other sub-committees’ activities are also distinct together. Remaining deliverables were individually determined to be distinct.

Development and commercial licenses as well as initial transfer of technologies and relevant know-how were considered to be a single performance obligation. The consideration of $7.1 million allocated to this performance obligation was recognized as revenue over a two-month period during which the delivery of the license and transfer of the relevant technology occurred. Deliverables of continuing technology transfer and participation in the JSC and other sub-committees together were considered to be a single performance obligation and the consideration allocated to this performance obligation will be recognized as revenue over time as these activities are completed. Remaining deliverables are considered individually distinct and the revenue will be recognized as delivery or transfer of future rights to BeOne occurs.

In March 2020, BeOne dosed the first patient in a two-arm Phase 1b/2 trial evaluating zanidatamab in combination with chemotherapy as a first-line treatment for patients with metastatic HER2+ breast cancer and in combination with chemotherapy and BeOne’s PD-1-targeted antibody tislelizumab as a first-line treatment for patients with metastatic HER2+ GEA. The Company recognized revenue of $5.0 million in relation to this milestone. In November 2020, BeOne dosed the first patient in

South Korea in the pivotal HERIZON-BTC-01 study. The Company recognized revenue of $10.0 million in relation to this milestone. In December 2021, BeOne dosed the first patient in South Korea in the pivotal HERIZON-GEA-01 study and the Company recognized revenue of $8.0 million in relation to this milestone.

In relation to the Zanidatamab Zovodotin Agreement, the Company identified the following promised goods and services at the inception of the BeOne agreement that are material: development and commercial licenses, initial transfer of the Company’s technologies and relevant know-how, continuing technology transfer, participation in the JSC and other sub-committees, manufacturing technology transfer, provision of development supply, provision of commercial supply, and transfer of future rights related to the development and commercial license. The Company concluded that the licenses and initial technology transfer together were distinct together and the continuing technology transfer and the Company’s participation to the JSC and other sub-committees’ activities were also distinct together. Manufacturing technology transfer, provision of development supply and provision of commercial supply were individually determined to be distinct.

Development and commercial licenses as well as initial transfer of technologies and relevant know-how were considered to be a single performance obligation while continuing technology transfer and participation in the JSC and other sub-committees together were considered as a single performance obligation. Remaining deliverables were considered individually distinct.

Termination of BeOne License and Collaboration Agreement Regarding Zanidatamab Zovodotin and Amendment of BeOne License and Collaboration Agreement Regarding Zanidatamab:

On September 18, 2023, Zymeworks BC and BeOne entered into a Termination Agreement (the “Termination Agreement”) relating to the Zanidatamab Zovodotin Agreement. The Termination Agreement does not terminate the Zanidatamab Agreement (as defined below).

Pursuant to the Termination Agreement, the Zanidatamab Zovodotin Agreement is terminated, effective as of September 18, 2023, and is no longer in effect, except that the termination does not relieve the parties from obligations under the Zanidatamab Zovodotin Agreement that accrued prior to the termination and certain other provisions expressly indicated to survive the termination, including certain licenses to BeOne intellectual property with respect to zanidatamab zovodotin.

Under the Zanidatamab Zovodotin Agreement, no performance obligations were completed by the Company as the initial transfer of technologies and relevant know-how was not going to start until the earlier of completion of the Company’s Phase-1 clinical studies for zanidatamab zovodotin or completion of dose escalation studies. Accordingly, no revenue was recognized from the Zanidatamab Zovodotin Agreement to date.

In connection with the entry into the Termination Agreement, on September 18, 2023, Zymeworks BC and BeOne also entered into the Third Amendment to License and Collaboration Agreement (the “Amendment”) relating to the Zanidatamab Agreement. Pursuant to the Amendment, Zymeworks BC is eligible to receive development and commercial milestone payments of up to $144.0 million, together with tiered royalties up to 19.5% of annual net sales in BeOne territories increasing up to 20% when cumulative amounts forgone as a result of a royalty reduction of 0.5% reaches a cap in the low double-digit millions of dollars. Pursuant to the Amendment, the remaining provisions of the Zanidatamab Agreement remain unchanged.

The Termination Agreement and the Amendment did not have any financial impact on the Company's financial statements, other than allocation of consideration and performance obligations under the Zanidatamab Zovodotin Agreement to Zanidatamab Agreement. As of December 31, 2025, $14.6 million of the upfront fees is recorded as long-term deferred revenue on the Company’s consolidated balance sheet (December 31, 2024: $18.3 million as deferred revenue in current liabilities and $14.6 million as deferred revenue in long-term deferred revenue). Amounts not expected to be recognized as revenue within the next twelve months of the consolidated balance sheet date are classified as long-term deferred revenue.

In June 2024, the Company recognized $8.0 million of milestone revenue from BeOne in relation to the acceptance by the CDE of the NMPA in China of the BLA for zanidatamab for second-line treatment of HER2+ BTC. In May 2025, the Company recognized $20.0 million in non-refundable milestone revenue from BeOne upon approval of the BLA for zanidatamab for second-line treatment of HER2+ BTC by the NMPA in China. The Company also recognized $18.3 million of deferred revenue in relation to achievement of this milestone.

2020 Research and License Agreement with Merck

In July 2020, the Company entered into a new licensing agreement with Merck granting Merck a worldwide, royalty-bearing license to research, develop and commercialize up to three new multispecific antibodies toward Merck’s therapeutic targets in the human health field and up to three new multispecific antibodies toward Merck’s therapeutic targets in the animal health field using the Company’s Azymetric and EFECT platforms. The Company is eligible to receive up to $419.3 million in option exercise fees and clinical development and regulatory approval milestone payments and up to $502.5 million in commercial milestone payments, as well as tiered royalties on worldwide sales.

Licensing and Collaboration Agreement with Celgene Corporation & Celgene Alpine Investment Co. LLC (formerly “Celgene” and now a Bristol- Myers Squibb company, “BMS”)

On December 23, 2014, the Company entered into an agreement with Celgene (now “BMS”) to research, develop and commercialize bispecific antibodies generated through the use of the Company’s Azymetric platform. The Company will apply its Azymetric platform in combination with BMS’s proprietary targets to create novel bispecific antibodies for which BMS has an option to develop and commercialize a certain number of products (“Commercial License Option”).

Upon the execution of the Agreement, the Company received an upfront payment of $8.0 million. This agreement was expanded in 2018 to increase the number of programs from eight to ten and to extend BMS’s research period and the Company received an expansion fee of $4.0 million. In June 2020, the Company’s existing collaboration agreement with BMS was amended to expand the license grant to include the use of the Company’s EFECT platform for the development of therapeutic candidates and to extend the research term. The amendment included an upfront expansion fee of $12.0 million paid to the Company and all other financial terms were unchanged. The Company’s performance obligations in relation to the upfront fee were met on the date of amendment. Accordingly, the upfront payment was recognized as revenue during the year ended December 31, 2020. As of December 31, 2025, BMS had exercised two commercial license options and the Company received $15.0 million of option payments in total, but in 2023 BMS stopped development of one of these programs. BMS’s right to exercise options on eight programs expired in 2024 after the conclusion of BMS’s research period. As at December 31, 2025, the Company remains eligible to receive up to $313.0 million for the two remaining programs (or $156.5 million not including the one program for which BMS stopped development in 2023), comprised of development milestone payments of up to $101.5 million per program, and commercial milestone payments of up to $55.0 million per program. In addition, the Company is eligible to receive tiered royalties calculated upon the global net sales of the resulting products. BMS will have exclusive worldwide commercialization rights to products derived from the agreement for those product candidates that BMS elected to exercise its commercial license option. As BMS’s research period has concluded, BMS is solely responsible for the research, development, manufacturing and commercialization of the products.

