What changed in this filing

/stocks — the workspaceLOADING

Item 9A. Controls and Procedures

2026-02-24 compared with 2025-02-25 · 353 added, 342 removed, 1107 unchanged (39% of the section changed)

13 unchanged sentences

Trading Arrangements.

The following table shows the “Rule 10b5-1 trading arrangements” or “non-Rule 10b5-1 trading arrangements” (as each term is defined in Item 408(a) of Regulation S-K) adopted, amended or terminated by our directors and officers during the three months ended December 31, 2024:

During the three months ended December 31, 2025, certain of our directors and officers entered into, modified or terminated contracts, instructions or written plans for the purchase or sale of our ordinary shares that are intended to satisfy the affirmative defense conditions specified in Rule 10b5-1(c) under the Exchange Act, as described below:

Trading Arrangement

3 unchanged sentences

Maximum Shares Subject to Trading Plan

SVP, Chief Commercial Officer

Chairman and CEO

October 31, 2025

December 31, 2026

EVP, Chief Medical Officer

November 18, 2025

April 17, 2026

November 19, 2026

(1) A trading arrangement may expire on an earlier date if all contemplated transactions are completed before such trading arrangement’s expiration date, upon termination by broker or the holder of the trading arrangement or as otherwise provided in the trading arrangement.

43 unchanged sentences

and Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd., dated as of February 21, 2022

Collaboration and License Agreement (Mavrilimumab), by and between Kiniksa Pharmaceuticals (UK), Ltd.

and Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd., dated as of February 21, 2022

Incorporated by Reference

Exhibit Description

License Agreement, dated August 2, 2022, by and among Kiniksa Pharmaceuticals (UK), Ltd., Genentech, Inc.

20 unchanged sentences

Amended and Restated Employment Agreement, dated as of May 29, 2018, by and between Kiniksa Pharmaceuticals Corp.

Incorporated by Reference

Exhibit Description

Employment Agreement, effective as of January 1, 2025, by and between Kiniksa Pharmaceuticals Corp.

1 unchanged sentence

Employment Agreement, effective as of January 1, 2025, by and between Eben Tessari and Kiniksa Pharmaceuticals Corp.

Change in Control Agreement, effective as of January 1, 2025, by and between Michael Megna and Kiniksa Pharmaceuticals Corp.

Employment Agreement, effective as of July 1, 2025, by and between Michael Megna and Kiniksa Pharmaceuticals Corp.

Employment Agreement, effective as of January 1, 2025, by and between Kiniksa Pharmaceuticals Corp.

11 unchanged sentences

Form of 2024 Performance Share Unit Grant Notice and 2024 Performance Share Unit Award Agreement

Form of 2025 Performance Share Unit Grant Notice and 2025 Performance Share Unit Award Agreement

2018 Employee Share Purchase Plan

Offering Document under the 2018 Employee Share Purchase Plan

KPL-387 Long-Term Incentive Plan for Executive Officers

Incorporated by Reference

Exhibit Description

Form of Milestone 1 Cash Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Form of Milestone 2 Cash Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Form of Milestone 1 PSU Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Form of Milestone 2 PSU Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Form of Milestone 1 Option Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Form of Milestone 2 Option Award Grant Notice and Agreement under the KPL-387 Long-Term Incentive Plan

Agreement for the Provision of Depositary Services and Custody Services, dated as of June 28, 2024, in respect of Kiniksa Pharmaceuticals International, plc A Depositary Receipts and A1 Depositary Receipts among Computershare Trust Company, N.A., Kiniksa Pharmaceuticals International, plc and Holders of A Depositary Receipts and A1 Depositary Receipts

9 unchanged sentences

Section 1350 Certification of Chief Financial Officer

Incorporated by Reference

Exhibit Description

Policy for Recovery of Erroneously Awarded Compensation

19 unchanged sentences

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Chief Executive Officer and Chairman of the Board of Directors (principal executive officer)

Chief Executive Officer and Chairman of the Board of Directors

(principal executive officer)

February 24, 2026

/s/ Mark Ragosa

Chief Financial Officer (principal financial officer)

Chief Financial Officer

(principal financial officer)

February 24, 2026

/s/ Michael R.

Group VP, Finance and Chief Accounting Officer (principal accounting officer)

Chief Accounting Officer

(principal accounting officer)

February 24, 2026

49 unchanged sentences

Critical Audit Matters

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments.

The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

The critical audit matters communicated below are matters arising from the current period audit of the consolidated financial statements that were communicated or required to be communicated to the audit committee and that (i) relate to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments.

The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Product Revenue, Net

As described in Notes 2 and 4 to the consolidated financial statements, the Company’s product is sold through a third party logistics provider that distributes primarily through a network of authorized specialty pharmacies and specialty distributors.

The Company’s net revenue from such product sales is recognized at the transaction price when the specialty pharmacy or specialty distributors obtain control of the Company’s products, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider.

The Company’s net revenues represent total revenues adjusted for discounts and allowances, including estimated cash discounts, chargebacks, rebates, returns, copay assistance, and specialty pharmacy and distributor fees.

For the year ended December 31, 2025, the Company recognized $677.6 million of product revenue, net.

The principal consideration for our determination that performing procedures relating to product revenue, net, is a critical audit matter is a high degree of auditor effort in performing procedures related to the Company’s recognition of product revenue, net.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements.

These procedures included testing the effectiveness of controls relating to the recognition of product revenue, net.

These procedures also included, among others (i) testing revenue recognized for a sample of revenue transactions by obtaining and inspecting source documents, such as invoices, customer purchase orders, shipping documents, and cash receipts;

and (ii) testing a sample of discounts and allowances transactions related to chargebacks and rebates by obtaining and inspecting source documents, which included support for contractual arrangements, units sold, and rebate payments.

Accrued Research and Development Costs

1 unchanged sentence

When billing terms under these contracts do not coincide with the timing of when the work is performed, management is required to make estimates of outstanding obligations to those third parties as of the end of the reporting period.

Within accrued expenses, total accrued research and development expenses amounted to $11.0 million as of December 31, 2024, which include accruals for these estimated research and development obligations.

Total accrued research and development expenses related to these estimated research and development obligations were $6.6 million as of December 31, 2025.

Accrual estimates are based on a number of factors, including management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts, communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts.

Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period.

The principal considerations for our determination that performing procedures relating to accrued research and development costs is a critical audit matter are (i) the significant judgment by management in estimating the accrued research and development costs and (ii) a high degree of auditor judgment, subjectivity, and effort in performing procedures and evaluating audit evidence for these accrued costs and the factors related to management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts and communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced.

The principal considerations for our determination that performing procedures relating to accrued research and development costs is a critical audit matter are (i) the significant judgment by management when developing the estimate of the accrued research and development costs and (ii) a high degree of auditor judgment, subjectivity, and effort in performing procedures and evaluating audit evidence for the factors related to management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts, and communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements.

These procedures included testing the effectiveness of controls relating to accrued research and development costs, including controls over the review of contracts, accumulating information on actual costs incurred during the period, and assessment of progress towards completion of the research and development activities.

These procedures also included, among others (i) testing management’s process for estimating accrued research and development costs;

(ii) evaluating the appropriateness of the methodology used by management to determine the estimate;

(iii) evaluating the reasonableness of the factors related to management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts and communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced by testing, on a sample basis, specific tasks and the associated cost incurred for services the Company has not yet been invoiced for or otherwise notified of the actual cost at period end, and (iv) testing the completeness and accuracy of the data inputs to the estimate, including total costs included within executed contracts and actual billed expenses under these contracts.

These procedures also included, among others (i) testing management’s process for developing the estimate of accrued research and development costs;

(ii) evaluating the appropriateness of the methodology used by management to develop the estimate;

(iii) evaluating the reasonableness of the factors related to management’s assessment of progress towards completion of the research and development activities, invoicing to date under the contracts, and communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced by testing, on a sample basis, specific tasks and the associated cost incurred for services the Company has not yet been invoiced for or otherwise notified of the actual cost at December 31, 2025, and (iv) testing the completeness and accuracy of underlying data used by management.

/s/ PricewaterhouseCoopers LLP

21 unchanged sentences

Accrued expenses

Deferred revenue

Operating lease liabilities

13 unchanged sentences

Class A1 ordinary shares, $ 0.000273235 par value;

12,781,964 shares and 16,826,468 issued and outstanding as of December 31, 2024 and 2023, respectively

12,781,964 shares issued and outstanding as of December 31, 2025 and 2024

Class B1 ordinary shares, $ 0.000273235 par value;

1 unchanged sentence

Additional paid-in capital

Accumulated other comprehensive income (loss)

Accumulated other comprehensive loss

Accumulated deficit

15 unchanged sentences

Income (loss) from operations

Other income, net

Income (loss) before income taxes

23 unchanged sentences

Share-based compensation expense

Unrealized gain on short-term investments and currency translation adjustments

Unrealized loss on short-term investments and currency translation adjustments

Balances at December 31, 2023

5 unchanged sentences

Share-based compensation expense

Unrealized loss on short-term investments and currency translation adjustments

Unrealized gain on short-term investments and currency translation adjustments

Balances at December 31, 2025

9 unchanged sentences

Non-cash lease expense

Amortization (accretion) of discounts on short-term investments

Gain on disposal of property and equipment

Loss on disposal of property and equipment

Net amortization (accretion) of discounts on short-term investments

Net (gain) loss on disposal of property and equipment

Deferred income taxes

41 unchanged sentences

In addition, references to “ordinary shares” prior to the Redomiciliation are to Kiniksa Bermuda’s common shares and from and after the Redomiciliation are to Kiniksa International’s ordinary shares.

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 US and foreign regulations and approval requirements.

The Company subsequently liquidated Kiniksa Bermuda in November 2025, completing the Redomiciliation.

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.

Principles of Consolidation

2 unchanged sentences

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries, Kiniksa Pharmaceuticals Corp.

(“Kiniksa US”), Kiniksa Bermuda and Kiniksa Pharmaceuticals (UK), Ltd.

