0001104659-26-087545 | 10-Q | XBRL Viewer | Kiniksa Pharmaceuticals International PLC

Inventory

6 Months Ended

Jun. 30, 2026

4. Inventory

Inventory consisted of the following:


	June 30,		December 31,
	2026		2025
Raw materials	$	12,736	$	9,968
Semi-finished goods		34,196		29,399
Finished goods		29,025		20,555
Total inventory	$	75,957	$	59,922
Balance Sheet Classification:
Inventory	$	70,930	$	54,895
Other long-term assets		5,027		5,027
Total inventory	$	75,957	$	59,922

Income Taxes	6 Months Ended
Jun. 30, 2026
Income Taxes
Income Taxes	12. Income Taxes The Company’s income is subject to the enacted UK statutory corporate tax rate. The Company’s wholly owned United States subsidiaries, including Kiniksa Pharmaceuticals Corp. (“Kiniksa US”), are subject to federal and state income taxes in the United States. The Company’s wholly owned subsidiary Kiniksa Pharmaceuticals (UK), Ltd. (“Kiniksa UK”), and Kiniksa UK’s wholly owned subsidiaries, including Kiniksa Pharmaceuticals, GmbH (“Kiniksa Switzerland”) and Kiniksa UK’s Swiss branch office, are subject to taxation in their respective countries. Certain of the Company’s subsidiaries operate under cost plus intercompany arrangements. The Company recorded an income tax provision of $5,713 and $15,802 for the three and six months ended June 30, 2026, respectively. The provision for income taxes was driven primarily by income earned in Switzerland, UK and United States as well as uncertain tax positions offset in part by tax benefits related to share-based compensation, and United States federal and state research and development credits (“R&D Credits”). The Company recorded an income tax provision of $5,045 and $12,071 for the three and six months ended June 30, 2025, respectively. The provision for income taxes was driven primarily by income earned in Switzerland, UK and United States as well as uncertain tax positions offset in part by tax benefits from Foreign Derived Intangible Income (“FDII”) deduction and United States federal and state R&D Credits. Management regularly assesses the need for a valuation allowance on the Company’s deferred income tax assets. Valuation allowances require an assessment of both positive and negative evidence when determining whether it is more likely than not that the Company will be able to recover its deferred tax assets. Such assessment is required on a jurisdiction-by-jurisdiction basis. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. The Company maintains a valuation allowance on the full amount of the Kiniksa Switzerland deferred tax assets. There are no material deferred tax assets in the jurisdictions outside the United States, UK and Switzerland.

Income Taxes

6 Months Ended

Jun. 30, 2026

Income Taxes

Income Taxes

12. Income Taxes

The Company’s income is subject to the enacted UK statutory corporate tax rate. The Company’s wholly owned United States subsidiaries, including Kiniksa Pharmaceuticals Corp. (“Kiniksa US”), are subject to federal and state income taxes in the United States. The Company’s wholly owned subsidiary Kiniksa Pharmaceuticals (UK), Ltd. (“Kiniksa UK”), and Kiniksa UK’s wholly owned subsidiaries, including Kiniksa Pharmaceuticals, GmbH (“Kiniksa Switzerland”) and Kiniksa UK’s Swiss branch office, are subject to taxation in their respective countries. Certain of the Company’s subsidiaries operate under cost plus intercompany arrangements.

The Company recorded an income tax provision of $5,713 and $15,802 for the three and six months ended June 30, 2026, respectively. The provision for income taxes was driven primarily by income earned in Switzerland, UK and United States as well as uncertain tax positions offset in part by tax benefits related to share-based compensation, and United States federal and state research and development credits (“R&D Credits”).

The Company recorded an income tax provision of $5,045 and $12,071 for the three and six months ended June 30, 2025, respectively. The provision for income taxes was driven primarily by income earned in Switzerland, UK and United States as well as uncertain tax positions offset in part by tax benefits from Foreign Derived Intangible Income (“FDII”) deduction and United States federal and state R&D Credits.

Management regularly assesses the need for a valuation allowance on the Company’s deferred income tax assets. Valuation allowances require an assessment of both positive and negative evidence when determining whether it is more likely than not that the Company will be able to recover its deferred tax assets. Such assessment is required on a jurisdiction-by-jurisdiction basis. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. The Company maintains a valuation allowance on the full amount of the Kiniksa Switzerland deferred tax assets. There are no material deferred tax assets in the jurisdictions outside the United States, UK and Switzerland.

- Definition

The entire disclosure for income tax.

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+ Details

Segment Information and Geographic Data - Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Information and Geographic Data
Revenue	$ 243,600	$ 156,797	$ 457,866	$ 294,582
United States
Segment Information and Geographic Data
Revenue			457,184	294,102
United Kingdom
Segment Information and Geographic Data
Revenue			$ 682	$ 480
Pharmaceutical
Segment Information and Geographic Data
Revenue	243,600	156,797
Pharmaceutical \| United States
Segment Information and Geographic Data
Revenue	243,116	156,506
Pharmaceutical \| United Kingdom
Segment Information and Geographic Data
Revenue	$ 484	$ 291

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

Commitments and Contingencies	6 Months Ended
Jun. 30, 2026
Commitments and Contingencies
Commitments and Contingencies	13. Commitments and Contingencies License Agreements The Company has entered into license agreements with various parties under which it is obligated to make contingent and non-contingent payments (see Note 10). Manufacturing Commitments The Company has a supply agreement with Regeneron pursuant to which the Company may order both clinical and commercial product (see Note 10). In June 2024, the Company entered into a Master Services Agreement and a Product Specific Agreement with Samsung Biologics Co., Ltd. as part of its technology transfer of the manufacturing process for ARCALYST drug substance. The Company has additionally entered into agreements with several contract development and manufacturing organizations to provide the Company with preclinical and clinical trial materials for its non-ARCALYST assets. As of June 30, 2026, the Company had committed to minimum purchase commitments under all of these agreements totaling $205,826, of which $118,532 is due within one year. The Company issued termination notices to contract development and manufacturing organizations in February 2025 to terminate the clinical supply agreements for the production of abiprubart. During the three months ended March 31, 2025, the Company recorded and paid $2,500 in research and development expenses because of these terminations. The Company does not expect to incur any additional expenses because of these terminations. Performance Cash Awards Beginning in the second quarter of 2025, the Company began granting cash awards (“Performance Cash Awards”) to certain eligible employees pursuant to the 2018 Plan, which were eligible to be received upon the achievement of certain specified development and regulatory milestones and that are subject to earnout percentages based upon the date of applicable milestone achievement. As of June 30, 2026, the Company estimates the future cash payments under such Performance Cash Awards to be $24,852 if the milestones are achieved at target. The Performance Cash Awards will be recognized when the applicable milestones are deemed probable of achievement with a cumulative catch-up and recognized over the remaining term. The Company has not deemed any of the Performance Cash Award development or regulatory milestones as probable as of June 30, 2026, and no expense has been recognized related to such awards. Indemnification Agreements The Company is not aware of any claims under indemnification arrangements that are expected to have a material effect on its financial position, results of operations or cash flows, and it has not accrued any liabilities related to such obligations in its condensed consolidated financial statements as of June 30, 2026 or December 31, 2025. Legal Proceedings The Company is not party to any material litigation and does not have contingency reserves established for any litigation liabilities.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2026

Commitments and Contingencies

Commitments and Contingencies

13. Commitments and Contingencies

License Agreements

The Company has entered into license agreements with various parties under which it is obligated to make contingent and non-contingent payments (see Note 10).

Manufacturing Commitments

The Company has a supply agreement with Regeneron pursuant to which the Company may order both clinical and commercial product (see Note 10). In June 2024, the Company entered into a Master Services Agreement and a Product Specific Agreement with Samsung Biologics Co., Ltd. as part of its technology transfer of the manufacturing

process for ARCALYST drug substance. The Company has additionally entered into agreements with several contract development and manufacturing organizations to provide the Company with preclinical and clinical trial materials for its non-ARCALYST assets. As of June 30, 2026, the Company had committed to minimum purchase commitments under all of these agreements totaling $205,826, of which $118,532 is due within one year.

The Company issued termination notices to contract development and manufacturing organizations in February 2025 to terminate the clinical supply agreements for the production of abiprubart. During the three months ended March 31, 2025, the Company recorded and paid $2,500 in research and development expenses because of these terminations. The Company does not expect to incur any additional expenses because of these terminations.

Performance Cash Awards

Beginning in the second quarter of 2025, the Company began granting cash awards (“Performance Cash Awards”) to certain eligible employees pursuant to the 2018 Plan, which were eligible to be received upon the achievement of certain specified development and regulatory milestones and that are subject to earnout percentages based upon the date of applicable milestone achievement. As of June 30, 2026, the Company estimates the future cash payments under such Performance Cash Awards to be $24,852 if the milestones are achieved at target. The Performance Cash Awards will be recognized when the applicable milestones are deemed probable of achievement with a cumulative catch-up and recognized over the remaining term. The Company has not deemed any of the Performance Cash Award development or regulatory milestones as probable as of June 30, 2026, and no expense has been recognized related to such awards.

Indemnification Agreements

The Company is not aware of any claims under indemnification arrangements that are expected to have a material effect on its financial position, results of operations or cash flows, and it has not accrued any liabilities related to such obligations in its condensed consolidated financial statements as of June 30, 2026 or December 31, 2025.

Legal Proceedings

The Company is not party to any material litigation and does not have contingency reserves established for any litigation liabilities.