2015 Collaboration and License Agreement with GlaxoSmithKline Intellectual Property Development Ltd. (“GSK”)

On December 1, 2015, the Company entered into a collaboration and license agreement with GSK for the research, development, and commercialization of up to ten Fc-engineered monoclonal and bispecific antibodies generated through the use of the Company’s EFECT and Azymetric platforms. The Company and GSK will collaborate to further develop the Company’s EFECT platform through the design, engineering, and testing of novel engineered Fc domains tailored to induce specific antibody-mediated immune responses.

At the conclusion of the research collaboration, both GSK and the Company will have the right to develop and commercialize monoclonal and bispecific antibody candidates that incorporate the Company’s optimized immune-modulating Fc domains.

Under the terms of the agreement, GSK will have the right to develop a minimum of four products across multiple disease areas, and the Company will be eligible to receive up to $1.1 billion, including research, development, and commercial milestones of up to $110.0 million for each product. In addition, the Company is eligible to receive tiered sales royalties in the low single digits on net sales of products. Under this agreement, the Company is sharing certain research and development responsibilities with GSK to generate new Fc-engineered antibodies. Each party will bear its own costs for the responsibilities assigned to it during the research period. Furthermore, the Company will have the right to develop up to four products, free of royalties, using the new intellectual property arising from the collaboration and after a period of time, to grant licenses to such

intellectual property for development of additional products by third parties without any royalty or milestone payment to GSK. The Company determined that, the events and conditions resulting in payments for research, development and commercial milestones solely depend on GSK’s performance.

No development or commercial milestone payments or royalties have been received to date.

2016 Platform Technology Transfer and License Agreement with GSK

On April 21, 2016, the Company entered into a platform technology transfer and license agreement with GSK for the research, development, and commercialization of up to six bispecific antibodies enabled using the Company’s Azymetric platform. Each of the two agreements with GSK were negotiated independently and the deliverables covered by the respective contracts utilize different therapeutic platforms and are unrelated to one another. Accordingly, the Platform Technology and License Agreement with GSK has been accounted for as a new arrangement. In May 2019, this agreement was expanded to provide GSK access to the Company’s unique heavy-light chain pairing technology under the Azymetric platform. This may include bispecific antibodies incorporating new engineered Fc regions generated under the 2015 GSK agreement.

The Company is eligible to receive up to $1.1 billion in milestone and other payments. From contract inception to December 31, 2025, the Company has received an upfront technology access fee payment of $6.0 million. In July 2024, the Company recognized $2.5 million of milestone revenue from GSK in relation to the sequence pair nomination by GSK under the 2016 agreement between the Company and GSK. Furthermore, in January 2025, the Company recognized $14.0 million of milestone revenue associated with a clinical milestone. As of December 31, 2025, the Company is also eligible to receive research milestone payments of up to $35.0 million, development milestone payments of up to $168.5 million and commercial milestone payments of up to $867.0 million. In addition, the Company is entitled to receive tiered royalties in the low to mid-single digits on product sales. The Company determined that, the events and conditions resulting in payments for research, development and commercial milestones solely depend on GSK’s performance.

No commercial milestone payments or royalties have been received to date.

2016 Collaboration Agreement with Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”)

On September 26, 2016, the Company and Daiichi Sankyo entered into a collaboration and cross license agreement which was amended on September 25, 2018, July 2, 2021, and June 6, 2022 (collectively, the “2016 Daiichi Collaboration Agreement”) for the research, development, and commercialization of one bispecific antibody enabled using the Company’s Azymetric and EFECT platforms. Additionally, the Company was able to license immuno-oncology antibodies from Daiichi Sankyo, with the right to research, develop and commercialize multiple products globally in exchange for royalties on product sales. Under the agreement, Daiichi Sankyo had the option to develop and commercialize a single bispecific immuno-oncology therapeutic.

From contract inception to the termination of 2016 Daiichi Collaboration agreement as defined below, the Company has received an upfront technology access fee payment of $2.0 million and research and commercial option related payments totaling $4.5 million.

Termination of the 2016 Daiichi Sankyo Collaboration Agreement

In March 2023, Zymeworks BC and Daiichi Sankyo terminated the 2016 Daiichi Collaboration Agreement and is no longer in effect, except that the termination does not relieve the parties from obligations under the 2016 Daiichi Collaboration Agreement that have accrued prior to the termination or provisions of the 2016 Daiichi Collaboration Agreement expressly indicated in the 2016 Daiichi Collaboration Agreement or the Termination and License Agreement to survive the termination. The termination of the 2016 Daiichi Collaboration Agreement did not have any financial impact during the year ended December 31, 2023.

2018 Licensing Agreement with Daiichi Sankyo

In May 2018, the Company entered into a second license agreement with Daiichi Sankyo to research, develop and commercialize two bispecific antibodies generated through the use of the Company’s Azymetric and EFECT platforms. Under the terms of the agreement, the Company granted Daiichi Sankyo a worldwide, royalty-bearing, antibody sequence pair-specific, exclusive license to research, develop and commercialize certain products. Under the agreement, Daiichi Sankyo will be solely responsible for the research, development, manufacturing and commercialization of the products.

Under the terms of the agreement, the Company was eligible to receive up to $484.7 million in various milestone and other payments. At inception, the Company received an upfront technology access fee payment of $18.0 million. In March 2025, the Company recognized $3.1 million of milestone revenue from Daiichi Sankyo following the first patient dosed in a clinical trial related to the 2018 license agreement between the Company and Daiichi Sankyo. As of December 31, 2025, the Company remains eligible to receive development milestone payments totaling up to $60.3 million and commercial milestone payments of up to $170.0 million. In addition, the Company is eligible to receive tiered royalties ranging from the low single digits up to 10% on product sales, with the royalty term being, on a product-by-product and country-by-country basis, either (i) for as long as there is Zymeworks platform patent coverage on products, or (ii) for 10 years beginning from the first commercial sale, whichever period is longer. If there is no Zymeworks patent coverage on products, royalty rates may be reduced.

No development or commercial milestone payments or royalties have been received to date.

Collaboration and License Agreement with Janssen Biotech, Inc. (“Janssen”)

On November 13, 2017, the Company entered into a collaboration and license agreement with Janssen to research, develop and commercialize up to six bispecific antibodies generated through the use of the Company’s Azymetric and EFECT platforms. Under the terms of the agreement, the Company granted Janssen a worldwide, royalty-bearing, antibody group-specific

exclusive license to research, develop and commercialize certain products. Janssen also has the option to develop two additional bispecific antibodies under this agreement subject to a future option payment. Under the agreement, Janssen will be solely responsible for the research, development, manufacturing and commercialization of the products.

The Company was originally eligible to receive up to $1.45 billion in various license and milestone payments. From contract inception to December 31, 2025, the Company has received an upfront payment of $50.0 million and development milestones totaling $33.0 million which included $8.0 million in connection with the initiation of clinical trials of two bispecific antibodies and $25.0 million related to clinical progress of pasritamig entering into a Phase 3 trial in metastatic castration-resistant prostate cancer. Pasritamig is a first-in-class, bispecific T-cell engager targeting human kallikrein 2 (KLK2), engineered using Zymeworks’ Azymetric platform. Janssen has deprioritized the development of one of those two bispecific antibodies, and in 2023 the research program term under the agreement ended with respect to the remaining four bispecific antibodies. As a result, the Company remains eligible to receive development milestone payments of up to $61.0 million and commercial milestone payments of up to $373.0 million ($18.0 million and $186.5 million, respectively, not including the bispecific antibody that Janssen has deprioritized). In addition, the Company is eligible to receive tiered royalties in the mid-single digits on product sales, with the royalty term being, on a product-by-product and country-by-country basis, either (i) for as long as there is Zymeworks platform patent coverage on products, or (ii) for 10 years, beginning from the first commercial sale, whichever period is longer. If there is no Zymeworks patent coverage on products, royalty rates may be potentially reduced. Janssen has the right, prior to the first dosing of a patient in a Phase 3 clinical trial for a product, to buy down the royalty relating to such product by one percentage point with a payment of $10.0 million. The Company determined that, the events and conditions resulting in payments for research, development and commercial milestones solely depend on Janssen’s performance.