(“Kiniksa US”) and Kiniksa Pharmaceuticals (UK), Ltd.

(“Kiniksa UK”) as well as the subsidiary of Kiniksa US, Primatope Therapeutics, Inc.

(“Primatope”) and subsidiaries of Kiniksa UK, Kiniksa Pharmaceuticals (Germany) GmbH (“Kiniksa Germany”), Kiniksa Pharmaceuticals (France) SARL (“Kiniksa France”), and Kiniksa Pharmaceuticals, GmbH (“Kiniksa Switzerland”), after elimination of all significant intercompany accounts and transactions.

(“Primatope”) and subsidiaries of Kiniksa UK, Kiniksa Pharmaceuticals, GmbH (“Kiniksa Switzerland”), Kiniksa Pharmaceuticals (Germany) GmbH (“Kiniksa Germany”) and Kiniksa Pharmaceuticals (France) SARL (“Kiniksa France”), after elimination of all significant intercompany accounts and transactions.

Where the Kiniksa Pharmaceuticals International, plc entity is referred to in its single, unconsolidated form, it is referred to as “Kiniksa International”.

2 unchanged sentences

These reclassifications had no effect on the reported results of operations and comprehensive loss or cash flows.

A reclassification has been made to the Consolidated Balance Sheet for fiscal year ended December 31, 2023, to reclassify the collaboration accrued expenses to be a separate line item.

A reclassification has been made to Note 9 Accrued Expenses for fiscal year ended December 31, 2024, to reclassify the accrued inventory and manufacturing to be a separate line item.

KINIKSA PHARMACEUTICALS, LTD.

3 unchanged sentences

The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting period.

Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the recognition of revenue, the accrual for research and development expenses, and the valuation of the Company’s deferred tax assets.

Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the recognition of revenue, the accrual for research and development expenses, uncertain tax positions, and the valuation of the Company’s deferred tax assets.

Estimates are periodically reviewed in light of changes in circumstances, facts and experience.

2 unchanged sentences

Reporting and Functional Currency

The financial results of the Company’s global activities are reported in U.S.

dollars (“USD”) and its foreign subsidiaries other than Kiniksa UK and Kiniksa Switzerland generally utilize their respective local currency to be their functional currency.

The financial results of the Company’s global activities are reported in United States dollars (“USD”) and its foreign subsidiaries other than Kiniksa UK and Kiniksa Switzerland generally utilize their respective local currency to be their functional currency.

Transactions in other currencies are recorded in the functional currency at the rate of exchange prevailing when the transactions occur.

4 unchanged sentences

As of December 31, 2025, the Company had an accumulated deficit of $ 462,138 .

During the year ended December 31, 2024, the Company recorded a net loss of $ 43,193 and provided $ 25,689 of cash from operating activities.

During the year ended December 31, 2025, the Company recorded a net income of $ 59,005 and provided $ 137,985 of cash from operating activities.

As of December 31, 2025, the Company had cash, cash equivalents and short-term investments of $ 414,074 .

Based on its current operating plan, the Company expects that its cash, cash equivalents and short-term investments will be sufficient to fund its operations and capital expenditure requirements for at least twelve months from the issuance date of these consolidated financial statements.

The future viability of the Company beyond that point is dependent on its ability to fund its operations through sales of ARCALYST and/or raise additional capital, as needed.

If the Company is unable to grow or sustain ARCALYST commercial revenue in future periods, the Company would need to seek additional financing through public or private securities offerings, debt financings, or other sources, which may include licensing, collaborations or other strategic transactions or arrangements.

Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all.

If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its commercialization efforts, research and development programs for product candidates or product portfolio expansion, which could adversely affect its business prospects, or the Company may be unable to continue operations.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Based on its current operating plan, the Company expects that its cash, cash equivalents and short-term investments combined with cash anticipated to be generated from sales of ARCALYST will be sufficient to fund its operations and capital expenditure requirements for at least twelve months from the issuance date of these consolidated financial statements.

Summary of Significant Accounting Policies

1 unchanged sentence

The Company classifies deposits in banks, money market funds and cash invested temporarily in various instruments with maturities of three months or less at the time of purchase as cash and cash equivalents.

As of December 31, 2024 and 2023 cash and cash equivalents consisted principally of U.S.

Treasury notes, amounts held in money market accounts and cash on deposit at commercial banks.

As of December

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

31, 2025 and 2024 cash and cash equivalents consisted principally of amounts held in money market accounts and cash on deposit at commercial banks.

Short-Term Investments

The Company generally invests its excess cash in money market funds and short-term investments in U.S.

Treasury notes.

Such investments which are included in short-term investments on the Company’s consolidated balance sheets are considered available-for-sale (“AFS”) debt securities and are reported at fair value with unrealized gains and losses recognized in accumulated other comprehensive income (loss) in stockholders’ equity, net of related tax effects.

Treasury securities.

The Company has classified its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations.

Realized gains and losses, if any, on short-term investments are included in interest income.

If the AFS debt security’s fair value declines below its amortized cost the Company considers all available evidence to evaluate the extent to which the decline is due to credit-related factors or noncredit-related factors.

If the decline is due to noncredit-related factors then no credit loss is recorded and the unrealized loss is recognized in accumulated other comprehensive income (loss) in stockholders’ equity, net of the related tax effects.

If the decline is due to noncredit-related factors then no credit loss is recorded and the unrealized loss is recognized in accumulated other comprehensive income (loss) in shareholders’ equity, net of the related tax effects.

If the decline is considered to be a credit-related impairment, it is recognized as an allowance on the consolidated balance sheet with a corresponding charge to the consolidated statement of operations and comprehensive income (loss).

14 unchanged sentences

Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs.

Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the

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.

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

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.

1 unchanged sentence

The Company’s cash equivalents and short-term investments, consisting of money market accounts and U.S.

Treasury notes, are carried at fair value, determined based on Level 1 and 2 inputs in the fair value hierarchy described above (see Note 3).

Treasury securities, are carried at fair value, determined based on Level 1 and 2 inputs in the fair value hierarchy described above (see Note 3).

The carrying values of the Company’s prepaid expenses and other current assets, accounts receivable, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities.

7 unchanged sentences

Leases with a term greater than one year are recognized on the balance sheet as ROU assets with corresponding lease liabilities and, if applicable, long-term lease liabilities.

The Company has elected not to recognize leases with a term of one year or less on its balance sheet, the Company recognizes lease expense for these leases on a straight-line basis over the lease term.

The Company has elected not to recognize leases with a term of one year or less on its balance sheet.

The Company recognizes lease expense for these leases on a straight-line basis over the lease term.

Operating leases, ROU assets and their corresponding lease liabilities are recorded based on the present value of lease payments over the expected remaining lease term.

6 unchanged sentences

The Company has elected to account for the lease and non-lease components of each of its operating leases as a single lease component and allocate all of the arrangement consideration to the lease component only.

The lease component results in an operating ROU asset being recorded on the balance sheet and amortized on a straight-line basis as lease expense.

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

component results in an operating ROU asset being recorded on the balance sheet and amortized on a straight-line basis as lease expense.

Property and Equipment

14 unchanged sentences

The Company performs an assessment of the recoverability of capitalized inventories during each reporting period and writes down any excess and obsolete inventory to its net realizable value in the period in which the impairment is first identified.

Such impairment charges, should they occur, are recorded as a component of cost of sales in the Company’s consolidated statements of operations and comprehensive loss.

Such impairment charges, should they occur, are recorded as a component of cost of sales in the Company’s consolidated statements of operations and comprehensive income (loss).

The determination of whether inventory costs will be realizable requires the use of estimates by management.

If actual market conditions are less favorable than projected by management, additional writedown of inventory may be required.

If actual market conditions are less favorable than projected by management, additional write-down of inventory may be required.

Finished goods that can be used in either the production of clinical or commercial products is expensed as research and development costs when identified and labeled for use in clinical trials as the products are required to be re-labeled for alternative uses.

The finished goods inventory that will ultimately be distributed free of charge under the Company’s patient assistance program are recognized as selling expense when they are labeled as free goods.

The finished goods inventory that will ultimately be distributed free of charge under the Company’s patient assistance program are recognized as selling expenses when they are labeled as free goods.

The Company is conducting a technology transfer of ARCALYST drug substance manufacturing from Regeneron Pharmaceuticals, Inc.

2 unchanged sentences

During the years ended December 31, 2025, 2024 and 2023 the Company incurred $ 11,704 , $ 15,849 and $ 3,265 , respectively, of expense related to the technology transfer of ARCALYST drug substance manufacturing in cost of goods sold.

No expenses were incurred in the year ending December 31, 2022.

KINIKSA PHARMACEUTICALS, LTD.

12 unchanged sentences

Product Revenue, Net

Following the FDA approval of ARCALYST in March 2021, the Company began generating product revenue from sales of ARCALYST in April 2021.

Following the FDA approval of ARCALYST in March 2021, the Company began generating product revenue from sales of ARCALYST.

ARCALYST is sold through a third party logistics provider that distributes primarily through a network of authorized specialty pharmacies and specialty distributors (“customer”), which deliver the medication to patients by mail.

33 unchanged sentences

Government and other chargebacks are recognized as reduction of revenue upon the sale to the Customers.

These items are payable to customers and other rebates that are payable to other third party payors and healthcare professionals are classified as accrued expense liabilities.

These items are payable to customers and other rebates that are payable to other third party payors are classified as accrued expense liabilities.

Cash Discounts

5 unchanged sentences

The Company pays a variable fee to the specialty pharmacies to provide the data.

The Company also pay the specialty pharmacies a fee in exchange for providing distribution and inventory management services, including the provision of inventory management data to the Company.

The Company also pays the specialty pharmacies a fee in exchange for providing distribution and inventory management services, including the provision of inventory management data to the Company.

The Company estimates the fee for service accruals and allowances based on sales to each specialty pharmacy and the applicable contracted rate.

11 unchanged sentences

Other Incentives

Other incentives include a co-pay assistance program for eligible patients with commercial insurance in the U.S.