Intangible Assets - Finite-lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Intangible Assets
Net	$ 14,750		$ 14,750		$ 15,250
Amortization expense	$ 250	$ 250	$ 500	$ 500
Regulatory milestone
Intangible Assets
Estimated life	20 years		20 years
Cost	$ 20,000		$ 20,000		20,000
Accumulated Amortization	5,250		5,250		4,750
Net	$ 14,750		$ 14,750		$ 15,250

- Definition

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+ Details

Inventory (Tables)

6 Months Ended

Jun. 30, 2026

Inventory

Schedule of inventory


	June 30,		December 31,
	2026		2025
Raw materials	$	12,736	$	9,968
Semi-finished goods		34,196		29,399
Finished goods		29,025		20,555
Total inventory	$	75,957	$	59,922
Balance Sheet Classification:
Inventory	$	70,930	$	54,895
Other long-term assets		5,027		5,027
Total inventory	$	75,957	$	59,922

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Manufacturing commitments
Non-cancelable purchase commitments	$ 205,826			$ 205,826
Amount of purchase commitment obligation due within one year	118,532			118,532
Research and development	40,899	$ 18,753		68,374	$ 38,078
Loss contingency
Loss contingency accrual				0
Abiprubart
Manufacturing commitments
Research and development			$ 2,500	0
PSOs
Long-term incentive plan
Performance cash award expense				0
2018 Plan
Long-term incentive plan
Estimated amount of cash award in the event performance goals are achieved	$ 24,852			$ 24,852

Product Revenue, Net

6 Months Ended

Jun. 30, 2026

Product Revenue, Net

Product Revenue, Net

3. Product Revenue, Net

The Company derives substantially all of its product revenue, net from sales of ARCALYST in the United States, which was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Product revenue, net	$	243,600	$	156,797	$	457,866	$	294,582

The following table summarizes balances and activity in each of the product revenue allowance and reserve categories for the six months ended June 30, 2026:


	Contractual		Government
	Adjustments		Rebates		Returns		Total
Balance at December 31, 2025	$	4,559	$	11,883	$	3,124	$	19,566
Current provisions relating to sales in the current year		19,469		17,395		1,012		37,876
Adjustments relating to prior years		(8)		(1,463)		(793)		(2,264)
Payments/returns relating to sales in the current year		(18,228)		(7,205)		—		(25,433)
Payments/returns relating to sales in the prior years		(4,551)		(7,522)		(131)		(12,204)
Balance at June 30, 2026	$	1,241	$	13,088	$	3,212	$	17,541

Total revenue-related reserves as of June 30, 2026 and December 31, 2025, included in the Company’s condensed consolidated balance sheets, are summarized as follows:


	June 30,		December 31,
	2026		2025
Components of accounts receivable	$	(1,160)	$	(831)
Components of other current liabilities		18,701		20,397
Total revenue-related reserves	$	17,541	$	19,566

Substantially all of the Company’s trade accounts receivable arise from product revenue in the United States due from the Company’s third party logistics provider.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

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

Nature of the Business and Basis of Presentation

6 Months Ended

Jun. 30, 2026

Nature of the Business and Basis of Presentation

Nature of the Business and Basis of Presentation

1. Nature of the Business and Basis of Presentation

Kiniksa Pharmaceuticals International, plc (the “Company”) is a biopharmaceutical company developing and commercializing novel therapies for diseases with unmet need, with a focus on cardiovascular indications. The Company’s portfolio of immune-modulating assets is based on strong biologic rationale or validated mechanisms, targets a spectrum of underserved cardiovascular and autoimmune conditions and offers the potential for differentiation.

The Company is subject to risks common to companies in the biopharmaceuticals industry including, but not limited to, commercialization of existing and new products, conducting clinical research and development, its current and future products and product candidates, risks from existing or new competition, protection of proprietary intellectual and other technology and compliance with United States and foreign regulations and approval requirements.

Unaudited Interim Condensed Consolidated Financial Information

The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information. The accompanying unaudited condensed consolidated financial statements do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 (the “2025 Form 10-K”). The Company’s accounting policies are described in the Notes to Consolidated Financial Statements included in the Company’s 2025 Form 10-K and updated, as necessary, in this report. The accompanying year-end condensed consolidated balance sheet was derived from audited financial statements but does not include all disclosures required by GAAP. The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2026 and the results of its operations for the three and six months ended June 30, 2026 and 2025, the changes in its shareholders’ equity for the three and six months ended June 30, 2026 and 2025 and its cash flows for the six months ended June 30, 2026 and 2025. The results for the three and six months ended June 30, 2026 are not necessarily indicative of results to be expected for the year ending December 31, 2026, any other interim periods or any future year or period.

Recently Issued Accounting Pronouncements

In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact of adopting ASU 2024-03 on its consolidated financial statements.

In September 2025, the FASB issued ASU 2025-06, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. ASU 2025-06 modernizes and simplifies the accounting for software development costs by establishing a single capitalization framework for all internally developed or acquired software, regardless of whether the software is intended for internal use, to be sold, or to be used in delivering products and services. The new guidance retains the concept of project stages but eliminates the historical distinction between internal-use software and software to be sold or marketed. ASU 2025-06 is effective for fiscal years beginning after December 15, 2027, including interim periods within those fiscal years, with early adoption permitted. The guidance is required to be applied prospectively, with optional retrospective or modified retrospective transition methods. The Company is currently evaluating the impact of ASU 2025-06 on its consolidated financial statements.

Recently Adopted Accounting Pronouncements

In September 2025, the FASB issued ASU 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606): Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract, which refines the scope of derivative accounting and clarifies the treatment of certain share-based noncash consideration in revenue contracts. The Company adopted this ASU in the first quarter of 2026, prospectively. The adoption of this ASU did not have a material effect on the Company’s consolidated financial statements.

Out-Licensing Agreements (Details) $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended
Out-Licensing Agreements (Details) $ in Thousands	Feb. 28, 2022 USD ($) item	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Sep. 30, 2022 USD ($) item	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Collaborative agreements
Revenue		$ 243,600	$ 156,797		$ 457,866	$ 294,582
Territory License - ARCALYST
Collaborative agreements
Upfront payments received	$ 12,000
Addition to transaction price					20,000		$ 20,000
Number of performance obligations in an agreement \| item	1
Term of agreement for royalty payments	12 years
Territory License - ARCALYST \| Maximum
Collaborative agreements
Payments to be received by the company upon the achievement of specified development, regulatory and sales milestones					50,000
Territory License - ARCALYST \| Location, Statement of Financial Position, Activity, Accrual [Axis]: us-gaap:ContractWithCustomerLiabilityNoncurrent
Collaborative agreements
Transaction price					31,811
Territory License - ARCALYST \| License and collaboration revenue
Collaborative agreements
Revenue		0	0		0	0
Worldwide License - Vixarelimab
Collaborative agreements
Number of performance obligations in an agreement \| item				4
Payments to be received by the company upon the achievement of specified development, regulatory and sales milestones				$ 600,000	570,000
Worldwide License - Vixarelimab \| License and collaboration revenue
Collaborative agreements
Revenue		$ 0	$ 0		$ 0	$ 0

Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2026

Intangible Assets

Schedule of intangible assets, net of accumulated amortization, impairment charges, and adjustments


		As of June 30, 2026								As of December 31, 2025
	Estimated				Accumulated								Accumulated
	life	Cost			Amortization			Net		Cost			Amortization			Net
Regulatory milestone	20 years	$	20,000		$	5,250		$	14,750	$	20,000		$	4,750		$	15,250

Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property and Equipment, Net
Total property and equipment	$ 10,114		$ 10,114		$ 9,173
Less: Accumulated depreciation	(7,539)		(7,539)		(7,230)
Total property and equipment, net	2,575		2,575		1,943
Depreciation expense	165	$ 13	309	$ 48
Furniture, fixtures and vehicles
Property and Equipment, Net
Total property and equipment	177		177		177
Computer hardware and software
Property and Equipment, Net
Total property and equipment	96		96		96
Leasehold improvements
Property and Equipment, Net
Total property and equipment	4,833		4,833		4,639
Lab equipment
Property and Equipment, Net
Total property and equipment	4,256		4,256		4,006
Construction in progress
Property and Equipment, Net
Total property and equipment	$ 752		$ 752		$ 255

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2026	Dec. 31, 2025
Class A ordinary shares
Ordinary shares, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Ordinary shares, shares issued (in shares)	48,244,934	45,659,424
Ordinary shares, shares outstanding (in shares)	48,244,934	45,659,424
Class B ordinary shares
Ordinary shares, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Ordinary shares, shares issued (in shares)	895,158	1,795,158
Ordinary shares, shares outstanding (in shares)	895,158	1,795,158
Class A1 ordinary shares
Ordinary shares, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Ordinary shares, shares issued (in shares)	12,781,964	12,781,964
Ordinary shares, shares outstanding (in shares)	12,781,964	12,781,964
Class B1 ordinary shares
Ordinary shares, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Ordinary shares, shares issued (in shares)	16,057,618	16,057,618
Ordinary shares, shares outstanding (in shares)	16,057,618	16,057,618

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Inventory
Raw materials	$ 12,736	$ 9,968
Semi-finished goods	34,196	29,399
Finished goods	29,025	20,555
Total inventory	75,957	59,922
Inventory	70,930	54,895
Location, Statement of Financial Position, Balance [Axis]: us-gaap:InventoryNet
Inventory
Inventory	70,930	54,895
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent
Inventory
Other long-term assets	$ 5,027	$ 5,027

Out-Licensing Agreements

6 Months Ended

Jun. 30, 2026

Out-Licensing Agreements

Out-Licensing Agreements

9. Out-Licensing Agreements

Genentech License Agreement

In the third quarter of 2022 (the “Genentech Effective Date”), the Company entered into a license agreement (the “Genentech License Agreement”) with Genentech, Inc. and F. Hoffmann-La Roche Ltd (collectively, “Genentech”), pursuant to which the Company granted Genentech exclusive worldwide rights to develop, manufacture and commercialize vixarelimab and related antibodies (each, a “Genentech Licensed Product”).

Under the terms of the Genentech License Agreement, the Company is eligible to receive a total of approximately $600,000 in contingent payments, including specified development, regulatory and sales-based milestones, before fulfilling the Company’s upstream financial obligations, of which approximately $570,000 remain as of June 30, 2026. The Company will also be eligible to receive tiered percentage royalties on a Genentech Licensed Product-by-Genentech Licensed Product basis ranging from low-double digits to mid-teens on annual net sales of each Genentech Licensed Product, subject to certain customary reductions, with an aggregate minimum floor, before fulfilling the Company’s upstream financial obligations. Royalties will be payable on a Genentech Licensed Product-by-Genentech Licensed Product and country-by-country basis until the latest to occur of the expiration of certain patents that cover a Genentech Licensed Product, the expiration of regulatory exclusivity for such Genentech Licensed Product, or the tenth anniversary of first commercial sale of such Genentech Licensed Product in such country.