No commercial milestone payments or royalties have been received to date.

Research and License Agreement with LEO Pharma A/S (“LEO”)

On October 23, 2018, the Company entered into a research and license agreement with LEO. The Company granted LEO a worldwide, royalty-bearing, antibody sequence pair-specific exclusive license to research, develop and commercialize two bispecific antibodies, generated through the use of the Company’s Azymetric and EFECT platforms, for dermatologic indications. The Company will retain rights to develop antibodies resulting from this collaboration in all other therapeutic areas. The Company and LEO are jointly responsible for certain research activities, with the Company’s cost to be fully reimbursed by LEO. Each party is solely responsible for the development, manufacturing, and commercialization of their own products.

Pursuant to this agreement, the Company received an upfront payment of $5.0 million. No development or commercial milestone payments or royalties have been received to date.

Termination of LEO Research and License Agreement

On October 27, 2023, Zymeworks BC received written notice from LEO Pharma A/S (“LEO”), stating that LEO elected to terminate, in its entirety, the Research and License Agreement. In accordance with the terms of the Research and License Agreement, the termination of such agreement was effective on January 25, 2024. The termination of the LEO Research and License Agreement did not have any financial impact during the year ended December 31, 2023.

Leases - Schedule of Cost Components of Operating Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Operating lease expense	$ 3,355	$ 2,447	$ 7,292
Variable lease expense	2,257	1,969	1,637
Termination of long-term facility lease in Seattle, net	0	1,033	0
Operating lease expense	$ 5,612	$ 5,449	$ 8,929

Property and Equipment

12 Months Ended

Dec. 31, 2025

Property, Plant and Equipment [Abstract]

Property and Equipment

Property and equipment consist of the following:


	December 31,
	2025		2024
Computer hardware	$	3,233	$	2,815
Furniture and fixtures	1,850		2,408
Office equipment	1,674		1,736
Laboratory equipment	13,838		13,331
Leasehold improvements	15,243		15,190
Construction in progress	540		—
Property and equipment	$	36,378	$	35,480
Less accumulated depreciation	(20,876)		(17,830)
Property and equipment, net	$	15,502	$	17,650

Depreciation expense on property and equipment for the years ended December 31, 2025, 2024 and 2023 was $3,669, $4,188 and $7,462, respectively.

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2025
Audit Information [Abstract]
Auditor Firm ID	85
Auditor Name	KPMG LLP
Auditor Location	Vancouver, Canada

Research, Collaboration and Licensing Agreements - Collaboration and License Agreements with BeiGene, Ltd. (Details) $ in Thousands			1 Months Ended				12 Months Ended
	Sep. 18, 2023 USD ($)	Nov. 26, 2018 USD ($) Agreement antibody	May 31, 2025 USD ($)	Dec. 31, 2021 USD ($)	Nov. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)							$ 105,965	$ 76,304	$ 76,012
Contract liabilities							17,000	40,200
Deferred revenue and other consideration (note 11)							2,418	25,588
Deferred revenue (note 11)							14,606	14,607
Collaborative Arrangement \| BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| License and Collaboration
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 144,000
Royalty payments on future global net sales (up to)	19.50%
Royalty percentage earned from sales of product (up to)	20.00%
Percentage of royalty reduction	0.50%
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”):
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract liabilities							14,600
Deferred revenue and other consideration (note 11)								18,300
Deferred revenue (note 11)								14,600
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				$ 8,000	$ 10,000	$ 5,000
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)			$ 20,000				$ 20,000	$ 8,000	$ 0
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Deferred Revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)			$ 18,300
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of agreements \| Agreement		3
Number of antibodies \| antibody		3
Proceeds from collaboration agreement										$ 60,000
Fair value of consideration allocated to a group of contracts that were considered as a single contract										40,000
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| License Agreement \| Collaborative Arrangement \| ZW25 Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Fair value of consideration allocated to a group of contracts that were considered as a single contract		$ 7,100
BeOne Medicines Ltd. (previously known as BeiGene, Ltd.) (“BeOne”): \| Research and License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Fair value of consideration allocated to a group of contracts that were considered as a single contract										$ 20,000

Cash, Cash Equivalents and Marketable Securities - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Contractual maturity of one year or less:
Debt securities, amortized cost	$ 187,455	$ 159,659
Debt securities, unrealized gain (loss)	185	14
Debt securities, fair value	187,640	159,673
Contractual maturity of three to four years:
Investments, cost	41,388	98,735
Unrealized Gain (Loss)	399	(307)
Investments, fair value	41,787	98,428
Debt securities, available-for-sale, amortized cost, excluding accrued interest, before allowance for credit loss	228,843	258,394
Debt securities, unrealized gain (loss)	584	(293)
Debt securities, available-for-sale, excluding accrued interest	229,427	258,101
Guaranteed investment certificates (“GICs”) and mutual funds
Contractual maturity of one year or less:
Debt securities, amortized cost	21,920	37,166
Debt securities, unrealized gain (loss)	0	0
Debt securities, fair value	21,920	37,166
Contractual maturity of three to four years:
Debt securities, available-for-sale, excluding accrued interest	21,920	37,166
U.S. Treasury notes
Contractual maturity of one year or less:
Debt securities, amortized cost	41,263	71,500
Debt securities, unrealized gain (loss)	36	72
Debt securities, fair value	41,299	71,572
Contractual maturity of three to four years:
Debt securities, available-for-sale, excluding accrued interest	41,299	86,553
Corporate debt securities
Contractual maturity of one year or less:
Debt securities, amortized cost	124,272	50,993
Debt securities, unrealized gain (loss)	149	(58)
Debt securities, fair value	124,421	50,935
Contractual maturity of one to three years:
Debt securities, amortized cost	41,388	65,461
Debt securities, unrealized gain (loss)	399	(153)
Debt securities, fair value	41,787	65,308
Contractual maturity of three to four years:
Debt securities, amortized cost		18,295
Debt securities, unrealized gain (loss)		(156)
Debt securities, fair value		18,139
Debt securities, available-for-sale, excluding accrued interest	$ 166,208	$ 134,382

Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 26,437	$ 25,606
Less accumulated amortization	(25,087)	(21,030)
Intangible assets, net	1,350	4,576
Research licenses
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	14,936	14,936
Computer software
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 11,501	$ 10,670

- 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

Research, Collaboration and Licensing Agreements - 2018 Licensing Agreement with Daiichi Sankyo (Details)		12 Months Ended			91 Months Ended
	May 30, 2018 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2025 USD ($)	May 31, 2018 antibody
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 105,965,000	$ 76,304,000	$ 76,012,000
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Upfront Fee
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)					$ 18,000,000.0
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Commercial and Development Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)					$ 0
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| License Agreement \| Arrangement Other than Collaborative
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody						2
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Eligible to Receive \| License Agreement \| Arrangement Other than Collaborative \| Royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty agreement term		10 years
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Maximum \| Eligible to Receive \| License Agreement \| Arrangement Other than Collaborative
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 484,700,000
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Maximum \| Eligible to Receive \| License Agreement \| Arrangement Other than Collaborative \| Development Milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 60,300,000
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Maximum \| Eligible to Receive \| License Agreement \| Arrangement Other than Collaborative \| Commercial Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 170,000,000.0
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Maximum \| Eligible to Receive \| License Agreement \| Arrangement Other than Collaborative \| Royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty percentage earned from sales of product		10.00%