Other incentives include a co-pay assistance program for eligible patients with commercial insurance in the United States.

The co-pay assistance programs assist certain commercially insured patients by reducing each participating patient’s financial responsibility for the purchase price, up to a specified dollar amount of assistance.

1 unchanged sentence

Collaboration expenses consist of Regeneron’s share of the profit related to ARCALYST sales under the license agreement (the “Regeneron Agreement”) with Regeneron (see Note 13) and the cost of products sold under collaboration agreements.

The Company also evenly split 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.

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.

License and Collaboration Revenue

3 unchanged sentences

For collaboration arrangements within the scope of Topic 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of Topic 808 and which elements of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of Topic 606.

For elements of collaboration arrangements that are accounted for pursuant to ASC 606, the Company identifies the performance obligations and allocate the total consideration the Company expects to receive on a relative standalone selling price basis to each performance obligation.

For elements of collaboration arrangements that are accounted for pursuant to ASC 606, the Company identifies the performance obligations and allocates the total consideration the Company expects to receive on a relative standalone selling price basis to each performance obligation.

Variable consideration such as performance-based milestones will be included in the total consideration if the Company expects to receive such consideration and if it is probable that the inclusion of the variable consideration will not result in a significant reversal in the cumulative amount of revenue recognized under the arrangement.

11 unchanged sentences

Upon FDA approval and commercial launch of ARCALYST in March 2021, the Company capitalized the $ 20,000 milestone payment to Regeneron for a specified regulatory milestone as a f inite-lived intangible asset (see Note 13).

The intangible asset will be amortized on a straight-line basis over the life of the underlying intellectual property of 20 years .

Amortization expense will be recorded as cost of goods sold in the Company’s consolidated statement of operations and comprehensive income (loss).

The intangible asset is amortized on a straight-line basis over the life of the underlying intellectual property of 20 years .

Amortization expense is recorded as cost of goods sold in the Company’s consolidated statement of operations and comprehensive income (loss).

Impairment of Long-Lived Assets

The Company assesses the impairment of long-lived assets, including intangible assets and property and equipment, whenever events or changes in business circumstances indicate that the carrying amounts of the assets may not be fully recoverable.

When such events occur, the Company determines whether there has been an impairment in value by comparing the asset’s carrying value with its fair value, as measured by the anticipated undiscounted net cash flows of the asset.

When such events occur, the Company determines whether there has been an impairment in value by comparing the asset’s carrying value with the anticipated undiscounted net cash flows of the asset.

If an impairment in value exists, the asset is written down to its estimated fair value.

The Company has not recognized any impairment losses through December 31, 2024 and there have been no events that triggered an impairment analysis.

The Company has no t recognized any impairment losses through December 31, 2025 and there have been no events that triggered an impairment analysis.

Research and Development Costs

2 unchanged sentences

Non-refundable prepayments determined to be used within one year for goods or services that will be used or rendered for future research and development activities are recorded as prepaid expenses.

Non-refundable prepayments or minimum balance requirements associated to clinical trials determined to not be used within one year are classified as other long-term assets.

Non-refundable prepayments or minimum balance requirements associated with clinical trials determined to not be used within one year are classified as other long-term assets.

Such amounts are recognized as an expense as the goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered, or the services rendered.

4 unchanged sentences

The Company records accruals for estimated ongoing research and development costs.

When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of

When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of outstanding obligations to those third parties as of the end of the reporting period.

Any accrual estimates are based on a

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

outstanding obligations to those third parties as of the end of the reporting period.

Any accrual estimates are based on a number of factors, including the Company’s knowledge of the progress towards completion of the research and development activities, invoicing to date under the contracts, communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts.

number of factors, including the Company’s assessment of the progress towards completion of the research and development activities, invoicing to date under the contracts, communication from the research institution or other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts.

Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period.

18 unchanged sentences

Prior to May 2018, the Company was a private company and, accordingly, lacked company-specific historical and implied volatility information for its shares.

Therefore, it estimated its expected share price volatility based on the historical volatility of the Company and historical volatility of publicly traded peer companies until such time as it had adequate historical data regarding the

The expected term of the Company’s options has been determined utilizing the

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

volatility of its own traded share price.

The expected term of the Company’s options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options.

“simplified” method for awards that qualify as “plain-vanilla” options.

The expected term of options granted to non-employees is equal to the contractual term of the option award.

The risk-free interest rate is determined by reference to the U.S.

Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award.

The risk-free interest rate is determined by reference to the United States Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award.

Expected dividend yield is based on the fact that the Company has never paid cash dividends on ordinary shares and does not expect to pay any cash dividends in the foreseeable future.

8 unchanged sentences

Diluted net income (loss) per share attributable to ordinary shareholders is computed based on the treasury method by dividing the diluted net income (loss) attributable to ordinary shareholders by the weighted average number of ordinary shares outstanding for the period, including potential dilutive ordinary shares.

For purpose of this calculation, outstanding share options and unvested restricted share units are considered potential dilutive ordinary shares.

For purpose of this calculation, outstanding share options, unvested restricted share units and unvested performance-based share units for which the market or performance condition has been met as of the date of determination, are considered potential dilutive ordinary shares.

In periods in which the Company reports a net loss attributable to ordinary shareholders, diluted net loss per share attributable to ordinary shareholders is the same as basic net loss per share attributable to ordinary shareholders, since dilutive ordinary shares are not assumed to have been issued if their effect is anti-dilutive.

10 unchanged sentences

Following the Redomiciliation, the Company is incorporated and principally subject to taxation in the United Kingdom.

Under the current laws of Bermuda, tax on a company’s income is assessed at a zero percent tax rate.

Under the previous laws of Bermuda, tax on a company’s income is assessed at a zero percent tax rate.

As a result, the Company has not recorded any income tax benefits from its losses incurred in Bermuda during the reporting periods in which it was incorporated there, and no net operating loss carryforwards will be available to the Company for those losses.

Following the Redomiciliation, the Company’s income is subject to the enacted United Kingdom statutory corporate tax rate and net operating losses incurred have an indefinite carryforward.

The Company’s wholly owned U.S.

subsidiaries, Kiniksa US and Primatope, are subject to federal and state income taxes in the United States.

The Company’s wholly owned subsidiary Kiniksa Bermuda remains subject to taxation, if any, in Bermuda.

The Company’s wholly owned subsidiary Kiniksa UK, and Kiniksa UK’s wholly owned subsidiaries, Kiniksa Germany, Kiniksa France, and Kiniksa Switzerland are subject to taxation in their respective countries.

Certain of the Company’s subsidiaries operate under cost plus arrangements.

The Company’s wholly owned United States subsidiaries, Kiniksa US and Primatope, are subject to federal and state income taxes in the United States.

The Company’s wholly owned subsidiary Kiniksa Bermuda remains subject to taxation, if any, in Bermuda for the period of time prior to its liquidation in November 2025.

The Company’s wholly owned subsidiary Kiniksa UK, and Kiniksa UK’s wholly owned subsidiaries, Kiniksa Switzerland, Kiniksa Germany, and Kiniksa France are subject to taxation in their respective countries.

Certain of the Company’s subsidiaries operate under cost plus intercompany arrangements.

The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized.

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Recently Issued Accounting Pronouncements

In December 2023, the FASB issued Accounting Standards Update (“ASU”) No.

2023-09, Income Taxes (Topic 740):

Improvements to Income Tax Disclosures .

The amendments require (i) enhanced disclosures in connection with an entity's effective tax rate reconciliation and (ii) income taxes paid disaggregated by jurisdiction.

The amendments are effective for annual periods beginning after December 15, 2024.

The Company does not expect the adoption of the amendments to have a material impact on its financial statements.

In November 2024, the FASB issued ASU 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40):

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.

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 November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280):

Improvements to Reportable Segment Disclosures , requiring public entities to disclose information about their reportable segments’ significant expenses and other segment items on an interim and annual basis.

Public entities with a single reportable segment are required to apply the disclosure requirements in ASU 2023-07, as well as all existing segment disclosures and reconciliation requirements in ASC 280 on an interim and annual basis.

The Company adopted ASU 2023-07 during the year ended December 31, 2024.

See Note 17 Segment Information in the accompanying notes to the consolidated financial statements for further detail.

In December 2023, the FASB issued ASU No.

2023-09, Income Taxes (Topic 740):

Improvements to Income Tax Disclosures .

The amendments require (i) enhanced disclosures in connection with an entity's effective tax rate reconciliation and (ii) income taxes paid disaggregated by jurisdiction.

The Company prospectively adopted ASU 2023-09 during the year ended December 31, 2025.

See Note 14 Income Taxes in the accompanying notes to the consolidated financial statements for further detail.

KINIKSA PHARMACEUTICALS, LTD.

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Short-term investments — U.S.

Treasury notes

Treasury Securities

Fair Value Measurements

1 unchanged sentence

Cash equivalents — money market funds

Cash equivalents — U.S.

Treasury notes

Short-term investments — U.S.

Treasury notes

Treasury Securities

During the years ended December 31, 2025 and 2024 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 December 31, 2024 and 2023 included U.S.

Treasury notes, which are not traded on a daily basis and, therefore, represent a Level 2 measurement in the fair value hierarchy at each period end.

Cash equivalents and short-term investments as of December 31, 2024 and 2023 consisted of U.S.

Treasury notes which investments were each due within six months of such date.

The Company’s cash equivalents and short-term investments as of December 31, 2025 and 2024 included United States 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:

Maturities within one year

Maturities after one year through five years

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The following tables summarize short-term investments:

December 31, 2025

Short-term investments — U.S.

Treasury notes

Treasury Securities

December 31, 2024

Cash equivalents — U.S.

Treasury notes

Short-term investments — U.S.

Treasury notes

Treasury Securities

As of December 31, 2025 and 2024 the Company considers the unrealized losses in their investment portfolio to be temporary in nature and not due to credit losses.

The Company has the ability to hold such investments until

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

recovery of the fair value.

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.