Pursuant and subject to the terms of the Genentech License Agreement, Genentech has the exclusive worldwide right to conduct development and commercialization activities for Genentech Licensed Products at its sole cost. In 2024, the Company fulfilled its responsibility under the Genentech License Agreement with respect to completing its Phase 2b clinical trial assessing the efficacy, safety and tolerability of vixarelimab in reducing pruritus in prurigo nodularis.

Accounting for the Genentech License Agreement

As of the Genentech Effective Date, the Company identified the following performance obligations in the Genentech License Agreement: (i) the delivery of the exclusive license for vixarelimab; (ii) an initial drug supply delivery; (iii) a drug product resupply delivery; and (iv) completion of the Phase 2b clinical trial for vixarelimab.

The selling price of each performance obligation in the Genentech License Agreement was determined based on the Company’s standalone selling price with the objective of determining the price at which it would sell such an item if it were to be sold regularly on a standalone basis. The Company allocated the transaction price to each of the four performance obligations noted above, all of which were satisfied as of June 30, 2024.

The Company determined that all other variable considerations related to the future development and regulatory milestones, are deemed fully constrained and therefore excluded from the transaction price due to the high degree of uncertainty and risk associated with these potential payments, as the Company also determined that it could not assert that it was not probable that a significant reversal in the amount of cumulative revenue recognized would occur. The Company also determined that royalties and sales milestones relate solely to the license of intellectual property. Revenue related to these royalties and sales milestones will only be recognized when the associated sales occur, and relevant thresholds are met, under the sales or usage-based royalty exception of Topic 606.

The Company did not recognize any collaboration revenue under the Genentech License Agreement during the three and six months ended June 30, 2026 and 2025. As of June 30, 2026, the Company had recognized the entire transaction price under the Genentech License Agreement as revenue.

Huadong Collaboration Agreement

In February 2022 (the “Effective Date”), the Company entered into a collaboration and license agreement (the “Huadong Collaboration Agreement”) with Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd. (“Huadong”), pursuant to which the Company granted Huadong exclusive rights to develop and commercialize ARCALYST in a territory, which currently includes the following countries: People’s Republic of China, Hong Kong SAR, Macao SAR,

Taiwan Region, Indonesia, The Philippines, Thailand, Bangladesh, Bhutan, Brunei, Burma, Cambodia, India, Laos, Malaysia, Maldives, Mongolia, Nepal, New Zealand, Sri Lanka, and Vietnam (collectively, the “Huadong Territory”). The Company otherwise retained its current rights to ARCALYST outside the Huadong Territory.

Under the Huadong Collaboration Agreement, the Company received a total upfront cash payment of $12,000 for the Huadong Territory license of ARCALYST. In 2024, following the achievement of a regulatory milestone under the Huadong Collaboration Agreement, Huadong became obligated to make an additional cash payment of $20,000 to the Company. The Company will be eligible to receive up to approximately $50,000 in contingent sales-based milestone payments for ARCALYST, all of which remain outstanding as of June 30, 2026. Huadong will also be obligated to pay the Company tiered percentage royalties ranging from the low-to-mid teens on annual net sales of ARCALYST in the Huadong Territory, subject to certain reductions tied to ARCALYST manufacturing costs and certain other customary reductions, with an aggregate minimum floor. Royalties will be payable on ARCALYST on a country-by-country or region-by-region basis until the later of (i) 12 years after the first commercial sale of ARCALYST in such country or region in the Huadong Territory, (ii) the date of expiration of the last valid patent claim of the Company’s patent rights or any joint collaboration patent rights that covers ARCALYST in such country or region in the Huadong Territory, and (iii) the expiration of the last regulatory exclusivity for ARCALYST in such country or region in the Huadong Territory.

Accounting for the Huadong Collaboration Agreement

As of the Effective Date, the Company identified one performance obligation in the Huadong Collaboration Agreement: the exclusive license for ARCALYST and clinical and commercial manufacturing obligations for ARCALYST products in the Huadong Territory. Huadong cannot exploit the value of the exclusive license for ARCALYST products in the Huadong Territory without receipt of supply as the exclusive license for ARCALYST products in the Huadong Territory does not convey to Huadong the right to manufacture and therefore the Company has combined the exclusive license for ARCALYST products in the Huadong Territory and the manufacturing obligations into one performance obligation.

The Company determined the transaction price at the inception of the Huadong Collaboration Agreement, which includes $12,000, consisting of the upfront payment. In 2024, the Company added $20,000 to the transaction price following the achievement of a regulatory milestone. The Company also includes an estimate of variable consideration associated with the clinical and commercial manufacturing supply of certain materials when those materials are shipped. The Company determined that any variable consideration related to development and regulatory milestones, sales milestones and royalties are deemed fully constrained and therefore excluded from the transaction price due to the high degree of uncertainty and risk associated with these potential payments, as the Company determined that it could not assert that it was probable that a significant reversal in the amount of cumulative revenue recognized will not occur. Royalties and sales milestones will be recognized as the Company delivers the commercial manufactured product to Huadong. Any changes in estimates may result in a cumulative catch-up based on the number of units of manufactured product delivered.

The Company recognizes revenue for the single performance obligation in the Huadong Collaboration Agreement consisting of the exclusive license for ARCALYST and clinical and commercial manufacturing obligations for ARCALYST products in the Huadong Territory at a point in time, upon which control of materials are transferred to Huadong for each delivery of the associated materials. The Company currently expects to recognize the revenue over the life of the agreement. This estimate considers the timing of development and commercial activities under the Huadong Collaboration Agreement and may be reduced or increased based on changes in the various activities.

The Company did not recognize any revenue under the Huadong Collaboration Agreement during the three and six months ended June 30, 2026 and 2025. As of June 30, 2026, $31,811 of the transaction price is recorded in non-current deferred revenue, based upon timing of anticipated future shipments.

The following table summarizes the Company’s contract liabilities in connection with license and collaboration agreements for the six months ended June 30, 2026:


	Balance at				Revenue				Balance at End
	Beginning of Period		Additions		Recognized		Reclassification		of Period
Six Months Ended June 30, 2026
Contract Liabilities:
Huadong ARCALYST	$	31,811	$	—	$	—	$	—	$	31,811

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenue:
Revenue	$ 243,600	$ 156,797	$ 457,866	$ 294,582
Costs and operating expenses:
Cost of goods sold	23,572	18,603	44,368	36,471
Collaboration expenses	88,069	52,418	163,646	96,208
Research and development	40,899	18,753	68,374	38,078
Selling, general and administrative	63,866	46,863	125,017	90,393
Total operating expenses	216,406	136,637	401,405	261,150
Income from operations	27,194	20,160	56,461	33,432
Other income, net	3,951	2,717	7,365	5,010
Income before income taxes	31,145	22,877	63,826	38,442
Provision for income taxes	(5,713)	(5,045)	(15,802)	(12,071)
Net income	$ 25,432	$ 17,832	$ 48,024	$ 26,371
Net income per share attributable to ordinary shareholders, basic	$ 0.33	$ 0.24	$ 0.62	$ 0.36
Net income per share attributable to ordinary shareholders, diluted	$ 0.3	$ 0.23	$ 0.58	$ 0.34
Weighted average ordinary shares outstanding, basic	77,577,675	73,438,530	77,050,036	73,041,920
Weighted average ordinary shares outstanding, diluted	83,398,051	77,942,082	82,902,904	76,984,393
Comprehensive income
Net income	$ 25,432	$ 17,832	$ 48,024	$ 26,371
Other comprehensive income (loss)
Unrealized gain (loss) on short-term investments and currency translation adjustments, net of tax	(715)	112	(1,355)	110
Total other comprehensive income (loss)	(715)	112	(1,355)	110
Total comprehensive income	24,717	17,944	46,669	26,481
Product revenue, net
Revenue:
Revenue	$ 243,600	$ 156,797	$ 457,866	$ 294,582

Net Income per Share

6 Months Ended

Jun. 30, 2026

Net Income per Share

Net Income per Share

11. Net Income per Share

The rights, including the liquidation and dividend rights, of the holders of Class A, Class B, Class A1 and Class B1 ordinary shares are identical, except with respect to voting, transferability and conversion. As the liquidation and dividend rights are identical, losses are allocated on a proportionate basis and the resulting net income per share attributed to ordinary shareholders will, therefore, be the same for both Class A and Class B ordinary shares on an individual or combined basis.

Basic and diluted net income attributable to ordinary shareholders was calculated as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Numerator:
Net income attributable to ordinary shareholders	$	25,432	$	17,832	$	48,024	$	26,371
Denominator:
Weighted average ordinary shares outstanding—basic		77,577,675		73,438,530		77,050,036		73,041,920
Effect of dilutive securities
Options to purchase ordinary shares		4,576,481		3,504,516		4,585,743		3,105,795
Unvested RSUs		1,044,790		924,675		1,087,832		780,562
Unvested PSUs		199,105		74,362		179,293		56,116
Weighted average ordinary shares outstanding—diluted		83,398,051		77,942,082		82,902,904		76,984,393

Basic net income per share	$	0.33	$	0.24	$	0.62	$	0.36
Diluted net income per share	$	0.30	$	0.23	$	0.58	$	0.34

For the three and six months ended June 30, 2026 and 2025, diluted earnings per share includes the assumed exercise of dilutive options and the assumed issuance of ordinary shares for unvested RSUs and PSUs for which the market or performance condition has been met as of the date of determination, using the treasury stock method unless the effect is anti-dilutive. The treasury stock method assumes that proceeds, including cash received from the exercise of employee share options and the average unrecognized compensation expense for unvested share-based compensation awards, would be used to purchase the Company’s ordinary shares at the average market price during the period.

The Company excluded the following potential ordinary shares, presented based on amounts outstanding at each period end, from the computation of diluted EPS attributable to ordinary shareholders for the periods indicated because including them would have had an anti-dilutive effect:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Share options to purchase ordinary shares		883,520		3,026,168		1,485,845		3,804,284
Unvested RSUs		32,004		62,701		324,259		512,753
Total anti-dilutive shares		915,524		3,088,869		1,810,104		4,317,037

PSUs and PSOs that are outstanding and contain performance-based or market-based vesting criteria for which the performance or market conditions have not been met are excluded from the presentation of common stock equivalents outstanding in the table above.