Summary of Significant Accounting Policies - Concentration of Credit Risk (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2025 CAD ($)	Dec. 31, 2024 CAD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum exposure to credit risk for accounts receivable	$ 4,638	$ 55,815
Net monetary assets denominated in foreign currency	$ 4,337		$ 5,946
Net monetary liabilities denominated in foreign currency		$ 3,464		$ 4,982
Jazz: \| Accounts Receivable \| Credit Concentration Risk
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Concentration risk, percentage	37.00%	95.00%

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References + Details

Net Loss per Share

12 Months Ended

Dec. 31, 2025

Earnings Per Share [Abstract]

Net Loss per Share

Net loss per share for the years ended December 31, 2025, 2024 and 2023 was as follows:


	Year Ended December 31,
	2025		2024		2023
Numerator:
Net loss attributable to common stockholders:
Basic	$	(81,130)	$	(122,695)	$	(118,674)
Adjustment for change in fair value of liability classified stock options	(196)		140		—
Diluted	$	(81,326)	$	(122,555)	$	(118,674)

Denominator:
Weighted-average common stock outstanding:
Basic	75,404,897		75,846,681		68,863,010
Adjustment for dilutive effect of liability classified stock options	8,499		32,057		—
Diluted	75,413,396		75,878,738		68,863,010

Net loss per common share – basic	$	(1.08)	$	(1.62)	$	(1.72)
Net loss per common share – diluted	$	(1.08)	$	(1.62)	$	(1.72)

Weighted average number of shares of common stock used in the basic and diluted earnings per share calculations include Exchangeable Shares and the pre-funded warrants issued in connection with the Company’s offerings and private placements as the warrants were exercisable at any time for nominal cash consideration. The Company’s potentially dilutive securities, which include stock options and RSUs, have been excluded from the computation of diluted net loss per share for the years ended December 31, 2025, 2024 and 2023 as the effect would be antidilutive.

Nature of Operations	12 Months Ended
Nature of Operations	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations Zymeworks Inc. together with its subsidiaries (collectively the “Company” or “Zymeworks”) is a global biotechnology company managing a portfolio of licensed healthcare assets and developing a diverse pipeline of novel, multifunctional biotherapeutics to improve the standard of care for difficult-to-treat diseases, including cancer, inflammation, and autoimmune disease. Zymeworks BC Inc. (“Zymeworks BC”), (previously known as “Zymeworks Inc.”) was incorporated on September 8, 2003 under the laws of the Canada Business Corporations Act. On October 22, 2003, the Company was registered as an extra-provincial company under the Company Act (British Columbia). On May 2, 2017, the Company continued under the Business Corporations Act (British Columbia). Since its inception, the Company has devoted substantially all of its resources to research and development activities, including developing its therapeutic platforms and identifying and developing potential product candidates by undertaking preclinical studies and clinical trials. The Company supports these activities through general and administrative support, as well as by raising capital, conducting business planning and protecting its intellectual property. On October 13, 2022, the Company completed an internal reorganization transaction resulting in a Delaware incorporated entity becoming the listed company (the “Redomicile Transactions”). Prior to the Redomicile Transactions, the shares of Zymeworks BC Inc. (formerly known as Zymeworks Inc.) were publicly listed. To effect the Redomicile Transactions, the Company conducted a share exchange, pursuant to which holders of the Company’s common shares exchanged their common shares in the Company for shares of common stock of Zymeworks Inc. (formerly known as Zymeworks Delaware Inc.) or, at their election with respect to all or a portion of their common shares in the Company and subject to applicable eligibility criteria and an overall cap, exchangeable shares (the “Exchangeable Shares”) in the capital of a newly formed indirect subsidiary of Zymeworks Inc. A special meeting of Company security holders was held on October 7, 2022 to approve the Redomicile Transactions. The Redomicile Transactions were governed by a transaction agreement dated July 14, 2022, as restated and amended on August 18, 2022 (the “Restated and Amended Transaction Agreement”), by and among the Company and its direct or indirect subsidiaries Zymeworks Inc., Zymeworks CallCo ULC (“CallCo”) and Zymeworks ExchangeCo Ltd., (“ExchangeCo”) including a plan of arrangement included as Exhibit A to the Restated and Amended Transaction Agreement (the “Plan of Arrangement”).

Research, Collaboration and Licensing Agreements - 2016 Collaboration Agreement with Daiichi Sankyo, Co., Ltd. (Details) $ in Thousands	12 Months Ended			78 Months Ended
	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jun. 06, 2022 antibody
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 105,965	$ 76,304	$ 76,012
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Cross License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody					1
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Technology Access Fee \| Cross License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				$ 2,000
Daiichi Sankyo, Co., Ltd. (“Daiichi Sankyo”): \| Research, Development, Commercial License Option Milestone \| Cross License Agreement \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				$ 4,500

- Definition

+ References

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+ Details

Income Taxes

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Income Taxes

Loss before provision for income taxes was as follows:


	Year Ended December 31,
	2025
United States	$	(16,809)
Foreign	(62,945)
Loss before income taxes	$	(79,754)

Income tax expense is comprised of the following:


	Year Ended December 31,
	2025
Current tax provision:
Federal	482
State	(15)
Foreign	(898)
Total current tax expense	(431)

Deferred tax provision:
Federal	(845)
State	—
Foreign	(100)
Total deferred tax expense	(945)

Provision for income taxes	$	(1,376)


	Year Ended December 31,
	2024		2023
Current income tax expense	$	(5,393)	$	(189)
Deferred income tax (expense) recovery	(691)		757
Income tax (expense) recovery	$	(6,084)	$	568

Current income tax expense for the years ended December 31, 2025, 2024 and 2023 arose from the operations of the Company and its wholly owned subsidiaries in Canada, in the United States, in Ireland and in Singapore, as well as withholding taxes paid by the Company abroad in 2025, 2024 and 2023.


	Year Ended December 31,
	2025
	$	Percent
U.S. Federal statutory income tax rate	16,748	21.0	%
State & local income tax, net of federal income tax effect (1)	(15)	—	%
Foreign tax effects
Canada
Tax rate differential	(3,980)	(5.0)	%
Provincial tax rate differential	7,642	9.6	%
Changes in valuation allowance	(15,682)	(19.7)	%
Effect of cross-border laws	(1,921)	(2.4)	%
SR&ED Tax Credits	2,971	3.7	%
Stock Based Compensation	(4,065)	(5.1)	%
Other	91	0.1	%
United Kingdom
Stock Based Compensation	1,047	1.3	%
Other	(16)	—	%
Other foreign jurisdictions	(208)	(0.2)	%
Enactment of new tax laws	—	—	%
Effect of cross-border laws
Foreign Base Company Income	(2,006)	(2.5)	%
Other	—	—	%
Tax Credits	635	0.8	%
Changes in valuation allowance	(3,237)	(4.1)	%
Non-taxable or non-deductible items	(122)	(0.2)	%
Changes in unrecognized tax benefits	(97)	(0.1)	%
Other	839	1.1	%
Effective Income Tax Rate	(1,376)	(1.7)	%

(1) State taxes in New York, New Jersey, and Texas made up the majority of the tax effect in this category for the year ended December, 31 2025.