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Product Revenue, Net

Product revenue, net, from sales of ARCALYST was as follows:

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

Product Revenue, net

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The following tables summarizes balances and activity in each of the product revenue allowance and reserve categories for the years ended December 31, 2025 and 2024:

11 unchanged sentences

Balance at December 31, 2024

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Total revenue-related reserves as of December 31, 2025 and 2024, included in the Company’s consolidated balance sheets, are summarized as follows:

2 unchanged sentences

Total revenue-related reserves

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Inventory consisted of the following:

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Total inventory

As of December 31, 2025, $ 20,883 of semi-finished goods were associated with the Company’s technology transfer of ARCALYST drug substance manufacturing to a new facility, which is pending regulatory approval.

The Company believes it is probable that regulatory approval will be obtained, and all such inventory will be available for commercial distribution in the future.

Property and Equipment, Net

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Depreciation expense for the years ended December 31, 2025, 2024 and 2023 was $ 196 , $ 448 and $ 1,109 , respectively.

As of December 31, 2024 and 2023, $ 99 and $ 122 , respectively, of the Company’s property and equipment, net was in the United Kingdom.

KINIKSA PHARMACEUTICALS, LTD.

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Accrued expenses consisted of the following:

Accrued research and development expenses

Accrued employee compensation and benefits

Accrued inventory and manufacturing

Accrued research and development expenses

Accrued legal, commercial and professional fees

Total accrued expenses

During the year ended December 31, 2022, the Company recorded an out of period adjustment of $ 2,223 that primarily related to a decrease in accrued research and development expenses to correct immaterial errors that originated in prior periods.

The Company evaluated the materiality of the adjustments to prior-period annual and interim financial statements and the current period, and concluded the effect of the adjustments were immaterial to all periods.

Ordinary Shares

3 unchanged sentences

Each Class B ordinary share entitles the holder to ten votes on all matters submitted to the shareholders for a vote.

The holders of Class A and Class B ordinary shares, voting together as a single class, are entitled to elect the directors of the Company.

Holders of Class A1 ordinary shares and Class B1 ordinary shares have no voting rights.

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

The holders of Class A and Class B ordinary shares, voting together as a single class, are entitled to elect the directors of the Company.

Holders of Class A1 ordinary shares and Class B1 ordinary shares have no voting rights.

The Company’s ordinary shareholders are entitled to receive dividends, as may be declared by the Company’s board of directors.

8 unchanged sentences

In connection with the Redomiciliation, Kiniksa Bermuda was issued with one ordinary share with a nominal value of £ 0.01 per share (the “KNSA Bermuda Ordinary Share”) and 50,000 redeemable preference shares with a nominal value of £ 1.00 per share (the “KNSA Bermuda Preference Shares”) in the capital of Kiniksa International in order to satisfy the initial authorized minimum capital requirements for an English public company which is currently prescribed as GBP£ 50,000 .

In the year ending December 31, 2025, it is expected that:

(i) the KNSA Bermuda Ordinary Share will be gifted to Kiniksa International for nil consideration;

and (ii) the KNSA Bermuda Preference Shares will be redeemed in order to remove Kiniksa Bermuda as a shareholder of Kiniksa International.

In the year ended December 31, 2025, (i) the KNSA Bermuda Ordinary Share was gifted to Kiniksa International for nil consideration;

and (ii) the KNSA Bermuda Preference Shares were redeemed in order to remove Kiniksa Bermuda as a shareholder of Kiniksa International.

The KNSA Bermuda Preference Shares have no rights to vote at any general meeting of Kiniksa International and have no right to receive any dividend.

The rights and restrictions attaching to the Existing Preference Shares and KNSA Bermuda Ordinary Share are set out in the articles of association of Kiniksa International.

As of December 31, 2025 there are no KNSA Bermuda Ordinary Shares or KNSA Bermuda Preference Shares in issue.

In November 2025, Kiniksa Bermuda was liquidated as part of the completion of the Redomiciliation.

Share-Based Compensation

As part of the Redomiciliation, Kiniksa International assumed the sponsorship of, and all rights and obligations of Kiniksa Bermuda under Kiniksa Bermuda’s equity compensation plans, which include the 2018 Plan, the 2015 Plan, the 2018 ESPP and the RLTIP (each as defined below).

2018 Incentive Award Plan

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A total of 4,466,500 Class A ordinary shares were initially reserved for issuance under the 2018 Plan.

The number of Class A ordinary shares that may be issued under the 2018 Plan will automatically increase on each January 1, beginning in 2019 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2028, equal to the lesser of (1) 4 % of the Class A ordinary shares outstanding (on an as-converted basis)

KINIKSA PHARMACEUTICALS, LTD.

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(Amounts in thousands, except share and per share amounts)

on the final day of the immediately preceding calendar year and (2) a smaller number of Class A ordinary shares determined by the Company’s board of directors.

determined by the Company’s board of directors.

As of December 31, 2025, 5,621,352 shares remained available for future grant.

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(Amounts in thousands, except share and per share amounts)

Restricted Share Units

RSUs represent the right to receive shares of the Company’s Class A ordinary shares upon vesting of the RSUs.

The fair value of each RSU award is based on the closing price of the Company’s Class A ordinary shares on the date of grant.

Starting March 2021, the Company granted RSUs with service conditions (“Time-Based RSUs”) to eligible employees.

The Time-Based RSUs 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 Shares Units

In the second quarter of 2024, the Company began periodically granting performance-based restricted share units to certain employees under the 2018 Plan.

The Company granted awards which are earned based upon the achievement of certain specified ARCALYST revenue targets (“Revenue PSUs”), and awards which are earned based upon the Company’s total shareholder return (“TSR”) relative to the performance of the members of the Nasdaq Biotechnology Index (“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.

The following table summarizes RSU and PSU activity for the year ended December 31, 2025:

Unvested as of December 31, 2024

Unvested RSUs as of December 31, 2025

RSUs granted in 2024 and 2023 had weighted average grant date fair values of $ 22.19 and $ 15.13 , respectively.

PSUs granted in 2024 had a weighted average grant date fair value of $ 22.06 .

No PSUs were granted in 2023.

The total grant date fair values of RSUs that vested during the years ended December 31, 2025, 2024, and 2023 totaled $ 12,576 , $ 9,495 and $ 5,635 , respectively.

No PSUs vested during the years ended December 31, 2025, 2024 and 2023.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Share Options

6 unchanged sentences

The aggregate intrinsic value of share options is calculated as the difference between the exercise price of the share options and the fair value of the Company’s ordinary shares for those share options that had exercise prices lower than the fair value of the Company’s ordinary shares.

During the year ended December 31, 2024, share option holders exercised 1,520,347 share options for Class A ordinary shares with an intrinsic value of $ 19,235 for total cash proceeds to the Company of $ 16,260 .

During the year ended December 31, 2023, share option holders exercised 319,829 share options for Class A ordinary shares with an intrinsic value of $ 2,595 for total cash proceeds to the Company of $ 2,876 .

During the year ended December 31, 2022, share option holders exercised 383,106 share options for Class A ordinary shares with an intrinsic value of $ 2,196 for total cash proceeds to the Company of $ 2,606 .

The total intrinsic value of options exercised during the years ended December 31, 2025, 2024 and 2023, were $ 63,241 , $ 19,235 and $ 2,595 , respectively.

The tax benefit arising on the exercise of stock options was $ 16,481 for the year ended December 31, 2025.

The weighted-average grant-date fair value per share of share options granted during the years ended December 31, 2025, 2024 and 2023 was $ 17.61 , $ 14.41 and $ 9.82 , respectively.

The total fair value of share options vested during the years ended December 31, 2024, 2023 and 2022 was $ 18,161 , $ 19,036 and $ 21,229 , respectively.

As of December 31, 2024, total unrecognized compensation expense related to the unvested share option awards was $ 37,910 which is expected to be recognized over a weighted average remaining period of 2.44 years.

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.

Outstanding as of December 31, 2024

Outstanding as of December 31, 2025

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

No PSOs were exercised during the years ended December 31, 2025, 2024 and 2023.

The weighted-average grant-date fair value per share of PSOs granted during the years ended December 31, 2025 was $ 14.17 .

No PSOs were granted during the years ended December 31, 2024 and 2023.

Option Valuation

5 unchanged sentences

During the years ended December 31, 2025, 2024 and 2023, the Company did not grant share options to non-employees.

Restricted Share Units

RSUs represent the right to receive shares of the Company’s Class A ordinary shares upon vesting of the RSUs.

The fair value of each RSU award is based on the closing price of the Company’s Class A ordinary shares on the date of grant.

Starting March 2021, the Company granted RSUs with service conditions (“Time-Based RSUs”) to eligible employees.

The Time-Based RSUs vest 25 % on each of the first, second, third and fourth anniversaries of the date of grant, subject to continued employment through such dates.

Rilonacept Long-Term Incentive Plan

In December 2019, the compensation committee of the Company’s board of directors approved the Company’s Rilonacept Long-Term Incentive Plan (“RLTIP”) under the Company’s 2018 Plan to incentivize eligible employees of the Company or any of its subsidiaries to achieve FDA approval for the commercial sale and marketing of ARCALYST for the treatment of recurrent pericarditis in the United States (“RLTIP Milestone”).

The RLTIP provided for eligible employees to receive a cash award and two grants of RSU awards covering Class A ordinary shares under the 2018 Plan.

The cash award was eligible to be earned and paid upon the date the RLTIP Milestone was achieved (the “Achievement Date”) with respect to an amount determined in accordance with the RLTIP based on the earnout percentage.

The number of Class A ordinary shares issuable under the first RSU award (“First RSU Award”) as a result of the achievement of the RLTIP Milestone was determined in accordance with the RLTIP based on the earnout percentage, and such RSUs vested on the first anniversary of the Achievement Date, subject to continued employment on such date.

The second RSU award was granted on the Achievement Date with respect to a number of shares determined in accordance with the RLTIP, based on both the earnout percentage and the upside earnout percentage, and vested on the second anniversary of the Achievement Date, subject to continued employment on such date.