License and Acquisition Agreements - Biogen Asset Purchase Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
License and Acquisition Agreements
Research and development	$ 40,899	$ 18,753	$ 68,374	$ 38,078
Other research and discovery related arrangements
License and Acquisition Agreements
Research and development	$ 6,520	$ 30	$ 6,520	$ 44

Share-Based Compensation - Market and Performance-Based Shares Units (Details)	6 Months Ended
	Jun. 30, 2026 $ / shares shares
Unvested RSUs
Share-Based Compensation
Weighted average grant date fair values \| $ / shares	$ 47.6
PSUs Granted	358,019
PSUs Vested	358,289
Number of shares
Beginning of the period	2,074,095
Granted	358,019
Vested	(358,289)
Forfeited	(220,211)
End of the period	1,853,614
Weighted Average Grant Date Fair Value
Beginning of the period \| $ / shares	$ 23.09
Granted \| $ / shares	47.6
Vested \| $ / shares	17.14
Forfeited \| $ / shares	25.34
End of the period \| $ / shares	$ 28.71
Unvested PSUs
Share-Based Compensation
Service period	3 years
Weighted average grant date fair values \| $ / shares	$ 59.39
PSUs Granted	184,771
Number of shares
Beginning of the period	415,307
Granted	184,771
Forfeited	(19,308)
End of the period	580,770
Weighted Average Grant Date Fair Value
Beginning of the period \| $ / shares	$ 27.25
Granted \| $ / shares	59.39
Forfeited \| $ / shares	27.64
End of the period \| $ / shares	$ 37.46

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Cash flows from operating activities:
Net income	$ 48,024	$ 26,371
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization expense	940	703
Share-based compensation expense	21,692	16,624
Non-cash lease expense	2,005	1,759
Net amortization of premiums and accretion of discounts on short-term investments	1,395	(589)
Net gain on disposal of property and equipment	(32)	(24)
Deferred income taxes	7,184	5,637
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(5,523)	(12,195)
Accounts receivable, net	(7,896)	9,814
Inventory	(16,035)	(21,817)
Other long-term assets	374	1,975
Accounts payable	10,267	6,992
Accrued expenses, accrued collaboration expenses and other current liabilities	20,744	9,502
Operating lease liabilities	(1,151)	(1,777)
Other long-term liabilities	15,406	7,439
Net cash provided by operating activities	97,394	50,414
Cash flows from investing activities:
Purchases of property and equipment	(824)	(264)
Purchases of short-term investments	(287,031)	(129,793)
Proceeds from the maturities of short-term investments	182,359	74,633
Net cash used in investing activities	(105,496)	(55,424)
Cash flows from financing activities:
Proceeds from issuance of Class A ordinary shares under incentive award plans and employee share purchase plan	23,967	15,925
Payments in connection with ordinary shares tendered for employee tax obligations	(5,784)	(2,459)
Net cash provided by financing activities	18,183	13,466
Net increase in cash and cash equivalents	10,081	8,456
Cash and cash equivalents at beginning of period	165,596	183,581
Cash and cash equivalents at end of period	175,677	192,037
Supplemental information:
Cash paid for income taxes	9	3,009
Supplemental disclosure of non-cash investing and financing activities:
Change in right-of-use asset as a result of new, modified, and terminated leases	551	1,687
Additions to property and equipment included in accrued expenses and other liabilities	$ 199	$ 338

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2026
Summary of Significant Accounting Policies
Unaudited Interim Consolidated Financial Information	Unaudited Interim Condensed Consolidated Financial Information The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information. The accompanying unaudited condensed consolidated financial statements do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 (the “2025 Form 10-K”). The Company’s accounting policies are described in the Notes to Consolidated Financial Statements included in the Company’s 2025 Form 10-K and updated, as necessary, in this report. The accompanying year-end condensed consolidated balance sheet was derived from audited financial statements but does not include all disclosures required by GAAP. The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2026 and the results of its operations for the three and six months ended June 30, 2026 and 2025, the changes in its shareholders’ equity for the three and six months ended June 30, 2026 and 2025 and its cash flows for the six months ended June 30, 2026 and 2025. The results for the three and six months ended June 30, 2026 are not necessarily indicative of results to be expected for the year ending December 31, 2026, any other interim periods or any future year or period.
Recently Issued and Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact of adopting ASU 2024-03 on its consolidated financial statements. In September 2025, the FASB issued ASU 2025-06, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. ASU 2025-06 modernizes and simplifies the accounting for software development costs by establishing a single capitalization framework for all internally developed or acquired software, regardless of whether the software is intended for internal use, to be sold, or to be used in delivering products and services. The new guidance retains the concept of project stages but eliminates the historical distinction between internal-use software and software to be sold or marketed. ASU 2025-06 is effective for fiscal years beginning after December 15, 2027, including interim periods within those fiscal years, with early adoption permitted. The guidance is required to be applied prospectively, with optional retrospective or modified retrospective transition methods. The Company is currently evaluating the impact of ASU 2025-06 on its consolidated financial statements. Recently Adopted Accounting Pronouncements In September 2025, the FASB issued ASU 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606): Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract, which refines the scope of derivative accounting and clarifies the treatment of certain share-based noncash consideration in revenue contracts. The Company adopted this ASU in the first quarter of 2026, prospectively. The adoption of this ASU did not have a material effect on the Company’s consolidated financial statements.

Out-Licensing Agreements - Contract Assets and Liabilities (Details) $ in Thousands	Jun. 30, 2026 USD ($)
Contract Liabilities:
Balance at Beginning of Period	$ 31,811
Balance at End of Period	31,811
Huadong ARCALYST
Contract Liabilities:
Balance at Beginning of Period	31,811
Balance at End of Period	$ 31,811

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 175,677	$ 165,596
Short-term investments	350,251	248,478
Accounts receivable, net	23,490	15,594
Inventory	70,930	54,895
Prepaid expenses and other current assets	48,285	42,614
Total current assets	668,633	527,177
Property and equipment, net	2,575	1,943
Operating lease right-of-use assets	8,353	9,807
Other long-term assets	10,834	11,307
Intangible asset, net	14,750	15,250
Deferred tax assets	190,965	198,149
Total assets	896,110	763,633
Current liabilities:
Accounts payable	12,404	2,028
Accrued collaboration expenses	88,049	70,015
Accrued expenses	46,730	42,020
Operating lease liabilities	4,012	2,987
Other current liabilities	20,052	22,134
Total current liabilities	171,247	139,184
Non-current liabilities:
Non-current deferred revenue	31,811	31,811
Non-current operating lease liabilities	4,885	6,510
Other long-term liabilities	34,018	18,522
Total liabilities	241,961	196,027
Commitments and contingencies (Note 13)
Shareholders' equity:
Additional paid-in capital	1,069,622	1,029,748
Accumulated other comprehensive loss	(1,380)	(25)
Accumulated deficit	(414,114)	(462,138)
Total shareholders' equity	654,149	567,606
Total liabilities and shareholders' equity	896,110	763,633
Class A ordinary shares
Shareholders' equity:
Ordinary shares value	12	12
Class B ordinary shares
Shareholders' equity:
Ordinary shares value	1	1
Class A1 ordinary shares
Shareholders' equity:
Ordinary shares value	4	4
Class B1 ordinary shares
Shareholders' equity:
Ordinary shares value	$ 4	$ 4

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Ordinary Shares	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Total
Balance at the beginning of the period at Dec. 31, 2024	$ 20	$ 959,722	$ (163)	$ (521,143)	$ 438,436
Balance at the beginning of the period (in shares) at Dec. 31, 2024	72,516,059
Changes in equity
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan		2,768			2,768
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan (in shares)	281,273
Share-based compensation expense		7,748			7,748
Unrealized gain (loss) on short-term investments and currency translation adjustments			(2)		(2)
us-gaap:NetIncomeLoss				8,539	8,539
Balance at the end of the period at Mar. 31, 2025	$ 20	970,238	(165)	(512,604)	457,489
Balance at the end of the period (in shares) at Mar. 31, 2025	72,797,332
Balance at the beginning of the period at Dec. 31, 2024	$ 20	959,722	(163)	(521,143)	438,436
Balance at the beginning of the period (in shares) at Dec. 31, 2024	72,516,059
Changes in equity
Unrealized gain (loss) on short-term investments and currency translation adjustments					110
us-gaap:NetIncomeLoss					26,371
Balance at the end of the period at Jun. 30, 2025	$ 21	989,811	(53)	(494,772)	495,007
Balance at the end of the period (in shares) at Jun. 30, 2025	74,032,363
Balance at the beginning of the period at Mar. 31, 2025	$ 20	970,238	(165)	(512,604)	457,489
Balance at the beginning of the period (in shares) at Mar. 31, 2025	72,797,332
Changes in equity
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan	$ 1	10,697			10,698
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan (in shares)	1,235,031
Share-based compensation expense		8,876			8,876
Unrealized gain (loss) on short-term investments and currency translation adjustments			112		112
us-gaap:NetIncomeLoss				17,832	17,832
Balance at the end of the period at Jun. 30, 2025	$ 21	989,811	(53)	(494,772)	495,007
Balance at the end of the period (in shares) at Jun. 30, 2025	74,032,363
Balance at the beginning of the period at Dec. 31, 2025	$ 21	1,029,748	(25)	(462,138)	567,606
Balance at the beginning of the period (in shares) at Dec. 31, 2025	76,294,164
Changes in equity
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan		6,073			6,073
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan (in shares)	395,296
Share-based compensation expense		10,056			10,056
Unrealized gain (loss) on short-term investments and currency translation adjustments			(640)		(640)
us-gaap:NetIncomeLoss				22,592	22,592
Balance at the end of the period at Mar. 31, 2026	$ 21	1,045,877	(665)	(439,546)	605,687
Balance at the end of the period (in shares) at Mar. 31, 2026	76,689,460
Balance at the beginning of the period at Dec. 31, 2025	$ 21	1,029,748	(25)	(462,138)	567,606
Balance at the beginning of the period (in shares) at Dec. 31, 2025	76,294,164
Changes in equity
Unrealized gain (loss) on short-term investments and currency translation adjustments					(1,355)
us-gaap:NetIncomeLoss					48,024
Balance at the end of the period at Jun. 30, 2026	$ 21	1,069,622	(1,380)	(414,114)	654,149
Balance at the end of the period (in shares) at Jun. 30, 2026	77,979,674
Balance at the beginning of the period at Mar. 31, 2026	$ 21	1,045,877	(665)	(439,546)	605,687
Balance at the beginning of the period (in shares) at Mar. 31, 2026	76,689,460
Changes in equity
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan		12,109			12,109
Issuance of Class A ordinary shares under incentive award plans and employee share purchase plan (in shares)	1,290,214
Share-based compensation expense		11,636			11,636
Unrealized gain (loss) on short-term investments and currency translation adjustments			(715)		(715)
us-gaap:NetIncomeLoss				25,432	25,432
Balance at the end of the period at Jun. 30, 2026	$ 21	$ 1,069,622	$ (1,380)	$ (414,114)	$ 654,149
Balance at the end of the period (in shares) at Jun. 30, 2026	77,979,674