	Year Ended December 31,
	2024		2023
Computed taxes at United States statutory income tax rate	$	24,466	$	25,041
Non-deductible expenses	(10,508)		(2,696)
Difference between domestic and foreign tax rate	5,360		5,976
Adjustments to prior year	524		48,724
Change in valuation allowance	(28,882)		(78,668)
Change in recognition and measurement of tax positions	(38)		(14)
Changes due to SR&ED and research credits	3,102		2,661
Other	(108)		(456)
Income tax (expense) recovery	$	(6,084)	$	568

Deferred income tax assets and liabilities result from the temporary differences between the amounts of assets and liabilities recognized for financial statement and income tax purposes. The significant components of the deferred income tax assets and liabilities are as follows:


	December 31, 2025		December 31, 2024
Deferred tax assets:
Non-capital losses carried forward	$	199,946	$	177,660
Deferred revenue	4,596		10,852
Share issuance costs	666		1,360
Property and equipment	—		71
Intangible assets	5,271		4,539
Research and development deductions and credits	57,097		50,415
Stock options	7,724		8,388
Operating lease liability	4,657		4,761
Other	42		202
	$	279,999	$	258,248
Deferred tax liabilities:
Property and equipment	(243)		(174)
Operating lease right-of-use assets	(4,024)		(4,294)
Outside basis difference in foreign subsidiary	(2,414)		(2,429)
Stock options	—		(2,333)
Other	(182)		(176)
	$	(6,863)	$	(9,406)
	273,136		248,842
Less: valuation allowance	(274,457)		(249,218)
Net deferred tax (liabilities) assets	$	(1,321)	$	(376)
Deferred tax assets	$	4,707	$	4,385
Deferred tax liabilities	(6,028)		(4,761)
Net deferred tax (liabilities) assets	$	(1,321)	$	(376)

In evaluating the ability to realize the net deferred tax assets, all available positive and negative evidence was considered, including the Company's past operating results and the forecast of future market growth, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies. The change in the valuation allowance from December 31, 2024 to December 31, 2025 primarily relates to loss carryforward attributes sustained in the current reporting period that are not more-likely-than-not to be realized.

At December 31, 2025, the Company has net operating losses carried forward for tax purposes in Canada, which are available to reduce taxable income of future years of approximately $737.0 million (December 31, 2024: $658.0 million) expiring commencing 2035 through 2045.

At December 31, 2025, the Company also has unclaimed tax deductions for scientific research and experimental development expenditures of approximately $121.0 million (December 31, 2024: $108.6 million) available to reduce taxable income of future years in Canada, with no expiry. At December 31, 2025, the Company has approximately $28.0 million (December 31, 2024: $25.0 million) of investment tax credits available to offset Canadian federal and provincial taxes payable expiring commencing in 2039 through 2045, and has approximately $1.1 million (December 31, 2024: $0.9 million) of research tax credits available to offset U.S. federal taxes payable expiring commencing in 2042 through 2045.

A reconciliation of total unrecognized tax benefits for the years ended December 31, 2025, 2024, and 2023 are as follows:


	Year Ended December 31,
	2025		2024		2023
Balance, beginning of year	$	3,115	$	3,077	$	3,063
Gross increases related to prior year tax positions	2,364		—		—
Gross decreases to tax positions in prior periods	—		—		—
Gross increases to current period tax positions	97		38		14
Gross decreases due to settlements with taxing authorities	—		—		—
Gross decreases due to statute of limitations lapse	—		—		—
Balance, end of year	$	5,576	$	3,115	$	3,077

Included in the balance of unrecognized tax benefits at December 31, 2025, 2024 and 2023 are potential benefits of nil that, if recognized, would affect the effective tax rate on income from continuing operations. Recognition of these potential benefits would result in a deferred tax asset in the form of net operating loss carry-forward, which would be subject to a valuation allowance based on conditions existing at the reporting date.

The Company recognizes interest expense and penalties related to unrecognized tax benefits within the provision for income tax expense on the consolidated statements of loss and comprehensive loss.

The Company currently files income tax returns in Canada, the United States, the United Kingdom, Ireland and Singapore, the jurisdictions in which the Company believes that it is subject to tax. Further, while the statute of limitations in each jurisdiction where an income tax return has been filed generally limits the examination period, as a result of loss carry-forwards, the limitation period for examination generally does not expire until several years after the loss carry-forwards are utilized. Other than routine audits by tax authorities for tax credits and tax refunds that the Company has claimed, management is not aware of any other material income tax examination currently in progress by any taxing jurisdiction. Tax years ranging from 2006 to 2025 remain subject to Canadian income tax examinations. Tax years ranging from 2022 to 2025 remain subject to U.S. income tax examinations. Tax years ranging from 2022 to 2025 remain subject to United Kingdom income tax examinations. Tax years 2023 to 2025 remains subject to Ireland and Singapore income tax examinations.

The amounts of cash income taxes paid by the Company were as follows:


	Year Ended December 31,
	2025
Federal	$	213
State	17
Foreign
Ireland	72
United Kingdom	1,030
All other foreign	18
Income taxes, net of amounts refunded	$	1,350

- Definition

The entire disclosure for income tax.

+ References

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+ Details

Business Segments (Tables)

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment

Revenue and net income for the Company's biotherapeutics segment are shown below:


	Year Ended December 31,
	2025		2024		2023

Revenue from research and development collaborations	$	105,965	$	76,304	$	76,012

Segment expenses:
Zanidatamab	(1,828)		11,939		44,751
ZW171	9,672		7,151		10,686
ZW191	12,129		8,379		11,714
ZW220	2,922		13,824		1,585
ZW251	11,304		8,103		686
Zanidatamab zovodotin	364		6,595		8,046
Expense for other preclinical and research programs	31,114		17,389		7,819
Salaries and benefits	51,023		50,678		49,931
Other research and development expense	20,581		17,949		19,128
Other general and administrative expense	25,474		29,522		40,823

Total segment expenses	162,755		171,529		195,169

Segment loss	(56,790)		(95,225)		(119,157)

Reconciling items:
Depreciation and amortization	(7,725)		(8,684)		(10,164)
Stock-based compensation expense	(28,034)		(17,792)		(8,102)
Change in contingent consideration	—		1,878		(630)
Impairment	—		(17,287)		—
Interest income	13,354		19,941		19,705
Other income (expense), net	(559)		558		(894)
Income tax (expense) recovery, net	(1,376)		(6,084)		568

Net (loss) income	$	(81,130)	$	(122,695)	$	(118,674)

Summary of Significant Accounting Policies - Summary of Estimated Useful Lives (Details)	Dec. 31, 2025
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment useful lives	3 years
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment useful lives	3 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment useful lives	5 years
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment useful lives	7 years

Research, Collaboration and Licensing Agreements - 2020 Research and License Agreement with Merck (Details) - Merck Sharp and Dohme Research Ltd. $ in Millions	Jul. 31, 2020 USD ($) antibody
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of antibodies \| antibody	3
Maximum exercise fees and milestone payments	$ 419.3
Maximum milestone payments and tiered royalties	$ 502.5

Business Segments - Additional Information (Details)	12 Months Ended
Business Segments - Additional Information (Details)	Dec. 31, 2025 segment
Segment Reporting [Abstract]
Number of reportable segments	1