During the years ended December 31, 2020 and 2019, the Company granted the First RSU Awards as part of the RLTIP to eligible employees.

During the year ended December 31, 2021, the RLTIP Milestone was achieved and 187,682 of Class A ordinary shares were issued under the First RSU Awards in accordance with the RLTIP and vested in one installment in March 2022 (on the first anniversary of the Achievement Date).

During the year ended December 31, 2021, the Second RSU Awards were granted to eligible employees on the Achievement Date with 142,283 shares granted in accordance with the RLTIP which vested in one installment in March 2023.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

For the years ended December 31, 2024, 2023 and 2022, the Company recognized $ 11,090 , $ 7,822 and $ 4,246 , respectively in compensation expense related to RSUs including those granted in connection with the RLTIP.

The following table summarizes RSU activity, including the Time-Based RSUs and the RSU Awards under the RLTIP, for the year ended December 31, 2024:

Unvested RSUs as of December 31, 2023

Unvested RSUs as of December 31, 2024

As of December 31, 2024, total unrecognized compensation cost related to the RSU Awards and Time-Based RSUs was $ 32,544 which is expected to be recognized over a weighted average remaining period of 2.57 years.

Market and Performance-Based Shares Units

In the second quarter of 2024, the Company began periodically granting performance-based restricted share units to certain employees under the 2018 Plan.

The PSUs are subject to a three year service period.

The following table summarizes PSU activity for the year ended December 31, 2024:

Unvested PSUs as of December 31, 2023

Unvested PSUs as of December 31, 2024

As of December 31, 2024, total unrecognized compensation cost related to the PSU awards was $ 1,268 which is expected to be recognized over a weighted average remaining period of 2.00 years.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

As of December 31, 2025, total unrecognized compensation cost related to RSUs, Revenue PSUs, TSR PSUs, and share options was $ 90,372 which is expected to be recognized over a weighted average remaining period of 2.52 years.

As of December 31, 2025, total unrecognized compensation cost related to outstanding Development PSUs and PSOs was $ 9,576 which will be recognized when the applicable milestones are deemed probable of achievement through the date the awards vests with a cumulative catch-up.

Share-Based Compensation

3 unchanged sentences

Selling, general and administrative expenses

Total stock-based compensation

Share-based compensation expense included in total operating expenses

The tax benefit from share-based compensation recognized during the years ended December 31, 2025, 2024 and 2023, were $ 9,643 , $ 7,976 and $ 7,433 , respectively.

Out-Licensing Agreements

1 unchanged sentence

In August 2022, the Company entered into a license agreement (the “Genentech License Agreement”) with Genentech, Inc.

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”).

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

(each, a “Genentech Licensed Product”).

The Genentech License Agreement became effective in September 2022 (the “Genentech Effective Date”) following termination of the statutory waiting period under the Hart-Scott Rodino Act.

1 unchanged sentence

During the year ended December 31, 2023, the Company received cash payments of $ 20,000 following delivery of certain drug supplies to Genentech and $ 15,000 following Genentech’s achievement of a development milestone related to a new indication under the Genentech License Agreement.

In the fourth quarter of 2023, following the achievement of a development milestone related to a second indication under the Genentech License Agreement, Genentech became obligated to make an additional cash payment of $ 10,000 which the Company received in 2024.

In the second quarter of 2024, the Company received a cash payment of $ 5,000 following the achievement of a development milestone related to the third indication under the Genentech License Agreement.

In 2023, following the achievement of a development milestone related to a second indication under the Genentech License Agreement, Genentech became obligated to make an additional cash payment of $ 10,000 which the Company received in 2024.

In 2024, the Company received a cash payment of $ 5,000 following the achievement of a development milestone related to the third indication under the Genentech License Agreement.

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 December 31, 2025.

4 unchanged sentences

Under the Genentech License Agreement, Genentech has the right to assume manufacturing responsibilities for Genentech Licensed Products.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Absent early termination, the Genentech License Agreement will continue until there are no more royalty or other payment obligations owed to the Company.

9 unchanged sentences

The Company also evaluated whether certain options outlined within the Genentech License Agreement represented material rights that would give rise to a performance obligation, including the option to purchase additional drug substance, and concluded that none of the options convey a material right to Genentech and therefore are not considered separate performance obligations within the Genentech License Agreement.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The Company assessed the above promises and determined that the exclusive license for vixarelimab is reflective of a vendor-customer relationship and therefore represents a performance obligation.

5 unchanged sentences

The Company determined that the $ 20,000 variable consideration related to the delivery of the initial drug supply and drug product resupply was no longer constrained during the fourth quarter of 2022, as the Company determined that it could assert it was not probable that a significant reversal in the amount of cumulative revenue recognized would occur.

The Company met the milestone obligation in the first quarter of 2023 and invoiced Genentech for the related $ 20,000 payment for the delivery of certain drug material.

The Company met the milestone in 2023 and invoiced Genentech for the related $ 20,000 payment for the delivery of certain drug material.

In 2023 and 2024, the Company added $ 25,000 and $ 5,000 , respectively, to the transaction price following Genentech’s achievement of development milestones under the Genentech License Agreement.

7 unchanged sentences

and (iv) completion of the Phase 2b clinical trial for vixarelimab.

The selling price of each performance

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

obligation in the Genentech License Agreement was determined based on the Company’s standalone selling price (“SSP”) 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 selling price of each performance obligation in the Genentech License Agreement was determined based on the Company’s standalone selling price (“SSP”) 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.

13 unchanged sentences

Revenue is recorded as a percentage of the allocated transaction price times the percent of completion.

The Company recognized no collaboration revenue during the year ended December 31, 2025.

The Company recognized $ 5,261 and $ 37,083 of collaboration revenue during the years ended December 31, 2024 and 2023, respectively, under the Genentech License Agreement related to the license, completed portion of the Phase 2b clinical trial for vixarelimab, and materials delivered.

As a result of the $ 5,000 in development milestones achieved by Genentech, the Company recognized revenue of $ 4,989 , during the year ended December 31, 2024, related to performance obligations satisfied in prior periods.

As a result of the $ 5,000 in development milestones achieved by

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Genentech, the Company recognized revenue of $ 4,989 , during the year ended December 31, 2024, related to performance obligations satisfied in prior periods.

The remaining revenue was recognized as a result of the completed portion of the Phase 2b clinical trial for vixarelimab.

As of December 31, 2024, the Company has recognized as revenue all of the transaction price associated with the Genentech License Agreement.

The Company completed its obligation for the Phase 2b clinical trial for vixarelimab during the year ended December 31, 2024.

As such, the Company has recognized all revenue allocated to the completion of the Phase 2b clinical trial for vixarelimab performance obligation as of the end of the year ended December 31, 2024.

Huadong Collaboration Agreements

3 unchanged sentences

The Company otherwise retained its current rights to the Huadong Licensed Products outside the Huadong Territory.

In February 2025, the Company provided written notice to Huadong that Huadong has not conducted material development activity with respect to mavrilimumab in the People’s Republic of China for a continuous period in excess of six months as required under the mavrilimumab Huadong Collaboration Agreement.

Unless Huadong conducts material development activity within a prescribed time period, the mavrilimumab Huadong Collaboration Agreement will terminate on April 25, 2025.

The Company does not expect to record any significant charges related to the termination of the mavrilimumab Huadong Collaboration Agreement.

In April 2025, the Company and Huadong entered into a mutual termination agreement pursuant to which the parties agreed to terminate the mavrilimumab Huadong Collaboration Agreement and release all claims related thereto.

The ARCALYST Huadong Collaboration Agreement remains in effect.

Under the Huadong Collaboration Agreements, the Company received a total upfront cash payment of $ 22,000 , which included $ 12,000 for the Huadong Territory license of ARCALYST and $ 10,000 for the Huadong Territory license of mavrilimumab.

1 unchanged sentence

The Company will be eligible to receive up to approximately $ 50,000 in contingent sales-based milestone payments for ARCALYST, all of which remain as of December 31, 2025.

Due to its termination, the Company does not expect to

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

receive any future payments under the mavrilimumab Huadong Collaboration Agreement.

The Company was eligible to receive up to approximately $ 576,000 in payments for mavrilimumab, including specified development, regulatory and sales-based milestones, all of which remained as of December 31, 2024.

Huadong was also obligated to pay the company tiered percentage royalties ranging from mid-teens to low twenties on annual net sales of mavrilimumab in the Huadong territory.

Due to its termination, the Company does not expect to receive any future payments under the mavrilimumab Huadong Collaboration Agreement.

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.

4 unchanged sentences

The Company will supply certain materials to support development and commercialization activities for ARCALYST.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Absent early termination, the ARCALYST Huadong Collaboration Agreement will continue on a country-by-country or region-by-region basis until there are no more royalty payments owed to the Company in such country or region.

5 unchanged sentences

The Company concluded that the Huadong Collaboration Agreements should not be combined and treated as a single arrangement for accounting purposes as the Huadong Collaboration Agreements were negotiated separately with separate and distinct commercial objectives, the amount of consideration in one Huadong Collaboration Agreement is not dependent on the price or performance of the other Huadong Collaboration Agreement, and the goods and services promised in the Huadong Collaboration Agreements are not a single performance obligation.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Accounting for Mavrilimumab Huadong Collaboration Agreement

1 unchanged sentence

delivery of (i) exclusive license for mavrilimumab in the Huadong Territory and (ii) clinical manufacturing supply of certain materials for mavrilimumab products in the Huadong Territory.

The Company also evaluated whether certain options outlined within the mavrilimumab Huadong Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options convey a material right to Huadong and therefore are not considered separate performance obligations within the mavrilimumab Huadong Collaboration Agreement.

The Company assessed the above promises and determined that the exclusive license for mavrilimumab in the Huadong Territory is reflective of a vendor-customer relationship and therefore represents a performance obligation.

The exclusive license for mavrilimumab in the Huadong Territory is considered functional intellectual property and distinct from other promises under the Huadong Collaboration Agreement as Huadong can benefit from the license on its own or together with other readily available resources and the license is separately identifiable from the other promises.