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

+ Details

- Definition

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

+ References

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Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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+ Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 14: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 4.E)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480418/310-10-S99-2

+ Details

Product Revenue, Net - Revenue Related Reserves in Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Revenue-related reserves
Revenue-related reserves	$ 17,541	$ 19,566
Location, Statement of Financial Position, Balance [Axis]: us-gaap:AccountsReceivableNetCurrent
Revenue-related reserves
Revenue-related reserves	(1,160)	(831)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesCurrent
Revenue-related reserves
Revenue-related reserves	$ 18,701	$ 20,397

Segment Information and Geographic Data - Operating Segment Selected Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenue:
Revenue	$ 243,600		$ 156,797		$ 457,866	$ 294,582
Costs and operating expenses:
Cost of goods sold	23,572		18,603		44,368	36,471
Collaboration expenses	88,069		52,418		163,646	96,208
Direct research and development expenses by program:
Research and development	40,899		18,753		68,374	38,078
Selling, general and administrative	63,866		46,863		125,017	90,393
Total operating expenses	216,406		136,637		401,405	261,150
Other income, net	3,951		2,717		7,365	5,010
Income before income taxes	31,145		22,877		63,826	38,442
Provision for income taxes	(5,713)		(5,045)		(15,802)	(12,071)
Net income	25,432	$ 22,592	17,832	$ 8,539	48,024	26,371
Other significant non-cash items:
Share-based compensation expense	11,636		8,876		21,692	16,624
Non-cash lease expense	1,011		924		2,005	1,759
Deferred income taxes	2,661		2,644		7,184	5,637
ARCALYST
Direct research and development expenses by program:
Research and development	332		171		673	526
KPL-387
Direct research and development expenses by program:
Research and development	21,442		8,485		37,594	13,663
KPL-1161
Direct research and development expenses by program:
Research and development	766		370		1,721	470
Abiprubart
Direct research and development expenses by program:
Research and development	176		635		229	5,002
Unallocated research and development expenses
Direct research and development expenses by program:
Research and development	18,183		9,092		28,157	18,417
Product revenue, net
Revenue:
Revenue	243,600		156,797		$ 457,866	$ 294,582
Pharmaceutical
Revenue:
Revenue	$ 243,600		$ 156,797

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Tax Disclosure [Line Items]
Provision for income taxes	$ 5,713	$ 5,045	$ 15,802	$ 12,071
Non-cash deferred tax benefit	2,661	$ 2,644	7,184	$ 5,637
Outside Kiniksa US, UK, and Switzerland
Income Tax Disclosure [Line Items]
Material deferred tax assets	$ 0		$ 0

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
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-Topic 740
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Reference 10: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
-Section S99
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 250
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Topic 235
-Publisher FASB
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+ Details

Net Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Numerator:
Net income attributable to ordinary shareholders	$ 25,432	$ 22,592	$ 17,832	$ 8,539	$ 48,024	$ 26,371
Denominator:
Weighted average ordinary shares outstanding - basic	77,577,675		73,438,530		77,050,036	73,041,920
Effect of dilutive securities
Weighted average ordinary shares outstanding - diluted	83,398,051		77,942,082		82,902,904	76,984,393
Basic net income per share	$ 0.33		$ 0.24		$ 0.62	$ 0.36
Diluted net income per share	$ 0.3		$ 0.23		$ 0.58	$ 0.34
Employee Stock Option Member
Effect of dilutive securities
Effect of dilutive securities	4,576,481		3,504,516		4,585,743	3,105,795
Unvested RSUs
Effect of dilutive securities
Effect of dilutive securities	1,044,790		924,675		1,087,832	780,562
Unvested PSUs
Effect of dilutive securities
Effect of dilutive securities	199,105		74,362		179,293	56,116

Product Revenue, Net (Tables)

6 Months Ended

Jun. 30, 2026

Product Revenue, Net

Schedule of product revenue, net


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Product revenue, net	$	243,600	$	156,797	$	457,866	$	294,582

Schedule of balances and activity of the product revenue allowance and reserve categories


	Contractual		Government
	Adjustments		Rebates		Returns		Total
Balance at December 31, 2025	$	4,559	$	11,883	$	3,124	$	19,566
Current provisions relating to sales in the current year		19,469		17,395		1,012		37,876
Adjustments relating to prior years		(8)		(1,463)		(793)		(2,264)
Payments/returns relating to sales in the current year		(18,228)		(7,205)		—		(25,433)
Payments/returns relating to sales in the prior years		(4,551)		(7,522)		(131)		(12,204)
Balance at June 30, 2026	$	1,241	$	13,088	$	3,212	$	17,541


	June 30,		December 31,
	2026		2025
Components of accounts receivable	$	(1,160)	$	(831)
Components of other current liabilities		18,701		20,397
Total revenue-related reserves	$	17,541	$	19,566

Share-Based Compensation - Share Options (Details)	6 Months Ended
Share-Based Compensation - Share Options (Details)	Jun. 30, 2026 $ / shares shares
Options
Number of Shares
Outstanding, beginning of the period \| shares	9,420,208
Granted \| shares	704,571
Exercised \| shares	(1,413,200)
Forfeited \| shares	(221,833)
Outstanding, end of the period \| shares	8,489,746
Share options exercisable \| shares	5,582,824
Share options vested and expected to vest \| shares	8,489,746
Weighted Average Exercise Price
Outstanding, beginning of the period \| $ / shares	$ 18.61
Granted \| $ / shares	47.85
Exercised \| $ / shares	16.35
Forfeited \| $ / shares	26.63
Outstanding, end of the period \| $ / shares	21.2
Share options exercisable \| $ / shares	16.26
Share options vested and expected to vest \| $ / shares	$ 21.2
PSOs
Number of Shares
Outstanding, beginning of the period \| shares	299,706
Granted \| shares	20,387
Forfeited \| shares	(30,920)
Outstanding, end of the period \| shares	289,173
Share options vested and expected to vest \| shares	289,173
Weighted Average Exercise Price
Outstanding, beginning of the period \| $ / shares	$ 28.5
Granted \| $ / shares	44.19
Forfeited \| $ / shares	27.64
Outstanding, end of the period \| $ / shares	29.7
Share options vested and expected to vest \| $ / shares	$ 29.7

Product Revenue, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Product Revenue, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Product Revenue, Net
Revenue	$ 243,600	$ 156,797	$ 457,866	$ 294,582
Contractual Adjustments
Balance at beginning of period			4,559
Current provisions relating to sales in the current year			19,469
Adjustments relating to prior years			(8)
Payments/returns relating to sales in the current year			(18,228)
Payments/returns relating to sales in the prior years			(4,551)
Balance at end of period	1,241		1,241
Government Rebates
Balance at beginning of period			11,883
Current provisions relating to sales in the current year			17,395
Adjustments relating to prior years			(1,463)
Payments/returns relating to sales in current year			(7,205)
Payments/returns relating to sales in the prior years			(7,522)
Balance at end of period	13,088		13,088
Returns
Balance at beginning of period			3,124
Current provisions relating sales in the current year			1,012
Adjustments relating to prior years			(793)
Payments/returns relating to sales in the prior years			(131)
Balance at end of period	3,212		3,212
Total
Balance at beginning of period			19,566
Current provisions relating to sales in the current year			37,876
Adjustments relating to prior years			(2,264)
Payments/returns relating to sales in the current year			(25,433)
Payments/returns relating to sales in the prior years			(12,204)
Balance at end of period	17,541		17,541
Product revenue, net
Product Revenue, Net
Revenue	$ 243,600	$ 156,797	$ 457,866	$ 294,582

Share-Based Compensation (Details) - USD ($) $ in Thousands		6 Months Ended
Share-Based Compensation (Details) - USD ($) $ in Thousands	Jan. 01, 2026	Jun. 30, 2026	Dec. 31, 2025
Options
Share-Based Compensation
Shares outstanding (in shares)		8,489,746	9,420,208
Number of options granted		704,571
RSUs, revenue PSUs, TSR PSUs, and share options
Share-Based Compensation
Total unrecognized compensation cost		$ 122,664
Expenses expected to be recognized over a weighted average remaining period		2 years 4 months 28 days
Development PSUs and PSOs
Share-Based Compensation
Total unrecognized compensation cost		$ 9,506
Unvested PSUs
Share-Based Compensation
Service period		3 years
2018 Plan
Share-Based Compensation
Number of ordinary shares available for future grant		7,845,077
2018 Plan \| Class A ordinary shares \| Maximum
Share-Based Compensation
Additional shares authorized	3,051,742
2015 Plan \| Class A ordinary shares
Share-Based Compensation
Shares outstanding (in shares)		77,296
2018 ESPP \| Class A ordinary shares
Share-Based Compensation
Number of ordinary shares available for future grant		765,514
2018 ESPP \| Class A ordinary shares \| Maximum
Share-Based Compensation
Additional shares authorized	110,000

Segment Information and Geographic Data (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) segment	Jun. 30, 2025 USD ($)
Segment Information and Geographic Data
Number of reportable segments \| segment			1
Pharmaceutical
Segment Information and Geographic Data
Interest income \| $	$ 3,951	$ 2,731	$ 7,365	$ 5,021

- 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

Property and Equipment, Net (Tables)

6 Months Ended

Jun. 30, 2026

Property and Equipment, Net

Schedule of property and equipment, net


	June 30,		December 31,
	2026		2025
Furniture, fixtures and vehicles	$	177	$	177
Computer hardware and software		96		96
Leasehold improvements		4,833		4,639
Lab equipment		4,256		4,006
Construction in progress		752		255
Total property and equipment		10,114		9,173
Less: Accumulated depreciation		(7,539)		(7,230)
Total property and equipment, net	$	2,575	$	1,943