Consolidated Statements of Changes in Stockholders’ Equity - USD ($) $ in Thousands	Total	Preferred stock	Exchangeable shares	Common stock	Accumulated deficit	Accumulated other comprehensive loss	Additional paid-in capital
Beginning balance (in shares) at Dec. 31, 2022		1	1,424,533	63,059,501
Beginning balance at Dec. 31, 2022	$ 492,956	$ 0	$ 20,442	$ 886,322	$ (558,763)	$ (6,659)	$ 151,614
Stockholders' Equity
Issuance of common stock on exercise of stock options (note 10e) (in shares)				641,129
Issuance of common stock on exercise of stock options (note 10e)	5,222			$ 6,958			(1,736)
Issuance of common stock through employee stock purchase plan (note 10f) (in shares)				111,911
Issuance of common stock through employee stock purchase plan (note 10f)	955			$ 955
Issuance of common stock upon vesting of restricted stock units ("RSUs") (note 10e) ("RSUs") (in shares)				100,949
Issuance of common stock upon vesting of RSUs (note 10e)	0			$ 1,887			(1,887)
Issuance of common stock upon exercise of pre-funded warrants (note 10d) (in shares)				2,079,193
Issuance of common stock upon exercise of pre-funded warrants (note 10d)	0			$ 63,775			(63,775)
Issuance of common stock for retracted exchangeable shares (in shares)			(773,314)	773,314
Issuance of common stock for retracted exchangeable shares	0		$ (11,097)	$ 11,097
Issuance of common stock in connection with At-The-Market ("ATM") sale (note 10a) (in shares)				3,350,000
Issuance of common stock in connection with At-The-Market ("ATM") sale (note 10a)	26,233			$ 26,233
Private placement for issuance of common stock (note 10a and 10d)	49,862						49,862
Stock-based compensation	8,196						8,196
Net (loss) income	(118,674)				(118,674)
Other comprehensive income (loss)	56					56
Ending balance (in shares) at Dec. 31, 2023		1	651,219	70,115,997
Ending balance at Dec. 31, 2023	464,806	$ 0	$ 9,345	$ 997,227	(677,437)	(6,603)	142,274
Stockholders' Equity
Issuance of common stock on exercise of stock options (note 10e) (in shares)				959,906
Issuance of common stock on exercise of stock options (note 10e)	9,182			$ 13,952			(4,770)
Issuance of common stock through employee stock purchase plan (note 10f) (in shares)				128,232
Issuance of common stock through employee stock purchase plan (note 10f)	1,311			$ 1,311
Issuance of common stock upon vesting of restricted stock units ("RSUs") (note 10e) ("RSUs") (in shares)				225,004
Issuance of common stock upon vesting of RSUs (note 10e)	0			$ 1,971			(1,971)
Issuance of common stock for retracted exchangeable shares (in shares)			(80,582)	80,582
Issuance of common stock for retracted exchangeable shares	0		$ (1,157)	$ 1,157
Stock-based compensation	16,716						16,716
Purchase and retirement of common stock (10c) (in shares)				(2,545,402)
Purchase and retirement of common stock (10c)	(30,051)				(30,051)
Excise tax on repurchase of common stock	(152)				(152)
Net (loss) income	(122,695)				(122,695)
Other comprehensive income (loss)	(349)					(349)
Ending balance (in shares) at Dec. 31, 2024		1	570,637	68,964,319
Ending balance at Dec. 31, 2024	338,768	$ 0	$ 8,188	$ 1,015,618	(830,335)	(6,952)	152,249
Stockholders' Equity
Issuance of common stock on exercise of stock options (note 10e) (in shares)				1,742,689
Issuance of common stock on exercise of stock options (note 10e)	17,747			$ 27,308			(9,561)
Issuance of common stock through employee stock purchase plan (note 10f) (in shares)				139,976
Issuance of common stock through employee stock purchase plan (note 10f)	1,881			$ 1,881
Issuance of common stock upon vesting of restricted stock units ("RSUs") (note 10e) ("RSUs") (in shares)				560,620
Issuance of common stock upon vesting of RSUs (note 10e)	0			$ 5,269			(5,269)
Issuance of common stock upon exercise of pre-funded warrants (note 10d) (in shares)				5,086,480
Issuance of common stock upon exercise of pre-funded warrants (note 10d)	0			$ 49,862			(49,862)
Issuance of common stock for retracted exchangeable shares (in shares)			(17,453)	17,453
Issuance of common stock for retracted exchangeable shares	0		$ (250)	$ 250
Private placement for issuance of common stock (note 10a and 10d) (in shares)				415,000
Private placement for issuance of common stock (note 10a and 10d)	4,988			$ 4,988
Stock-based compensation	27,069						27,069
Purchase and retirement of common stock (10c) (in shares)				(2,288,124)
Purchase and retirement of common stock (10c)	(41,695)				(41,695)
Net (loss) income	(81,130)				(81,130)
Other comprehensive income (loss)	873					873
Ending balance (in shares) at Dec. 31, 2025		1	553,184	74,638,413
Ending balance at Dec. 31, 2025	$ 268,501	$ 0	$ 7,938	$ 1,105,176	$ (953,160)	$ (6,079)	$ 114,626

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Schedule of Estimated Useful Lives

The Company records depreciation using the straight-line method over the estimated useful lives of the property and equipment as follows:


Asset Class						Rate
Computer hardware						3 years
Office equipment						3 years
Furniture and fixtures						5 years
Laboratory equipment						7 years
Leasehold improvements						Shorter of the lease term or useful life

Schedule of Intangible Assets

The Company records amortization using the straight-line method over the estimated useful lives of the definite-lived intangible assets as follows:


Asset Class						Rate
Software						3 years
Licensing agreements						Shorter of the licensing term or useful life

Intangible assets consist of the following:


	December 31,
	2025		2024
Research licenses	$	14,936	$	14,936
Computer software	11,501		10,670
Intangible assets	26,437		25,606
Less accumulated amortization	(25,087)		(21,030)
Intangible assets, net	$	1,350	$	4,576

Stockholders' Equity - Additional Information (Details) - USD ($)									12 Months Ended			14 Months Ended	54 Months Ended
	Aug. 10, 2025	Jun. 26, 2025	Jul. 19, 2024	Dec. 28, 2023	Jun. 16, 2023	Oct. 13, 2022	Jun. 07, 2018	Jul. 14, 2006	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Oct. 19, 2023	Dec. 28, 2023	Nov. 16, 2025	Aug. 01, 2024	Oct. 12, 2022	Jun. 09, 2022	Jan. 05, 2022
Temporary Equity [Line Items]
Common stock, par value per share (in dollars per share)									$ 0.00001	$ 0.00001				$ 0.00001	$ 0.00001
Total shares authorized (in shares)									1,000,000,000
Common stock, shares authorized (in shares)									900,000,000	900,000,000
Preferred stock, shares authorized (in shares)									100,000,000	100,000,000
Preferred stock, par value (in dollars per share)									$ 0.00001	$ 0.00001
Preferred stock, shares issued (in shares)									1	1
Preferred stock, shares outstanding (in shares)									1	1
Common shares, issued (in shares)									74,638,413	68,964,319
Common shares, outstanding (in shares)									74,638,413	68,964,319
Exchangeable shares, shares outstanding (in shares)									553,184	570,637
Excise tax on share repurchases										$ 152,000
Class of warrant or right, number of securities called by each warrant or right (in shares)																0.001	0.001
Shares granted with respect to maximum fixed amount equal, percentage								20.00%
Options granted under original plan exercisable period									10 years
Number of shares available for grant (in shares)									5,023,809	5,196,630
Proceeds from stock options exercised									$ 16,904,000	$ 8,857,000	$ 5,006,000
Stock-based compensation									27,069,000	16,716,000	8,196,000
Derivative liability, classified stock options and ESPP									$ 887,000	$ 211,000	$ 630,000
Expected average option term									6 years 18 days	6 years	5 years 10 months 20 days
Option exercised intrinsic value									$ 14,152,000	$ 2,242,000	$ 758,000
Unamortized compensation expense related to unvested options									$ 13,051,000
Remaining unamortized compensation expense, weighted-average period									1 year 9 months 18 days
2024 Repurchase Program
Temporary Equity [Line Items]
Share repurchase program, authorized amount															$ 60,000,000
Treasury stock repurchased (in shares)									1,856,907	2,545,402
Treasury stock repurchased value									$ 29,997,000	$ 30,000,000
Commission expense on share repurchases									37,000	51,000
Excise tax on share repurchases									$ 0	$ 152,000
Retirement of treasury stock (in shares)									1,856,907	2,545,402
2025 Repurchase Program
Temporary Equity [Line Items]
Share repurchase program, authorized amount														$ 125,000
Treasury stock repurchased (in shares)									431,217
Treasury stock repurchased value									$ 11,188,000
Commission expense on share repurchases									9,000
Excise tax on share repurchases									$ 0
Retirement of treasury stock (in shares)									431,217
Treasury stock payable									$ 464,000
Additional paid-in capital
Temporary Equity [Line Items]
Stock-based compensation									$ 27,069,000	$ 16,716,000	8,196,000
Common stock
Temporary Equity [Line Items]
Number of common shares issued (in shares)						60,274,854
Exchangeable shares
Temporary Equity [Line Items]
Exchange of shares per the Redomiciliation (in shares)						1,424,533
Maximum
Temporary Equity [Line Items]
Expected average option term									10 years
Pre-Funded Warrant
Temporary Equity [Line Items]
Class of warrant or right, pre-funded (in shares)													13,668,482
Warrants issued to purchase shares (in shares)				13,668,482									13,668,482
Warrant exercise price (in dollars per share)				$ 0.0001									$ 0.0001
Warrants exercised during period (in shares)		5,086,521										8,581,961
Issuance of common shares upon exercise of pre-funded warrants (in shares)		5,086,480										8,581,868
Warrants outstanding (in shares)									0	5,086,521
Inducement Plan
Temporary Equity [Line Items]
Number of shares available for grant (in shares)			1,450,000						390,000	390,000
Number of common shares reserved for issuance (in shares)																		750,000
Number of additional shares authorized (in shares)			700,000
Restricted Stock Units (RSUs)
Temporary Equity [Line Items]
Nonvested award, cost not yet recognized, amount									$ 7,512,000
Nonvested award, cost not yet recognized, period for recognition									1 year 6 months 7 days
Compensation charge									$ 10,727,000	$ 5,813,000	3,369,000
Employee Stock
Temporary Equity [Line Items]
Percentage of discounted purchase price of average market price							85.00%
Employees Stock Purchase Plan
Temporary Equity [Line Items]
Compensation charge									498,000	370,000	$ 387,000
Total amount contributed by ESPP participants									$ 670,000	$ 577,000
Zymeworks BC Inc
Temporary Equity [Line Items]
Common shares, issued (in shares)																61,699,387
Common shares, outstanding (in shares)																61,699,387
Private Placement
Temporary Equity [Line Items]
Number of common shares issued (in shares)	415,000
Common stock, par value per share (in dollars per share)	$ 0.00001
Net proceeds from issuance	$ 4,988,000			$ 49,862,000
Class of warrant or right, pre-funded (in shares)				5,086,521
Warrants issued to purchase shares (in shares)				5,086,521									5,086,521
Warrants issued price per pre funded warrant (in dollars per share)				$ 9.8299									$ 9.8299
Issuance of common shares on exercise of warrants (note 10)				$ 50,000,000
2023 ATM Financing
Temporary Equity [Line Items]
Number of common shares issued (in shares)					3,350,000
Net proceeds from issuance					$ 26,233,000
Share issued, price per share (in dollars per share)					$ 8.12