The clinical manufacturing supply of certain materials for mavrilimumab products in the Huadong Territory is considered distinct from the exclusive license for mavrilimumab as Huadong can benefit from the manufacturing services together with the license transferred by the Company at the inception of the Huadong Collaboration Agreement.

Therefore, each represents a separate performance obligation within a contract with a customer at contract inception.

The Company determined the transaction price at the inception of the mavrilimumab Huadong Collaboration Agreement which includes $ 10,000 , consisting of the upfront payment.

The Company also includes an estimate of variable consideration associated with the clinical manufacturing supply of certain materials when those materials are shipped.

The Company determined that any variable consideration related to development and regulatory milestones is 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.

The Company also determined that royalties and sales milestones relate solely to the licenses 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.

As noted above, the Company identified two performance obligations in the mavrilimumab Huadong Collaboration Agreement:

(i) the delivery of the exclusive license for mavrilimumab in the Huadong Territory;

and (ii) the clinical manufacturing supply of certain materials for mavrilimumab products in the Huadong Territory.

The selling price of each performance obligation in the mavrilimumab Huadong Collaboration Agreement was determined based on the Company’s standalone selling price (“SSP”) 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 variable consideration related to the manufacturing obligations to the future clinical supply of mavrilimumab products in the Huadong Territory and the remaining fixed and variable consideration to the license obligation.

The Company recognizes revenue for the license performance obligations at a point in time, that is upon transfer of the license to Huadong.

The Company also included an estimate of variable consideration associated with the clinical manufacturing supply of certain materials when those materials were shipped.

The Company recognized revenue for the license performance obligations at a point in time, that is upon transfer of the license to Huadong.

As control of the license was transferred on the Effective Date and Huadong could begin to use and benefit from the license, the Company recognized $ 10,000 of collaboration revenue during the year ended December 31, 2022, under the mavrilimumab Huadong Collaboration Agreement.

The Company will recognize revenue for the clinical manufacturing supply obligations at a point in time, that is upon each delivery of the supply to Huadong.

The Company has no t recognized any revenue under the mavrilimumab Huadong Collaboration Agreement for the years ended December 31, 2024 and 2023 as there has been no delivery of clinical manufacturing supply of certain materials under the mavrilimumab Huadong Collaboration Agreement to date.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Due to the termination of the mavrilimumab Huadong Collaboration Agreement in April 2025, the Company will not recognize any additional revenue from that agreement.

Accounting for ARCALYST Huadong Collaboration Agreement

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and (iii) commercial manufacturing supply of certain material for ARCALYST products in the Huadong Territory.

The Company also evaluated whether certain options outlined within the ARCALYST Huadong Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options convey a material right to Huadong and therefore are not considered separate performance obligations within the ARCALYST Huadong Collaboration Agreement.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

options convey a material right to Huadong and therefore are not considered separate performance obligations within the ARCALYST Huadong Collaboration Agreement.

The Company assessed the above promises and determined that there is one combined performance obligation for the exclusive license for ARCALYST and clinical and commercial manufacturing obligations for ARCALYST products in the Huadong Territory.

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This estimate considers the timing of development and commercial activities under the ARCALYST Huadong Collaboration Agreement and may be reduced or increased based on changes in the various activities.

The Company recognized $ 189 of the transaction price in collaboration revenue during the year ended December 31, 2024, under the ARCALYST Huadong Collaboration Agreement related to materials delivered.

The Company has no t recognized any revenue under the ARCALYST Huadong Collaboration Agreement for the years ended December 31, 2025 and 2023 as there were no deliveries of materials under the ARCALYST Huadong Collaboration Agreement.

As of December 31, 2025, $ 31,811 is recorded in non-current deferred revenue, based upon timing of anticipated future shipments.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The following tables summarizes the Company’s contract assets and contract liabilities in connection with license and collaboration agreements for the years ended December 31, 2025 and 2024:

4 unchanged sentences

Contract Liabilities:

Genentech vixarelimab

Huadong ARCALYST

Total Contract Liabilities

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Balance at End

2 unchanged sentences

Year ended December 31, 2024

Contract Assets:

Genentech vixarelimab

Contract Liabilities:

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Additionally, the Company could be obligated to make up to an aggregate of up to $ 150,000 of payments upon the achievement of specified annual net sales milestones and to pay tiered royalties on escalating tiers of annual net sales of licensed products starting in the high single-digit percentages and ending below the teens.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The Company also agreed to pay certain obligations under third party contracts retained by Biogen that relate to the vixarelimab program.

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In addition, the tiered royalty rates to be paid by the Company to Biogen increased by an amount equal to less than one percent.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Upon the termination or expiration of the Genentech License Agreement, the amendments to the terms of the Biogen Agreement, as set forth in the Second Biogen Amendment, will terminate and all terms of the Biogen Agreement will revert to the version of such terms in effect as of immediately prior to the effective date of the Genentech License Agreement.

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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

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

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 CAPS and DIRA in the United States.

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 CAPS and DIRA in the United States.

The Company has made $ 32,500 in payments under the Regeneron Agreement in connection with upfront fees and achievement of regulatory milestones, including a $ 20,000 payment in the first quarter of 2021 in connection with the achievement of a regulatory milestone.

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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

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

or other disposition of rights with respect to ARCALYST, including upfront payments, milestone payments and royalties.

For the years ended December 31, 2025, 2024 and 2023, the Company recognized $ 229,545 , $ 127,375 and $ 56,524 respectively, of expenses related to the profit sharing agreement presented within collaboration expenses.

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In December 2017, the Company entered into a license agreement (as amended from time to time, the “MedImmune Agreement”) with MedImmune, Limited (subsequently acquired by AstraZeneca PLC) (“MedImmune”), pursuant to which MedImmune granted the Company an exclusive, sublicensable, worldwide license to certain intellectual property rights to make, use, develop and commercialize mavrilimumab.

Under the MedImmune Agreement,

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

the Company also acquired reference rights to relevant manufacturing and regulatory documents and MedImmune’s existing supply of mavrilimumab drug substance and product.

Under the MedImmune Agreement, the Company also acquired reference rights to relevant manufacturing and regulatory documents and MedImmune’s existing supply of mavrilimumab drug substance and product.

The Company was obligated to use commercially reasonable efforts to develop and commercialize the licensed products.

In February 2025, the Company delivered a notice of termination to MedImmune, notifying them of its intent to terminate the MedImmune Agreement, for convenience, effective May 22, 2025.

Following such date, the exclusive worldwide sublicense rights to certain intellectual property rights to make, use, develop and commercialize mavrilimumab will be returned to MedImmune.

The Company does not expect to record any significant charges related to the termination of the MedImmune Agreement.

In exchange for these rights, the Company made an upfront payment of $ 8,000 .

The Company accounted for the acquisition of technology as an asset acquisition because it did not meet the definition of a business.

The Company recorded the upfront payment as research and development expense in the consolidated statement of operations and comprehensive income (loss) because the acquired technology represented in-process research and development and had no alternative future use.

Under the terms of the MedImmune Agreement, the Company was obligated to make clinical, regulatory and initial sales milestone payments of up to $ 72,500 in aggregate for the first two indications, including, a $ 5,000 pass-through payment due upon the achievement of a specified clinical milestone event which was achieved in the fourth quarter of 2018.

Also included was a milestone payment of $ 10,000 due upon the earlier to occur of a specified regulatory milestone and December 31, 2018.

During the year ended December 31, 2019, the Company made both the $ 5,000 and $ 10,000 previously accrued milestone payments in accordance with the MedImmune Agreement.

In addition, the Company was obligated to make clinical and regulatory milestone payments of up to $ 15,000 in the aggregate for each subsequent indication.

In July 2020, the Company entered into an amendment to the MedImmune Agreement to establish a new coronavirus field and defer the payment of certain development and regulatory milestones as applied to the new coronavirus field.

Following such date, the exclusive worldwide sublicense rights to certain intellectual property rights to make, use, develop and commercialize mavrilimumab were returned to MedImmune.

The Company did no t record any significant charges related to the termination of the MedImmune Agreement.

During the years ended December 31, 2025, 2024 and 2023, the Company did no t record expenses in connection with milestone payments due under the MedImmune Agreement.

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Following the Redomiciliation, the Company is incorporated and principally subject to taxation in the United Kingdom.

Under the current laws of Bermuda, tax on a company’s income is assessed at a zero percent tax rate.

As a result, the Company has no t recorded any income tax benefits from its losses incurred in Bermuda during the reporting periods in which it was incorporated there, and no net operating loss carryforwards will be available to the Company for those losses.

Following the Redomiciliation, the Company’s income is subject to the enacted United Kingdom statutory corporate tax rate and net operating losses incurred have an indefinite carryforward.

The Company’s wholly owned U.S.

subsidiaries, Kiniksa US and Primatope, are subject to federal and state income taxes in the United States.

The Company’s wholly owned subsidiary Kiniksa Bermuda remains subject to taxation, if any, in Bermuda.

Certain of the Company’s subsidiaries operate under cost plus arrangements.

Since 2021, the Company has engaged in a series of intra-entity asset transfers and allocations to contribute assets to its wholly owned Switzerland subsidiary, UK subsidiary and its UK Swiss branch office.

In January 2021, in connection with its launch readiness activities, Kiniksa Bermuda contributed all of its rights, title and interest in, among other things, certain contracts (including the Regeneron Agreement), intellectual

Under the previous laws of Bermuda, tax on a company’s income is assessed at a zero percent tax rate.

As a result, the

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

property rights, product filings and approvals and other information, plans and materials owned or controlled by Kiniksa Bermuda insofar as they related exclusively or primarily to ARCALYST to Kiniksa UK.

In February 2022, Kiniksa Bermuda contributed its exclusive rights to develop and commercialize mavrilimumab in the Huadong Territory to Kiniksa UK.

In July 2022, Kiniksa Bermuda contributed all of its rights, title and interest in, among other things, certain contracts (including the Biogen Agreement), intellectual property rights, product filings and approvals and other information, plans and materials owned or controlled by Kiniksa Bermuda insofar as they related exclusively or primarily to vixarelimab to Kiniksa UK.