Segment Information and Geographic Data - Property and Equipment by Geographic Region (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Segment Information and Geographic Data
Property and equipment, net	$ 2,575	$ 1,943
Pharmaceutical
Segment Information and Geographic Data
Property and equipment, net	2,575	1,943
Pharmaceutical \| United States
Segment Information and Geographic Data
Property and equipment, net	1,414	1,608
Pharmaceutical \| United Kingdom
Segment Information and Geographic Data
Property and equipment, net	110	76
Pharmaceutical \| Rest of world
Segment Information and Geographic Data
Property and equipment, net	$ 1,051	$ 259

- Definition

Amount, after accumulated depreciation, depletion, and amortization, of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478443/942-360-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-URI https://asc.fasb.org/1943274/2147478451/942-360-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(8))
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-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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-Topic 852
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-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

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-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

- 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

Out-Licensing Agreements (Tables)

6 Months Ended

Jun. 30, 2026

Out-Licensing Agreements

Schedule of contract assets and contract liabilities in connection with license and collaboration agreements


	Balance at				Revenue				Balance at End
	Beginning of Period		Additions		Recognized		Reclassification		of Period
Six Months Ended June 30, 2026
Contract Liabilities:
Huadong ARCALYST	$	31,811	$	—	$	—	$	—	$	31,811

Net Income per Share - Anti-Dilutive Securities (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Anti-dilutive securities excluded from computation of earnings per share
Total anti-dilutive shares	915,524	3,088,869	1,810,104	4,317,037
Employee Stock Option Member
Anti-dilutive securities excluded from computation of earnings per share
Total anti-dilutive shares	883,520	3,026,168	1,485,845	3,804,284
Unvested RSUs
Anti-dilutive securities excluded from computation of earnings per share
Total anti-dilutive shares	32,004	62,701	324,259	512,753

Share Based Compensation - Restricted Share Units (Details)	6 Months Ended
	Jun. 30, 2026
Time-based RSUs
Share-Based Compensation
Vesting percentage	25.00%

- Definition

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

+ References

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+ Details

Fair Value of Financial Assets and Liabilities

6 Months Ended

Jun. 30, 2026

Fair Value of Financial Assets and Liabilities

Fair Value of Financial Assets and Liabilities

2. Fair Value of Financial Assets and Liabilities

Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

●

Level 1—Quoted prices in active markets for identical assets or liabilities.

●

Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

●

Level 3—Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The following tables present information about the Company’s financial instruments measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values:


	Fair Value Measurements
	as of June 30, 2026 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents — money market funds	$	71,484	$	—	$	—	$	71,484
Cash equivalents — U.S. Treasury Securities		—		1,688		—		1,688
Short-term investments — U.S. Treasury Securities		—		350,251		—		350,251
	$	71,484	$	351,939	$	—	$	423,423


	Fair Value Measurements
	as of December 31, 2025 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents — money market funds	$	77,291	$	—	$	—	$	77,291
Short-term investments — U.S. Treasury Securities		—		248,478		—		248,478
	$	77,291	$	248,478	$	—	$	325,769

During the six months ended June 30, 2026 and the year ended December 31, 2025, there were no transfers between Level 1, Level 2 and Level 3. The money market funds were valued using quoted prices in active markets, which represent a Level 1 measurement in the fair value hierarchy. The Company’s cash equivalents and short-term investments as of June 30, 2026 and December 31, 2025 included U.S. Treasury Securities, which are not traded on a daily basis and, therefore, represent a Level 2 measurement in the fair value hierarchy at each period end.

The contractual maturities of short-term investments were as follows:


	June 30,		December 31,
	2026		2025
Maturities within one year	$	184,351	$	179,577
Maturities after one year through five years		165,900		68,901
Total	$	350,251	$	248,478

The following tables summarize short-term investments:


			Gross		Gross
	Amortized		Unrealized		Unrealized		Credit		Fair
	Cost		Gains		Losses		Losses		Value
June 30, 2026
Cash Equivalents - U.S. Treasury Securities	$	1,688	$	—	$	—	$	—	$	1,688
Short-term investments — U.S. Treasury Securities		351,631		—		(1,380)		—		350,251
	$	353,319	$	—	$	(1,380)	$	—	$	351,939


			Gross		Gross
	Amortized		Unrealized		Unrealized		Credit		Fair
	Cost		Gains		Losses		Losses		Value
December 31, 2025
Short-term investments — U.S. Treasury Securities	$	248,354	$	125	$	(1)	$	—	$	248,478
	$	248,354	$	125	$	(1)	$	—	$	248,478

As of June 30, 2026, the Company considers the unrealized losses in its investment portfolio to be temporary in nature and not due to credit losses. The Company has the ability to hold such investments until recovery of the fair value. The Company utilizes the specific identification method in computing realized gains and losses. The Company had no realized gains and losses on its available-for-sale securities for the six months ended June 30, 2026 or 2025.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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+ Details

License and Acquisition Agreements

6 Months Ended

Jun. 30, 2026

License and Acquisition Agreements

License and Acquisition Agreements

10. License and Acquisition Agreements

Regeneron License Agreement

In September 2017, the Company entered into a license agreement (the “Regeneron Agreement”) with Regeneron Pharmaceuticals, Inc. (“Regeneron”), pursuant to which the Company has been granted an exclusive license under certain intellectual property rights controlled by Regeneron to develop and commercialize ARCALYST worldwide, excluding the Middle East and North Africa, for all indications other than those in oncology and local administration to the eye or ear. Upon receiving positive data in RHAPSODY, the Company’s pivotal Phase 3 clinical trial of ARCALYST, Regeneron transferred the biologics license application (“BLA”) for ARCALYST to the Company. In March 2021, when the FDA granted approval of ARCALYST for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older, the Company assumed the sales and distribution of ARCALYST for Cryopyrin-Associated Periodic Syndromes and Deficiency of Interleukin-1 Receptor Antagonist in the United States.

The Company evenly splits profits on sales of ARCALYST with Regeneron, where profits are determined after deducting from net sales of ARCALYST certain costs related to the manufacturing and commercialization of ARCALYST. Such costs include but are not limited to (i) the Company’s cost of goods sold for product used, sold or otherwise distributed for patient use by the Company; (ii) customary commercialization expenses, including the cost of the Company’s field force, and (iii) the Company’s cost to market, advertise and otherwise promote ARCALYST, with such costs identified in subsection (iii) subject to specified limits.  To the extent permitted in accordance with the Regeneron Agreement, the fully-burdened costs incurred by each of the Company and Regeneron in performing (or having performed) the technology transfer of the manufacturing process for ARCALYST drug substance will also be deducted from net sales of ARCALYST to determine profit. The Company also evenly splits with Regeneron any proceeds received by the Company from any licensees, sublicensees and distributors in consideration for the sale, license or other disposition of rights with respect to ARCALYST, including upfront payments, milestone payments and royalties. For the three months ended June 30, 2026 and 2025, the Company recognized $88,049 and $52,389 respectively, of expenses related to the profit sharing agreement presented within collaboration expenses. For the six months ended June 30, 2026 and 2025, the Company recognized $163,626 and $96,164 respectively, of expenses related to the profit sharing agreement presented within collaboration expenses.

The Company has a supply agreement with Regeneron pursuant to which the Company may order both clinical and commercial product. The supply agreement terminates upon the termination of the Regeneron Agreement or the date of completion of the transfer of technology related to the manufacture of ARCALYST. During the three and six months ended June 30, 2026 and 2025, the Company did not incur any research and development expense related to the purchase of drug materials under the supply agreement. As of June 30, 2026 and December 31, 2025, the Company recorded inventory of $34,759 and $29,071 respectively, related to the purchase of commercial product under the supply agreement. As of June 30, 2026, the Company had non-cancelable purchase commitments under the supply agreement (see Note 13).

The Regeneron Agreement will expire when the Company is no longer developing or commercializing any licensed product under the Regeneron Agreement. Either party may terminate the agreement upon the other party’s insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured for 90 days (or 30 days for payment related breaches). Regeneron has the right to terminate the agreement if the Company suspends its

development or commercialization activities for a consecutive 12 month period or does not grant a sublicense to a third party to perform such activities, or if the Company challenges any of the licensed patent rights. The Company may terminate the agreement at any time with one year’s written notice. The Company may also terminate the agreement with three months’ written notice if the licensed product is determined to have certain safety concerns.

Other Agreements

In addition to the license and acquisition agreement discussed above, the Company has license and acquisition agreements that are not individually significant to its operating results or financial condition at this time. Pursuant to the terms of those agreements, the Company may incur potential future development, regulatory and commercial milestone payments, royalty payments on future product sales and annual maintenance fees.

During the three and six months ended June 30, 2026, the Company recorded expenses of $6,520 in our condensed consolidated statements of income related to other research and discovery related arrangements. During the three and six months ended June 30, 2025, the Company recorded $30 and $44 respectively, of expenses in our condensed consolidated statements of income related to other research and discovery related arrangements.

Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2026

Share-Based Compensation

Schedule of restricted and performance-based share activity


	RSUs			PSUs
		Weighted			Weighted
		Average			Average
	Number of	Grant Date		Number of	Grant Date
	Shares	Fair Value		Shares	Fair Value
Unvested as of December 31, 2025	2,074,095	$	23.09	415,307	$	27.25
Granted	358,019	$	47.60	184,771	$	59.39
Vested	(358,289)	$	17.14	—	$	—
Forfeited	(220,211)	$	25.34	(19,308)	$	27.64
Unvested as of June 30, 2026	1,853,614	$	28.71	580,770	$	37.46

Schedule of share option activity under the Plans


	Options			PSOs
		Weighted			Weighted
	Number of	Average		Number of	Average
	Shares	Exercise Price		Shares	Exercise Price
Outstanding as of December 31, 2025	9,420,208	$	18.61	299,706	$	28.50
Granted	704,571	$	47.85	20,387	$	44.19
Exercised	(1,413,200)	$	16.35	—	$	—
Forfeited	(221,833)	$	26.63	(30,920)	$	27.64
Outstanding as of June 30, 2026	8,489,746	$	21.20	289,173	$	29.70
Share options exercisable as of June 30, 2026	5,582,824	$	16.26	—	$	—
Share options vested and expected to vest as of June 30, 2026	8,489,746	$	21.20	289,173	$	29.70

Schedule of share-based compensation expense was classified in the consolidated statements of operations and comprehensive income (loss)


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Cost of goods sold	$	594	$	566	$	1,112	$	995
Research and development expenses		2,502		1,717		4,131		3,219
Selling, general and administrative expenses		8,540		6,593		16,449		12,410
	$	11,636	$	8,876	$	21,692	$	16,624

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

Fair Value of Financial Assets and Liabilities (Tables)

6 Months Ended

Jun. 30, 2026

Fair Value of Financial Assets and Liabilities

Schedule of financial assets and liabilities measured at fair value on a recurring basis


	Fair Value Measurements
	as of June 30, 2026 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents — money market funds	$	71,484	$	—	$	—	$	71,484
Cash equivalents — U.S. Treasury Securities		—		1,688		—		1,688
Short-term investments — U.S. Treasury Securities		—		350,251		—		350,251
	$	71,484	$	351,939	$	—	$	423,423


	Fair Value Measurements
	as of December 31, 2025 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents — money market funds	$	77,291	$	—	$	—	$	77,291
Short-term investments — U.S. Treasury Securities		—		248,478		—		248,478
	$	77,291	$	248,478	$	—	$	325,769

Schedule of contractual maturities of short-term investments


	June 30,		December 31,
	2026		2025
Maturities within one year	$	184,351	$	179,577
Maturities after one year through five years		165,900		68,901
Total	$	350,251	$	248,478

Schedule of short-term investments


			Gross		Gross
	Amortized		Unrealized		Unrealized		Credit		Fair
	Cost		Gains		Losses		Losses		Value
June 30, 2026
Cash Equivalents - U.S. Treasury Securities	$	1,688	$	—	$	—	$	—	$	1,688
Short-term investments — U.S. Treasury Securities		351,631		—		(1,380)		—		350,251
	$	353,319	$	—	$	(1,380)	$	—	$	351,939


			Gross		Gross
	Amortized		Unrealized		Unrealized		Credit		Fair
	Cost		Gains		Losses		Losses		Value
December 31, 2025
Short-term investments — U.S. Treasury Securities	$	248,354	$	125	$	(1)	$	—	$	248,478
	$	248,354	$	125	$	(1)	$	—	$	248,478

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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

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

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

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

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

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

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

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

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

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

+ Details

License and Acquisition Agreements - Regeneron License Agreement (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
License and Acquisition Agreements
Research and development		$ 40,899	$ 18,753	$ 68,374	$ 38,078
Commercial product inventory		70,930		70,930		$ 54,895
Regulatory milestone
License and Acquisition Agreements
Intangible asset - Regulatory milestone		20,000		20,000		20,000
Regeneron \| License agreement
License and Acquisition Agreements
Profit sharing recognized		88,049	52,389	163,626	96,164
Regeneron \| Clinical supply agreement
License and Acquisition Agreements
Research and development		0	$ 0	0	$ 0
Uncured period which causes termination of the agreement, due to insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured	90 days
Notice period to terminate the agreement under payment-related breaches	30 days
Consecutive suspension of activities period for termination of agreement	12 months
Notice period to terminate the agreement	1 year
Notice period to terminate the agreement if products are having safety concerns	3 months
Commercial product inventory		$ 34,759		$ 34,759		$ 29,071

Segment Information and Geographic Data (Tables)

6 Months Ended

Jun. 30, 2026

Segment Information and Geographic Data

Schedule of selected financial information with respect to the company's single operating segment


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
Revenue:
Product revenue, net	$	243,600		$	156,797	$	457,866		$	294,582
License and collaboration revenue		-			-		-			-
Total revenue		243,600			156,797		457,866			294,582
Operating expenses:
Cost of goods sold		23,572			18,603		44,368			36,471
Collaboration expenses		88,069			52,418		163,646			96,208
Direct research and development expenses by program:
ARCALYST		332			171		673			526
KPL-387		21,442			8,485		37,594			13,663
KPL-1161		766			370		1,721			470
Abiprubart		176			635		229			5,002
Unallocated research and development expenses		18,183			9,092		28,157			18,417
Selling, general and administrative		63,866			46,863		125,017			90,393
Total operating expenses		216,406			136,637		401,405			261,150
Other income, net (1)		3,951			2,717		7,365			5,010
Income before income taxes		31,145			22,877		63,826			38,442
Provision for income taxes		(5,713)			(5,045)		(15,802)			(12,071)
Net income	$	25,432		$	17,832	$	48,024		$	26,371

Other significant noncash items:
Share-based compensation expense	$	11,636		$	8,876	$	21,692		$	16,624
Non-cash lease expense		1,011			924		2,005			1,759
Deferred income taxes		2,661			2,644		7,184			5,637

Schedule of total revenue by geographic region of the customer


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
Revenue:
United States	$	243,116		$	156,506	$	457,184		$	294,102
United Kingdom		484			291		682			480
Total revenue	$	243,600		$	156,797	$	457,866		$	294,582

Schedule of property and equipment, net by geographic region


	June 30,		December 31,
	2026		2025
Property and equipment, net
United States	$	1,414	$	1,608
United Kingdom		110		76
Rest of world		1,051		259
Total property and equipment, net	$	2,575	$	1,943

- Definition

Tabular disclosure of segment reporting. Includes, but is not limited to, reconciliation of reportable segment amount to corresponding consolidated total.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-34

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26A

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 25
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-25

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-15

+ Details

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2026	Jul. 24, 2026
Document information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2026
Securities Act File Number	001-38492
Entity Registrant Name	Kiniksa Pharmaceuticals International, plc
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	105 Piccadilly, Second Floor
Entity Address, City or Town	London
Entity Address, Country	GB
Entity Address, Postal Zip Code	W1J 7NJ
City Area Code	781
Local Phone Number	431-9100
Title of 12(b) Security	Class A Ordinary Shares
Trading Symbol	KNSA
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001730430
Amendment Flag	false
Ordinary Shares
Document information
Entity Common Stock, Shares Outstanding		78,024,013
Class A ordinary shares
Document information
Entity Common Stock, Shares Outstanding		48,289,273
Class B ordinary shares
Document information
Entity Common Stock, Shares Outstanding		895,158
Class A1 ordinary shares
Document information
Entity Common Stock, Shares Outstanding		12,781,964
Class B1 ordinary shares
Document information
Entity Common Stock, Shares Outstanding		16,057,618

Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Accrued Expenses
Accrued employee compensation and benefits	$ 20,288	$ 21,437
Accrued inventory and manufacturing	2,276	8,008
Accrued research and development expenses	13,130	6,629
Accrued legal, commercial and professional fees	10,460	5,348
Other	576	598
Total accrued expenses	$ 46,730	$ 42,020

Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Contractual maturities of short-term investments
Maturities within one year	$ 184,351		$ 179,577
Maturities after one year through five years	165,900		68,901
Contractual maturities investments	350,251		248,478
Short-term investments:
Amortized Cost	353,319		248,354
Gross Unrealized Gains			125
Gross Unrealized Losses	(1,380)		(1)
Fair Value	351,939		248,478
Fair Value, Assets Transfers
Fair value of assets transferred from Level 1 to Level 2	0		0
Fair value of assets transferred from Level 2 to Level 1	0		0
Fair value of asset transfer into Level 3	0		0
Fair value of asset transfer out of Level 3	0		0
Realized gains (losses) on securities	0	$ 0
U.S. Treasury Securities \| Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue
Short-term investments:
Amortized Cost	1,688
Fair Value	1,688
U.S. Treasury Securities \| Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments
Short-term investments:
Amortized Cost	351,631		248,354
Gross Unrealized Gains			125
Gross Unrealized Losses	(1,380)		(1)
Fair Value	350,251		248,478
Fair value \| Recurring basis
Assets:
Assets	423,423		325,769
Fair value \| Recurring basis \| Money market funds
Assets:
Cash equivalents	71,484		77,291
Fair value \| Recurring basis \| U.S. Treasury Securities
Assets:
Cash equivalents	1,688
Short-term investments	350,251		248,478
Fair value \| Recurring basis \| Level 1
Assets:
Assets	71,484		77,291
Fair value \| Recurring basis \| Level 1 \| Money market funds
Assets:
Cash equivalents	71,484		77,291
Fair value \| Recurring basis \| Level 2
Assets:
Assets	351,939		248,478
Fair value \| Recurring basis \| Level 2 \| U.S. Treasury Securities
Assets:
Cash equivalents	1,688
Short-term investments	$ 350,251		$ 248,478

Accrued Expenses

6 Months Ended

Jun. 30, 2026

Accrued Expenses

Accrued Expenses

7. Accrued Expenses

Accrued expenses consisted of the following:


	June 30,		December 31,
	2026		2025
Accrued employee compensation and benefits	$	20,288	$	21,437
Accrued inventory and manufacturing		2,276		8,008
Accrued research and development expenses		13,130		6,629
Accrued legal, commercial and professional fees		10,460		5,348
Other		576		598
	$	46,730	$	42,020

Share-Based Compensation - Classification of Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-Based Compensation
Share-based compensation expense	$ 11,636	$ 8,876	$ 21,692	$ 16,624
Location, Statement of Income, Balance [Axis]: us-gaap:CostOfGoodsAndServicesSold
Share-Based Compensation
Share-based compensation expense	594	566	1,112	995
Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense
Share-Based Compensation
Share-based compensation expense	2,502	1,717	4,131	3,219
Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Share-Based Compensation
Share-based compensation expense	$ 8,540	$ 6,593	$ 16,449	$ 12,410

Intangible Assets

6 Months Ended

Jun. 30, 2026

Intangible Assets

Intangible Assets

6. Intangible Assets

Intangible assets, net of accumulated amortization as of June 30, 2026 and December 31, 2025 are summarized in the following table.


		As of June 30, 2026								As of December 31, 2025
	Estimated				Accumulated								Accumulated
	life	Cost			Amortization			Net		Cost			Amortization			Net
Regulatory milestone	20 years	$	20,000		$	5,250		$	14,750	$	20,000		$	4,750		$	15,250

Amortization expense was $250 during the three months ended June 30, 2026 and 2025 and $500 during the six months ended June 30, 2026 and 2025.