Intangible Assets - Schedule of Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2025 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2026	$ 703
2027	490
2028	157
Thereafter	0
Intangible assets, net	$ 1,350

Other Income (Expense), net

12 Months Ended

Dec. 31, 2025

Other Income and Expenses [Abstract]

Other Income (Expense), net

Other income (expense), net consists of the following:


	Year ended December 31,
	2025		2024		2023
Foreign exchange (loss) gain	$	(610)	$	776	$	(1,185)
Other	51		(218)		291
	$	(559)	$	558	$	(894)

Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense on intangible assets	$ 4,056	$ 4,496	$ 2,702

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-18

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-11

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476153/220-40-55-24

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-12

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 40
-SubTopic 30
-Topic 350
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482640/350-30-55-40

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482686/350-30-45-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-6

+ Details

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2025

Stockholders' Equity Note [Abstract]

Schedule of Repurchase Agreements

The following table presents the Company’s 2024 Repurchase Program activity:


	Total number of shares purchased	Average price paid per share		Approximate value of shares purchased

Year Ended December 31, 2024	2,545,402	$	11.79	$	30,000
Year Ended December 31, 2025	1,856,907	$	16.15	$	29,997

The following table presents the Company’s 2025 Repurchase Program activity:


	Total number of shares purchased	Average price paid per share		Approximate value of shares purchased

Year Ended December 31, 2025	431,217	$	25.94	$	11,188

Schedule of RSU Activity

The following table summarizes the Company’s RSU activity under the New Plan:


	Number of RSUs	Weighted- average grant date fair value ($)
Outstanding, December 31, 2023	771,413	8.63
Granted	957,750	10.56
Vested and settled	(225,004)	8.76
Forfeited	(210,189)	10.75
Outstanding, December 31, 2024	1,293,970	9.69
Granted	1,398,697	14.29
Vested and settled	(560,620)	9.40
Forfeited	(184,463)	11.59
Outstanding, December 31, 2025	1,947,584	12.90

Schedule of Stock Options Granted

The following table summarizes the Company’s stock options granted in Canadian dollars under the Original Plan and the New Plan:


	Number of Options	Weighted- Average Exercise Price (C$)	Weighted- Average Exercise Price ($)	Weighted- Average Contractual Term (years)	Aggregate intrinsic value (C$)	Aggregate intrinsic value ($)
Outstanding, December 31, 2023	1,489,478	19.59	14.39	5.50	2,987	2,255
Granted	—	—	—
Expired	(58,902)	32.37	23.46
Exercised	(224,042)	11.23	8.20
Forfeited	(123,699)	21.85	16.11
Outstanding, December 31, 2024	1,082,835	20.36	14.15	4.73	6,485	4,509
Granted	—	—	—
Expired	(28,707)	39.94	28.75
Exercised	(444,397)	13.43	9.69
Forfeited	(37,619)	18.32	13.31
Outstanding, December 31, 2025	572,112	24.89	18.17	4.31	8,327	6,081
December 31, 2025
Exercisable	553,766	25.45	18.58	4.25	7,811	5,701
Vested and expected to vest	570,277	24.95	18.21	4.31	8,276	6,040

The following table summarizes the Company’s stock options granted in U.S. dollars under the New Plan and the Inducement Plan:


	Number of Options	Weighted- Average Exercise Price ($)	Weighted- Average Contractual Term (years)	Aggregate intrinsic value ($)
Outstanding, December 31, 2023	6,069,242	12.97	7.67	9,213
Granted	3,135,500	11.15
Expired	—	—
Exercised	(735,864)	9.57
Forfeited	(1,137,794)	16.34
Outstanding, December 31, 2024	7,331,084	12.01	7.97	30,459
Granted	2,467,225	14.21
Expired	(63,994)	30.59
Exercised	(1,298,292)	9.63
Forfeited	(619,746)	14.99
Outstanding, December 31, 2025	7,816,277	12.71	7.47	109,157
December 31, 2025
Exercisable	3,763,060	12.78	6.29	53,695
Vested and expected to vest	7,078,461	12.68	7.34	99,302

Schedule of Non-Vested Stock Option Activity

A summary of the non-vested stock option activity and related information of the Company’s stock options granted in Canadian dollars is as follows:


	Number of options	Weighted-average grant date fair value (C$)	Weighted- average grant date fair value (US$)
Non-vested, December 31, 2024	100,967	7.31	5.08
Options granted	—	—	—
Options vested	(72,760)	8.02	5.85
Options forfeited and cancelled	(9,861)	5.64	4.12
Non-vested, December 31, 2025	18,346	5.42	3.95

A summary of the non-vested stock option activity and related information of the Company’s stock options granted in U.S. dollars is as follows:


	Number of options	Weighted- average grant date fair value (US$)
Non-vested, December 31, 2024	4,147,288	6.65
Options granted	2,467,225	8.76
Options vested	(2,086,563)	6.72
Options forfeited and cancelled	(474,733)	6.36
Non-vested, December 31, 2025	4,053,217	7.84