The consolidated Company did not incur tax liabilities on any of these intra-entity transfers since the transferor, Kiniksa Bermuda, is exempt from income tax in Bermuda, its jurisdiction of incorporation.

Kiniksa UK accounted for the 2021 and 2022 intra-entity transfers as transfers of assets between related parties and received stepped up tax bases in the contributed intellectual property assets, equal to the fair value of the assets at the time of transfer.

The Company recorded UK deferred tax assets as a result of these contributions, which represent the difference between the stepped-up tax bases and the book bases for financial statement purposes.

At the time of the 2021 and 2022 transfers of the relevant assets, the Company recorded a valuation allowance on the full amount of the recognized deferred tax assets.

The fair value of the January 2021 transfer of ARCALYST intellectual property assets was determined utilizing forecasted cash flows attributable to commercial operations and estimated probabilities of success of such cash flows, discounted to present value utilizing the discounted cash flow method.

The fair values of the transferred mavrilimumab and vixarelimab intellectual property assets were determined utilizing future cash flows related to agreements with third parties for the use of the applicable intellectual property and estimated probabilities of success of such cash flows, discounted to present value utilizing the discounted cash flow method.

Company has no t recorded any income tax benefits from its losses incurred in Bermuda during the reporting periods in which it was incorporated there, and no net operating loss carryforwards will be available to the Company for those losses.

Following the Redomiciliation, the Company’s income is subject to the enacted United Kingdom statutory corporate tax rate and net operating losses incurred have an indefinite carryforward.

The Company’s wholly owned United States subsidiaries, Kiniksa US and Primatope, are subject to federal and state income taxes in the United States.

The Company’s wholly owned subsidiary Kiniksa Bermuda remained subject to taxation, if any, in Bermuda for the period of time prior to its liquidation in November 2025.

Certain of the Company’s subsidiaries operate under cost plus intercompany arrangements.

The Company has engaged in a series of intra-entity asset transfers and allocations to contribute assets to its wholly owned Switzerland subsidiary and Kiniksa UK’s Swiss branch office.

In December 2023, Kiniksa UK allocated all of its rights, title and interest in, among other things, certain contracts (including the Regeneron Agreement), intellectual property rights, product filings and approvals and other information, plans and inventory owned or controlled by the Company insofar as they related exclusively or primarily to ARCALYST to Kiniksa UK’s Swiss branch office.

4 unchanged sentences

The fair value of the ARCALYST inventory was determined utilizing the average net selling price less estimated costs to sell.

In January 2024, Kiniksa Bermuda transferred to Kiniksa Switzerland all rights, title and interest in, among other things, certain contracts, intellectual property rights, product filings and approvals and other information, plans and materials owned insofar as they related exclusively or primarily to abiprubart, mavrilimumab, KPL-387 and certain preclinical assets, excluding certain rights necessary for the completion of Cohort 4 of the Company’s ongoing Phase 2 clinical trial of abiprubart in rheumatoid arthritis .

In June 2024, Kiniksa UK terminated its exclusive rights to develop and commercialize mavrilimumab in the Huadong Territory, with such rights reverting to Kiniksa Switzerland.

Thereafter Kiniksa Switzerland held worldwide rights to develop and commercialize mavrilimumab.

In October 2024, Kiniksa UK contributed all of its rights, title and interest in, among other things, certain contracts (including the Biogen Agreement), intellectual property rights, product filings and approvals and other information, plans and materials owned or controlled by Kiniksa UK insofar as they related exclusively or primarily to vixarelimab to Kiniksa Switzerland.

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The consolidated Company did not incur tax liabilities on any of the January 2024 intra-entity transfers since the transferor, Kiniksa Bermuda, is exempt from income tax in Bermuda.

Kiniksa Switzerland accounted for the intra-entity transfers as transfers of assets between related parties and received stepped up tax bases in the contributed intellectual property assets, equal to the fair value of the assets at the time of transfer.

In relation to the June 2024 transaction, Kiniksa UK received consideration in exchange for the termination of exclusive rights.

Neither Kiniksa UK nor Kiniksa Switzerland incurred any tax liabilities as a result of the transaction.

The consolidated Company did not incur tax liabilities on any of the October 2024 intra-entity transfers since the transferor, Kiniksa UK, is the sole direct shareholder of Kiniksa Switzerland.

2 unchanged sentences

The Company recorded deferred tax assets as a result of these contributions, which represent the difference between the stepped-up tax bases and the book bases for financial statement purposes.

Subsequent to the contribution there was a triggering event resulting in decreases to the tax asset balance related to mavrilimumab intangible assets.

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 (loss) before benefit (provision) for income taxes consisted of the following:

(1) As a result of the redomiciliation the Company’s year ended December 31, 2024 domestic operations refer to the UK and years ended December 31, 2023 and 2022 domestic operations refer to Bermuda

(2) As a result of the redomiciliation the Company’s year ended December 31, 2024 foreign operations include U.S., Germany, France, Switzerland and Bermuda, and years ended December 31, 2023 and 2022 foreign operations include U.S., UK, Germany, France, and Switzerland.

KINIKSA PHARMACEUTICALS, LTD.

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(Amounts in thousands, except share and per share amounts)

On July 4, 2025, new United States tax legislation was signed into law (known as the "One Big Beautiful Bill Act" or "OBBBA") which makes permanent many of the tax provisions enacted in 2017 as part of the Tax Cuts and Jobs Act that were set to expire at the end of 2025.

In addition, the OBBBA makes changes to certain United States corporate tax provisions, but many are generally not effective until 2026.

The Company continues to assess the impact of the tax provisions of the OBBBA on its consolidated financial statements, the Company currently believes that the tax provisions of the legislation are not expected to have a material impact on its operations.

Income (loss) before benefit (provision) for income taxes consisted of the following:

(1) As a result of the redomiciliation the Company’s years ended December 31, 2025 and 2024 domestic operations refer to the UK and the year ended December 31, 2023 domestic operations refer to Bermuda

(2) As a result of the redomiciliation the Company’s years ended December 31, 2025 and 2024 foreign operations include the United States, Switzerland, Germany, France and Bermuda, and the year ended December 31, 2023 foreign operations include the United States, UK, Switzerland, Germany and France.

The components of the Company’s income tax benefit (provision) were as follows:

Current income tax benefit (provision):

United States federal

United States state

Total current income tax benefit (provision)

Deferred income tax benefit (provision):

United States federal

United States state

Total deferred income tax benefit (provision)

Total benefit (provision) for income taxes

(1) As a result of the redomiciliation the Company’s year ended December 31, 2024 domestic operations refer to the UK and years ended December 31, 2023 and 2022 domestic operations refer to Bermuda

A reconciliation of the statutory income tax rate of the Company’s effective income tax rate is as follows:

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NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

A reconciliation of the statutory income tax rate of the Company’s effective income tax rate for the year ended December 31, 2025, after the adoption of ASU 2023-09 for 2025 is as follows:

December 31, 2025

United Kingdom Statutory Tax Rate

Foreign Tax Effects

United States

Statutory tax rate difference between United States and United Kingdom

State and local income taxes (1)

Research and development tax credits

Share-based compensation

Statutory tax rate difference between Switzerland and United Kingdom

Cantonal income taxes

Change in valuation allowance

Enacted changes in tax laws or rates

Other foreign jurisdictions

Changes in Unrecognized Tax Benefits

Other Adjustments

Effective income tax rate

(1) State taxes in Massachusetts made up the majority of the tax effect in this category.

A reconciliation of the statutory income tax rate of the Company’s effective income tax rate for the years ended December 31, 2024 and 2023, prior to the adoption of ASU 2023-09 were as follows:

Statutory income tax rate (1)

and Europe tax rate differential

United States and Europe tax rate differential

Research and development tax credits

Share-based compensation

state taxes, net of federal

United States state taxes, net of federal

Foreign-Derived Intangible Income ("FDII")

Uncertain tax positions

13 unchanged sentences

Operating lease liability

Accrued expenses and other liabilities

Intangible assets

1 unchanged sentence

Net operating losses

Accrued expenses and other liabilities

Total deferred tax assets

2 unchanged sentences

Right of use asset

Depreciation and amortization

Accrued expenses and other liabilities

Net deferred tax assets

As of December 31, 2024, the Company had federal research and development tax credit carryforwards of approximately $ 808 available to reduce future tax liabilities, which begin to expire in 2045.

As of December 31 2023, the Company had no federal research and development tax credit carryforwards available to reduce future tax liabilities.

As of December 31, 2025 and 2024, the Company had United States federal research and development tax credit carryforwards of approximately $ 3,224 and $ 808 available to reduce future tax liabilities, respectively, which begin to expire in 2045.

As of December 31, 2025 and 2024, the Company had state research and development tax credit carryforwards of approximately $ 869 and $ 184 respectively, available to reduce future tax liabilities, which can be carried forward indefinitely.

As of December 31, 2024 and 2023 the Company had foreign net operating loss (NOLs) carryforwards of $ 66,990 and $ 1,128 respectively, available to reduce future tax liabilities.

As of December 31, 2024 the Company had domestic NOLs of $ 18,382 .

The Company had no domestic NOLs as of December 31, 2023.

The NOLs maybe carried forward and utilized, subject to local limitations.

As of December 31, 2025 and 2024 the Company had foreign net operating loss (NOL) carryforwards of $ 106,244 and $ 66,990 respectively, available to reduce future tax liabilities.

As of December 31, 2025 and 2024 the Company had UK domestic NOLs of $ 3,119 and $ 18,382 , respectively.

The NOLs may be carried forward and utilized, subject to local limitations.

As required by ASC 740 management regularly reassesses the valuation allowance on the Company’s deferred income tax assets.

2 unchanged sentences

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.

In the third quarter of 2022, the Company assessed the valuation allowance on its UK deferred tax assets and considered positive evidence, including, among other things, cumulative UK income in recent years, estimates of sales related to the Company’s commercial product ARCALYST, and future profitability by jurisdiction.