Share-Based Compensation

6 Months Ended

Jun. 30, 2026

Share-Based Compensation

Share-Based Compensation

8. Share-Based Compensation

The Company maintains several equity compensation plans, including the 2018 Incentive Award Plan (the “2018 Plan”) and the 2018 Employee Share Purchase Plan (the “2018 ESPP”). Upon the effectiveness of the 2018 Plan, the Company ceased granting awards under its 2015 Equity Incentive Plan (as amended, the “2015 Plan” and together with the 2018 Plan, the “Plans”).

2015 Plan

As of June 30, 2026, there were 77,296 Class A ordinary shares reserved for issuance pursuant to outstanding awards under the 2015 Plan that were granted prior to the effectiveness of the 2018 Plan.

2018 Plan

The 2018 Plan provides for the grant of incentive share options, nonqualified share options, share appreciation rights, restricted shares, dividend equivalents, restricted share units (“RSUs”), PSUs (as defined below) and other share- or cash- based awards. Pursuant to the 2018 Plan’s evergreen provision, the number of shares available for future issuance under the 2018 Plan, as of January 1, 2026, increased by 3,051,742 Class A ordinary shares. As of June 30, 2026, 7,845,077 shares remained available for future grant under the 2018 Plan.

2018 ESPP

In December 2025, the Company’s board of directors approved an increase, as of January 1, 2026, of 110,000 Class A ordinary shares under the 2018 ESPP. As of June 30, 2026, 765,514 Class A ordinary shares were available for future issuance under the 2018 ESPP.

Restricted Share Units

The Company grants RSUs with service conditions to eligible employees as part of its equity incentive compensation. Such RSUs typically vest 25% on each of the first, second, third and fourth anniversaries of the date of grant, subject to continued employment through such dates.

Market and Performance-Based Share Units

In 2024, the Company began periodically granting performance-based restricted share units to certain employees under the 2018 Plan that are earned based upon (i) the achievement of certain specified ARCALYST revenue targets (“Revenue PSUs”) and (ii) the Company’s total shareholder return (“TSR”) relative to the TSR of each member of a specified peer group (“TSR PSUs”). The TSR PSUs and Revenue PSUs are subject to a three-year service period.

In addition, the Company from time-to-time grants performance-based restricted share units to certain eligible employees pursuant to the 2018 Plan that are earned based upon certain development and regulatory milestones (“Development PSUs” and, together with the Revenue PSUs and TSR PSUs, “PSUs”). The Company’s currently outstanding Development PSUs are subject to earnout percentages based upon the date of applicable milestone achievement.

Performance Share Options

Beginning in the second quarter of 2025, the Company began granting performance share options (“PSOs”) to certain eligible employees pursuant to the 2018 Plan representing the right to purchase shares of the Company’s Class A ordinary shares. Such PSOs vest, if at all, upon the achievement of certain specified development and regulatory milestones and are subject to earnout percentages based upon the date of applicable milestone achievement.

The following table summarizes RSU and PSU activity for the six months ended June 30, 2026:


	RSUs			PSUs
		Weighted			Weighted
		Average			Average
	Number of	Grant Date		Number of	Grant Date
	Shares	Fair Value		Shares	Fair Value
Unvested as of December 31, 2025	2,074,095	$	23.09	415,307	$	27.25
Granted	358,019	$	47.60	184,771	$	59.39
Vested	(358,289)	$	17.14	—	$	—
Forfeited	(220,211)	$	25.34	(19,308)	$	27.64
Unvested as of June 30, 2026	1,853,614	$	28.71	580,770	$	37.46

The following table summarizes share options and PSO activity for the six months ended June 30, 2026:


	Options			PSOs
		Weighted			Weighted
	Number of	Average		Number of	Average
	Shares	Exercise Price		Shares	Exercise Price
Outstanding as of December 31, 2025	9,420,208	$	18.61	299,706	$	28.50
Granted	704,571	$	47.85	20,387	$	44.19
Exercised	(1,413,200)	$	16.35	—	$	—
Forfeited	(221,833)	$	26.63	(30,920)	$	27.64
Outstanding as of June 30, 2026	8,489,746	$	21.20	289,173	$	29.70
Share options exercisable as of June 30, 2026	5,582,824	$	16.26	—	$	—
Share options vested and expected to vest as of June 30, 2026	8,489,746	$	21.20	289,173	$	29.70

As of June 30, 2026, total unrecognized compensation cost related to RSUs, Revenue PSUs, TSR PSUs, and share options was $122,664 which is expected to be recognized over a weighted average remaining period of 2.41 years. As of June 30, 2026, total unrecognized compensation cost related to outstanding Development PSUs and PSOs was $9,506 which will be recognized when the applicable milestones are deemed probable of achievement through the date the awards vest with a cumulative catch-up.

Share-Based Compensation

Share-based compensation expense was classified in the condensed consolidated statements of operations and comprehensive income as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Cost of goods sold	$	594	$	566	$	1,112	$	995
Research and development expenses		2,502		1,717		4,131		3,219
Selling, general and administrative expenses		8,540		6,593		16,449		12,410
	$	11,636	$	8,876	$	21,692	$	16,624

Net Income per Share (Tables)

6 Months Ended

Jun. 30, 2026

Net Income per Share

Schedule of basic and diluted net income attributable to ordinary shareholders


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Numerator:
Net income attributable to ordinary shareholders	$	25,432	$	17,832	$	48,024	$	26,371
Denominator:
Weighted average ordinary shares outstanding—basic		77,577,675		73,438,530		77,050,036		73,041,920
Effect of dilutive securities
Options to purchase ordinary shares		4,576,481		3,504,516		4,585,743		3,105,795
Unvested RSUs		1,044,790		924,675		1,087,832		780,562
Unvested PSUs		199,105		74,362		179,293		56,116
Weighted average ordinary shares outstanding—diluted		83,398,051		77,942,082		82,902,904		76,984,393

Basic net income per share	$	0.33	$	0.24	$	0.62	$	0.36
Diluted net income per share	$	0.30	$	0.23	$	0.58	$	0.34

Schedule of anti-dilutive securities excluded from the computation of diluted EPS per share attributable to ordinary shareholders


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Share options to purchase ordinary shares		883,520		3,026,168		1,485,845		3,804,284
Unvested RSUs		32,004		62,701		324,259		512,753
Total anti-dilutive shares		915,524		3,088,869		1,810,104		4,317,037

Property and Equipment, Net

6 Months Ended

Jun. 30, 2026

Property and Equipment, Net

Property and Equipment, Net

5. Property and Equipment, Net

Property and equipment, net consisted of the following:


	June 30,		December 31,
	2026		2025
Furniture, fixtures and vehicles	$	177	$	177
Computer hardware and software		96		96
Leasehold improvements		4,833		4,639
Lab equipment		4,256		4,006
Construction in progress		752		255
Total property and equipment		10,114		9,173
Less: Accumulated depreciation		(7,539)		(7,230)
Total property and equipment, net	$	2,575	$	1,943

Depreciation expense was $165 and $13 during the three months ended June 30, 2026 and 2025, respectively and $309 and $48 during the six months ended June 30, 2026 and 2025, respectively.

- Definition

The entire disclosure for property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
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+ Details

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2026

Accrued Expenses

Schedule of accrued expenses


	June 30,		December 31,
	2026		2025
Accrued employee compensation and benefits	$	20,288	$	21,437
Accrued inventory and manufacturing		2,276		8,008
Accrued research and development expenses		13,130		6,629
Accrued legal, commercial and professional fees		10,460		5,348
Other		576		598
	$	46,730	$	42,020

Segment Information and Geographic Data

6 Months Ended

Jun. 30, 2026

Segment Information and Geographic Data

Segment Information and Geographic Data

14. Segment Information and Geographic Data

The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is on developing and commercializing novel therapies that target cardiovascular diseases with significant unmet medical need. The Company’s Chief Operating Decision Maker (“CODM”) is the Chief Executive Officer. The Company’s CODM reviews consolidated operating results and decides how to allocate resources based on net income that also is reported on the income statement as consolidated net income. The measure of segment assets is reported on the balance sheet as total consolidated assets. The CODM utilizes net income to make key decisions about how to allocate resources across the Company’s commercial product and development programs.

The following table presents selected financial information with respect to the Company’s single operating segment for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
Revenue:
Product revenue, net	$	243,600		$	156,797	$	457,866		$	294,582
License and collaboration revenue		-			-		-			-
Total revenue		243,600			156,797		457,866			294,582
Operating expenses:
Cost of goods sold		23,572			18,603		44,368			36,471
Collaboration expenses		88,069			52,418		163,646			96,208
Direct research and development expenses by program:
ARCALYST		332			171		673			526
KPL-387		21,442			8,485		37,594			13,663
KPL-1161		766			370		1,721			470
Abiprubart		176			635		229			5,002
Unallocated research and development expenses		18,183			9,092		28,157			18,417
Selling, general and administrative		63,866			46,863		125,017			90,393
Total operating expenses		216,406			136,637		401,405			261,150
Other income, net (1)		3,951			2,717		7,365			5,010
Income before income taxes		31,145			22,877		63,826			38,442
Provision for income taxes		(5,713)			(5,045)		(15,802)			(12,071)
Net income	$	25,432		$	17,832	$	48,024		$	26,371

Other significant noncash items:
Share-based compensation expense	$	11,636		$	8,876	$	21,692		$	16,624
Non-cash lease expense		1,011			924		2,005			1,759
Deferred income taxes		2,661			2,644		7,184			5,637

(1)Includes interest income of $3,951 and $7,365 for the three and six months ended June 30, 2026, respectively. Includes interest income of $2,731 and $5,021 for the three and six months ended June 30, 2025, respectively.

The following table presents total revenue by geographic region of the customer for the three and six months ended June 30, 2026 and 2025:


	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2026			2025		2026			2025
Revenue:
United States	$	243,116		$	156,506	$	457,184		$	294,102
United Kingdom		484			291		682			480
Total revenue	$	243,600		$	156,797	$	457,866		$	294,582

The following table presents property and equipment, net by geographic region (in thousands):


	June 30,		December 31,
	2026		2025
Property and equipment, net
United States	$	1,414	$	1,608
United Kingdom		110		76
Rest of world		1,051		259
Total property and equipment, net	$	2,575	$	1,943

- Definition

The entire disclosure for segment reporting.

+ References

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+ Details