Schedule of Stock-based Compensation Expense for Equity Classified Instruments

Stock-based compensation expense for equity classified instruments, as well as the financial statement impact of the amortization and periodic revaluation of liability classified instruments (note 2), are recorded in research and development expense and general and administration expense as follows:


	Year Ended December 31,
	2025		2024		2023

Research and development expense	$	12,849	$	8,382	$	2,404
General and administrative expense	$	14,687	$	9,041	$	5,316

Schedule of Estimated Fair Value of Stock Options Assumptions

The estimated fair value of stock options granted under the New Plan was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Year ended December 31,
	2025		2024		2023
Dividend yield	0	%	0	%	0	%
Expected volatility	63.1	%	64.5	%	68.1	%
Risk-free interest rate	4.32	%	4.04	%	3.94	%
Expected average life of options	6.05 years		6.00 years		5.89 years

The weighted-average Black-Scholes option pricing assumptions for liability classified stock options outstanding at December 31, 2025 and 2024 are as follows:


	December 31, 2025		December 31, 2024
Dividend yield	0	%	0	%
Expected volatility	55.3	%	45.8	%
Risk-free interest rate	2.56	%	2.90	%
Expected average option term	0.90 years		0.85 years
Number of liability classified stock options outstanding	64,402		272,330

Stockholders' Equity - Repurchase Program Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
2024 Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury stock repurchased (in shares)	1,856,907	2,545,402
Average price paid per share ( in usd per share)	$ 16.15	$ 11.79
Approximate value of shares purchased	$ 29,997	$ 30,000
2025 Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury stock repurchased (in shares)	431,217
Average price paid per share ( in usd per share)	$ 25.94
Approximate value of shares purchased	$ 11,188

- 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

Stockholders' Equity - Schedule of Estimated Fair Value of Stock Options Assumptions (Details) - shares	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	63.10%	64.50%	68.10%
Risk-free interest rate	4.32%	4.04%	3.94%
Expected average option term	6 years 18 days	6 years	5 years 10 months 20 days
Liability Classified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%
Expected volatility	55.30%	45.80%
Risk-free interest rate	2.56%	2.90%
Expected average option term	10 months 24 days	10 months 6 days
Number of liability classified stock options outstanding (in shares)	64,402	272,330

- 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

Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

The Company records amortization using the straight-line method over the estimated useful lives of the definite-lived intangible assets as follows:


Asset Class						Rate
Software						3 years
Licensing agreements						Shorter of the licensing term or useful life

Intangible assets consist of the following:


	December 31,
	2025		2024
Research licenses	$	14,936	$	14,936
Computer software	11,501		10,670
Intangible assets	26,437		25,606
Less accumulated amortization	(25,087)		(21,030)
Intangible assets, net	$	1,350	$	4,576

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

At December 31, 2025, amortization expense on capitalized intangible assets is estimated to be as follows for the next five years:


	Amortization expense
2026	$	703
2027	490
2028	157
Thereafter	—
	$	1,350

Research, Collaboration and Licensing Agreements - Jazz Collaboration Agreement (Details) - USD ($)		1 Months Ended		12 Months Ended
	Apr. 25, 2023	Dec. 31, 2022	Nov. 30, 2022	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Oct. 18, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contract liabilities				$ 17,000,000.0	$ 40,200,000
Research and development collaborations				105,965,000	76,304,000	$ 76,012,000
Contract liabilities				2,418,000	$ 25,588,000
License And Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration agreement expense						$ 20,100,000
License And Collaboration Agreement \| Jazz: \| Zanidatamab
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage interest in subsidiary sold	100.00%
Jazz: \| License And Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, maximum regulatory milestone payments							$ 500,000,000.0
Collaborative arrangement, maximum commercial milestone payments							$ 862,500,000
Contract liabilities				2,400,000
Jazz: \| License And Collaboration Agreement \| Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, royalty percentage							10.00%
Jazz: \| License And Collaboration Agreement \| Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, royalty percentage							20.00%
Jazz: \| Delivery of Licenses, Initial Technology Transfer and BTC Data Transfer \| License And Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from collaboration agreement		$ 325,000,000.0	$ 50,000,000.0
Contract liabilities							$ 375,000,000.0
Research and development collaborations		$ 325,000,000.0	$ 50,000,000.0
Jazz: \| Commercial and Development Milestones \| License And Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations				$ 0

Research, Collaboration and Licensing Agreements - 2016 Platform Technology Transfer and License Agreement with GSK (Details) - USD ($)		1 Months Ended		12 Months Ended			116 Months Ended
	Apr. 21, 2016	Jan. 31, 2025	Jul. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2025
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				$ 105,965,000	$ 76,304,000	$ 76,012,000
Glaxo Smith Kline Intellectual Property Development Ltd \| Milestone and Other Payments \| Maximum \| Eligible to Receive
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)	$ 1,100,000,000
Glaxo Smith Kline Intellectual Property Development Ltd \| Technology Access Fee \| Platform Technology Transfer and License Agreement \| Arrangement Other than Collaborative
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)							$ 6,000,000.0
Glaxo Smith Kline Intellectual Property Development Ltd \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)			$ 2,500,000
Glaxo Smith Kline Intellectual Property Development Ltd \| Research Milestone \| Maximum \| Eligible to Receive
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				35,000,000.0
Glaxo Smith Kline Intellectual Property Development Ltd \| Development Milestone \| Maximum \| Eligible to Receive
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				168,500,000
Glaxo Smith Kline Intellectual Property Development Ltd \| Commercial Sales Milestones \| Maximum \| Eligible to Receive
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)				867,000,000.0
Glaxo Smith Kline Intellectual Property Development Ltd \| Research, Development and Commercial Milestones \| Platform Technology Transfer and License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)							$ 0
GlaxoSmithKline Intellectual Property Development Ltd. (“GSK”): \| Milestone revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development collaborations (note 11)		$ 14,000,000.0		$ 14,000,000	$ 2,500,000	$ 0

IPR&D and Goodwill - Summary of Carrying Value of IPR&D, Net of Impairment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Net
ImpairmentOfIntangibleAssetIndefiniteLivedExcludingGoodwillStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag	AccumulatedAmortization
IPR&D
Acquired IPR&D
Acquired IPR&D, beginning balance	$ 20,700	$ 20,700	$ 20,700
Change during the period		0	0
Acquired IPR&D, ending balance		20,700	20,700
Accumulated Impairment
Beginning balance	(20,359)	(3,072)	(3,072)
Change during the period		(17,287)	0
Ending balance		(20,359)	(3,072)
Accumulated Amortization
Beginning balance	(341)	0	0
Change during the period		(341)	0
Ending balance		(341)	0
Net
Beginning balance	$ 0	17,628	17,628
Change during the period		(17,628)	0
Ending balance		$ 0	$ 17,628

IPR&D and Goodwill (Tables)

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Carrying Value of IPR&D, Net of Impairment

The following table summarizes the carrying value of IPR&D, net of impairment:


	Acquired IPR&D		Accumulated Impairment		Accumulated Amortization		Net
Balance at December 31, 2022	$	20,700	$	(3,072)	$	—	$	17,628
Change during the period	—		—		—		—
Balance at December 31, 2023	$	20,700	$	(3,072)	$	—	$	17,628
Change during the period	—		(17,287)		(341)		(17,628)
Balance at December 31, 2024	$	20,700	$	(20,359)	$	(341)	$	—

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) segment program
Schedule Of Accounting Policies [Line Items]
Description of payment terms	The Company's commercial partner is obligated to report its net product sales and resulting royalty due to the Company within 60 days from the end of each quarter.
Number of operating segments \| segment	1
Change In Clinical Trial Expense Accrual
Schedule Of Accounting Policies [Line Items]
Accrued expenses \| $	$ 6,676
Federal Tax Incentive
Schedule Of Accounting Policies [Line Items]
Number of operating programs \| program	2