After assessing both the positive evidence and negative evidence, the Company determined it was more likely than not that its UK deferred tax assets would be realized in the future and released the associated valuation allowance during the year ended December 31, 2022.

This resulted in a non-cash deferred tax benefit of $ 185,495 .

As of December 31, 2022, the Company maintained a full valuation allowance against its U.S.

deferred tax assets.

The valuation allowance increased by $ 9,749 in 2025 primarily as a result of additional net operating losses of Kiniksa Switzerland.

The valuation allowance increased by $ 610,452 in 2024 primarily as a result of the establishment of the valuation allowance for the Kiniksa Switzerland deferred tax assets which primarily consisted of the tax basis in intellectual property transferred from Bermuda and net operating losses.

In the second quarter of 2023, the Company assessed the valuation allowance on its United States deferred tax assets and considered positive evidence, including cumulative United States income in recent years, primarily related to cost plus intercompany arrangements and expectations regarding future profitability.

The Company determined it was more likely than not that its United States deferred tax assets are realizable in the future and released the associated valuation allowance as of June 30, 2023.

KINIKSA PHARMACEUTICALS, LTD.

1 unchanged sentence

(Amounts in thousands, except share and per share amounts)

In the second quarter of 2023, the Company assessed the valuation allowance on its U.S.

deferred tax assets and considered positive evidence, including cumulative U.S.

income in recent years, primarily related to cost plus arrangements and expectations regarding future profitability.

The Company determined it was more likely than not that its U.S.

deferred tax assets are realizable in the future and released the associated valuation allowance as of June 30, 2023.

In the fourth quarter of 2023, the Company assessed the valuation allowance on its Kiniksa UK deferred tax assets and considered positive and negative evidence, including among other things, the impact of future profitability decreasing in the UK as a result of the allocation of ARCALYST to the Swiss branch office.

After assessing both the positive and negative evidence, the Company determined it was more likely than not that a portion of the UK deferred tax assets would not be realized in the future and established a partial valuation allowance on those assets during the year ended December 31, 2023.

In 2025, the Company reassessed the valuation allowance on its Kiniksa UK deferred tax assets.

After assessing both the positive and negative evidence, including but not limited to future profitability in the UK, the Company determined it was more likely than not that all the UK deferred tax assets would be realized in the future, and released the remaining partial valuation allowance on those assets.

The Company recognized a non-cash deferred tax benefit of $ 33,788 during the year ended December 31, 2023.

This benefit primarily resulted from the step up in basis of intangible assets and inventory received in Switzerland associated with the allocation of ARCALYST to the Swiss branch office and the release of the U.S.

valuation allowance.

This was partially offset by the establishment of a partial UK valuation allowance.

There are no material deferred tax assets in the jurisdictions outside the United States, UK and Switzerland.

Utilization of the state research and development tax credits may be subject to substantial annual limitation under Section 382 of the Internal Revenue Code of 1986 due to ownership changes that could occur in the future.

Utilization of the United States federal and state NOLs and research and development tax credits may be subject to substantial annual limitation under Section 382 of the Internal Revenue Code of 1986 due to ownership changes that could occur in the future.

These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income.

In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain shareholders or public groups in the shares of a corporation by more than 50% over a three-year period.

Changes in the valuation allowance for deferred taxes were as follows:

Valuation allowance at beginning of year

Increases recorded through the balance sheet

Decreases (increases) recorded to income tax provision

Valuation allowance at end of year

The valuation allowance increased by $ 26,676 in 2023 primarily as a result of the establishment of the valuation allowance for the UK deferred tax assets which primarily consisted of the tax basis in intellectual property transferred from Bermuda and net operating losses.

The Company recognizes the tax benefit from an uncertain tax position only if it is more-likely-than-not that the tax position will be sustained on examination by taxing authorities, based on the technical merits of the position.

1 unchanged sentence

The amount of unrecognized tax benefits is $ 32,675 , $ 13,390 and $ 1,794 as of December 31, 2025, 2024 and 2023, respectively.

The net change in 2024, 2023 and 2022 relate to tax positions on the Company’s intellectual property transfers and positions on research and development credits.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The net change in 2025, 2024 and 2023 relate to tax positions on the Company’s intellectual property transfers.

As of December 31, 2025, the Company had a liability of $ 32,675 for unrecognized tax benefits of which, $ 19,214 , if recognized, would reduce the effective tax rate.

A roll forward of the Company’s uncertainties in its income tax provision liability is presented below:

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The Company’s policy is to record interest and penalties related to income taxes as part of its income tax provision.

The Company had recorded immaterial interest on the tax positions during the year ended December 31, 2024, 2023 and 2022.

The Company files U.S.

federal income tax returns and income tax returns in various state, local and foreign jurisdictions.

The Company’s income tax returns are subject to tax examinations for the tax years ended December 31, 2021 and subsequent years.

The Company has accrued $ 1,117 at year end December 31, 2025 and immaterial interest and penalties on the tax positions during the year ended December 31, 2024 and 2023.

The Company files United States federal income tax returns and income tax returns in various state, local and foreign jurisdictions.

The Company’s income tax returns are subject to tax examinations for the tax years ended

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

December 31, 2022 and subsequent years.

His Majesty’s Revenue and Customs (“HMRC”) commenced an examination of the Company’s 2023 and 2024 UK corporate income tax returns.

At December 31, 2025, the examination is in the preliminary stages.

Based upon available information, the Company does not believe that the audit will result in any adjustment that would result in a material change in the Company’s financial position.

To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by tax authorities to the extent utilized in a future period.

No additional provision has been made for withholding taxes related to undistributed foreign earnings of the Company’s wholly owned foreign subsidiaries or for unrecognized deferred tax liabilities for temporary differences related to investments in foreign subsidiaries.

The Company has determined that unremitted foreign earnings are not considered indefinitely reinvested to the extent foreign earnings can be distributed without a significant tax cost.

As such, the Company has estimated that no additional tax liability will arise as a result of the distribution of such earnings.

The following table summarizes income taxes paid net of tax refunds:

United States federal

United States state and local

Total income taxes paid net of tax refunds

Net Income (Loss) per Share

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As the liquidation and dividend rights are identical, losses are allocated on a proportionate basis and the resulting net income (loss) 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.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Basic and diluted Net income (loss) attributable to ordinary shareholders was calculated as follows:

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Options to purchase ordinary shares

Performance options to purchase ordinary shares

Unvested RSUs

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The Company’s unvested RSUs and PSUs have been excluded from the computation of basic net income (loss) per share attributable to ordinary shareholders.

Diluted earnings per share includes the assumed exercise of dilutive options and the assumed issuance of unvested RSUs and performance-based awards for which the performance condition has been met as of the date of determination, using the treasury stock method unless the effect is anti-dilutive.

Diluted earnings per share includes the assumed exercise of dilutive options and the assumed issuance of unvested RSUs and PSUs for which the market or performance condition has been met as of the date of determination,

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

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 stock options and the average unrecognized compensation expense for unvested share-based compensation awards, would be used to purchase the Company’s ordinary stock at the average market price during the period.

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Share options to purchase ordinary shares

Performance share options to purchase ordinary shares

Unvested RSUs

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Total anti-dilutive shares

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.

Commitments and Contingencies

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The Company has entered into license agreements with various parties under which it is obligated to make contingent and non-contingent payments (see Note 13).

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Manufacturing Commitments

The Company entered into supply agreements with Regeneron to provide both clinical supply and commercial product (see Note 13).

In May 2023, the Company signed a letter of intent with a CDMO related to its technology transfer of the manufacturing process for ARCALYST drug substance.

In May 2023, the Company signed a letter of intent with Samsung related to its technology transfer of the manufacturing process for ARCALYST drug substance.

The Company has additionally entered into agreements with several CDMOs to provide the Company with preclinical and clinical trial materials for its non-ARCALYST assets.

As of December 31, 2025, the Company had committed to minimum payments under these agreements totaling $ 175,704 , of which $ 46,924 are due within one year.

The Company issued termination notices to CDMOs in February 2025 to terminate the clinical supply agreements for the production of abiprubart.

During the year ended December 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

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

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 December 31, 2025, the Company estimates the future cash payments under such Performance Cash Awards to be $ 23,118 if the milestones are achieved.

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 December 31, 2025, and no expense has been recognized related to such awards.

Indemnification Agreements

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

Segment Information

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.

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Total operating expenses

Other income (1)

Other income, net (1)

Income (loss) before income taxes

1 unchanged sentence

Net income (loss)

Other significant noncash items:

Other significant non-cash items:

Share-based compensation expense

2 unchanged sentences

(1) Includes interest income of $ 11,636 , $ 9,036 and $ 8,227 for the years ended December 31, 2025, 2024 and 2023 respectively.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

The following table presents total revenue by geographic region of the customer for years ended December 31, 2025, 2024 and 2023:

United States

United Kingdom

Rest of world

Total revenue

The following table presents property and equipment, net by geographic region:

Property and Equipment, net

United States

United Kingdom

Rest of world

Total property and equipment, net

Benefit Plans

The Company has established a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code.

This plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis.

This plan covers substantially all Kiniksa US employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis.

The Company provides matching contributions of 100 % of the first 3 % of each participant’s salary contributed, plus 50 % for each of the next 2 % contributed.

1 unchanged sentence

During the years ended December 31, 2025, 2024 and 2023, the Company contributed $ 3,544 , $ 2,923 and $ 2,305 respectively, to the plan.

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Amounts in thousands, except share and per share amounts)

Subsequent Events

The Company issued termination notices to CDMOs in February 2025 to terminate the clinical supply agreements for the production of abiprubart.

The terminations will be effective in March 2025, and the Company is currently performing its analysis of the financial impact of the terminations.

As of the date of this report, the Company expects to record between $ 14,000 and $ 17,000 in research and development expense because of these terminations during the year ended December 31, 2025.

These estimated costs are subject to ongoing negotiations, the terms and conditions of the agreements and actual cost may differ.

The Company will record these amounts as research and development expenses.

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures