ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and related notes included elsewhere in this Annual Report. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the risks identified in Part I-Item 1A “Risk Factors” section of this Annual Report and our other filings with the SEC, our actual results could differ materially from the results, performance or achievements expressed in or implied by these forward-looking statements.

Overview

We are a biopharmaceutical company developing and commercializing novel therapies for diseases with unmet need, with a focus on cardiovascular indications. Our portfolio of assets is based on strong biologic rationale or validated mechanisms and offers the potential for differentiation.

ARCALYST is an IL-1α and IL-1β cytokine trap. In 2017, we licensed ARCALYST from Regeneron, which discovered and initially developed the drug. Our exclusive license to ARCALYST from Regeneron includes worldwide rights, excluding the Middle East and North Africa, for all applications other than those in oncology and local administration to the eye or ear. We received FDA approval of ARCALYST for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older in March 2021. Recurrent pericarditis is a painful inflammatory cardiovascular disease with an estimated United States prevalent population of approximately 40,000 patients seeking and receiving medical treatment. ARCALYST is also approved in the United States for the treatment of CAPS, including FCAS and Muckle-Wells Syndrome in adults and children 12 years and older, and the maintenance of remission in DIRA in adults and children weighing 10 kg or more. ARCALYST is commercially available across the United States through a select network of specialty pharmacies. We are responsible for sales and distribution of ARCALYST in all approved indications in the United States, and evenly split profits on sales as well as third party proceeds with Regeneron. In 2022, we granted Huadong exclusive rights to develop and commercialize ARCALYST in the Huadong Territory. In 2023, Regeneron initiated a technology transfer of the manufacturing process for ARCALYST drug substance, and we are working to qualify Samsung as our replacement CDMO.

KPL-387 is an investigational, fully human immunoglobulin G2 monoclonal antibody that binds IL1-R1, inhibiting IL-1α and IL-1β mediated signaling. KPL-387 is an independently developed asset that we believe has the potential to further advance recurrent pericarditis treatment options for patients by providing the added convenience of monthly subcutaneous dosing with a liquid formulation. In June 2024, we initiated a Phase 1 clinical trial of KPL-387 in normal healthy volunteers. In February 2025, we announced our plan to initiate a Phase 2/3 clinical trial of KPL-387 in recurrent pericarditis in mid-2025. We expect data from the Phase 2 portion of the trial in the second half of 2026.

KPL-1161 is an independently developed, pre-clinical, Fc-modified immunoglobulin G2 monoclonal antibody that binds IL-1R1, inhibiting IL-1α- and IL-1β-mediated signaling. KPL-1161 is a modified version of KPL-387 designed to have an increased drug half-life that we believe could support quarterly subcutaneous dosing.

Abiprubart is an investigational monoclonal antibody inhibitor of CD40-CD154 costimulatory interaction, which we believe to be an attractive approach to address multiple autoimmune disease pathologies. We hold an exclusive worldwide license to abiprubart from BIDMC. We previously announced a Phase 2b clinical trial of abiprubart in Sjögren’s Disease. In February 2025, we announced our plans to discontinue development of abiprubart in the indication and explore strategic alternatives for the asset.

Mavrilimumab is an investigational monoclonal antibody inhibitor targeting GM-CSFRα. In 2017, we licensed exclusive worldwide rights in all indications to mavrilimumab from MedImmune. In February 2025, we announced our termination of our license agreement from MedImmune for convenience, effective in May 2025. In addition, in February 2025, we 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 60 days of the notice, the mavrilimumab Huadong Collaboration Agreement will terminate in April 2025.

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Our ability to generate product revenue sufficient to sustain our organization will depend heavily on a number of factors, including the continued commercialization of ARCALYST, the development and eventual commercialization of one or more of our current or future product candidates, if approved, and the management of our costs consistent with our current operating plan. For the twelve months ended December 31, 2024, our net loss was $43.2 million, as compared to net income of $14.1 million for the year ended December 31, 2023. As of December 31, 2024, we had an accumulated deficit of $521.1 million compared to an accumulated deficit of $478.0 million as of December 31, 2023.

As of December 31, 2024, we had cash, cash equivalents and short-term investments of $243.6 million. We believe that our existing cash, cash equivalents and short-term investments will enable us to fund our operating expenses and capital expenditure requirements for at least the next 12 months from the date of issuance of the audited consolidated financial statements included in this Annual Report. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect. See “Management’s Discussion and Analysis of Financial Condition and Results Of Operations — Liquidity and Capital Resources.”

Components of Our Results of Operations

Product revenue, net

We have been generating product revenue from sales of ARCALYST since April 2021. ARCALYST is sold through a third party logistics provider that distributes primarily through a select network of specialty pharmacies (collectively, “customers”), which deliver the medication to patients by mail.

Net revenue from product sales is recognized at the transaction price when the customer obtains control of our product, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider.

Our 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. These adjustments represent variable consideration under ASC 606 and are estimated using the expected value method and are recorded when revenue is recognized on the sale of the product. These adjustments are established by management as its best estimate based on available information and will be adjusted to reflect known changes in the factors that impact such allowances. Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products.

License and collaboration revenue

License and collaboration revenue includes amounts recognized related to upfront payments, royalty revenue, milestone payments and products sold under collaboration agreements.

In February 2022, we entered into the Huadong Collaboration Agreements, pursuant to which we granted Huadong exclusive rights to develop and commercialize the Huadong Licensed Products in the Huadong Territory. In February 2025, we 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 60 days of the notice, the mavrilimumab Huadong Collaboration Agreement will terminate on April 25, 2025. We otherwise retain our current rights to the Huadong Licensed Products outside the Huadong Territory. For more information, see “Business –License and Acquisition Agreements—Out-Licensing Agreements—Huadong Collaboration Agreements”.

Under the Huadong Collaboration Agreements, we received a total upfront cash payment of $22.0 million, which includes $12.0 million for the Huadong Territory license of ARCALYST and $10.0 million for the Huadong Territory license of mavrilimumab. In the fourth quarter of 2024, following the achievement of a regulatory milestone under the ARCALYST Huadong Collaboration Agreement, Huadong became obligated to make an additional cash payment of $20.0 million, which was received in the first quarter of 2025. In addition, we will be eligible to receive additional contingent sales-based milestones payments related to ARCALYST. Huadong will also be obligated to pay us tiered percentage royalties on ARCALYST ranging from the low-to-mid teens on annual net sales in the Huadong

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Territory, subject to certain reductions tied to ARCALYST manufacturing costs and certain other customary reductions, with an aggregate minimum floor. Royalties will be payable on a country-by-country or region-by-region basis until the later of (i) 12 years after the first commercial sale of ARCALYST in such country or region in the Huadong Territory, (ii) the date of expiration of the last valid patent claim of our patent rights or any joint collaboration patent rights that covers ARCALYST in such country or region in the Huadong Territory, and (iii) the expiration of the last regulatory exclusivity for ARCALYST in such country or region in the Huadong Territory. We recognized the $10.0 million related to the mavrilimumab license during the year ended December 31, 2022 and do not expect to recognize any additional license and collaboration revenue following the termination of the mavrilimumab Huadong Collaboration Agreement. We have recognized $0.2 million of revenue of the $32.0 million transaction price under the ARCALYST license agreement as of December 31, 2024, and will recognize the remaining revenue as materials are shipped.

In August 2022, we entered into the Genentech License Agreement, pursuant to which we granted Genentech exclusive worldwide rights to develop and commercialize the Genentech Licensed Products. For more information, see “Business –License and Acquisition Agreements—Out-Licensing Agreements—Genentech License Agreement”.

Under the Genentech License Agreement, we received an upfront payment of $80.0 million for the license. Additionally, in 2023, we received a total of $35.0 million in additional payments from Genentech related to delivery of certain drug material to Genentech and Genentech’s achievement of a development milestone. 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 $10.0 million, which was received in the first quarter of 2024. In the second quarter of 2024, we received $5.0 million following the achievement of a development milestone related to a third indication under the Genentech License Agreement. We will be eligible to receive up to a total of approximately $600.0 million in contingent payments, including specified development, regulatory and sales-based milestones, of which approximately $570.0 million remains as of December 31, 2024. We will also be eligible to receive tiered percentage royalties on a Genentech Licensed Product-by-Genentech Licensed Product basis ranging from low-double digits to mid-teens on annual net sales of each Genentech Licensed Product, subject to certain customary reductions, with an aggregate minimum floor, before fulfilling our upstream financial obligations. Royalties will be payable on a Genentech Licensed Product-by-Genentech Licensed Product and country-by-country basis until the latest to occur of the expiration of certain patents that cover a Genentech Licensed Product, the expiration of regulatory exclusivity for such Genentech Licensed Product, or the tenth anniversary of first commercial sale of such Genentech Licensed Product in such country. As of December 31, 2024, we have recognized the $130.0 million received from Genentech under the Genentech License Agreement as revenue.

Operating Expenses

Cost of Goods Sold

Cost of goods sold includes production and distribution costs of ARCALYST, amortization of the $20.0 million payment we made to Regeneron in the first quarter of 2021 upon achievement of a regulatory milestone and other miscellaneous product costs associated with ARCALYST. Cost of goods sold also includes labor and overhead costs associated with the production of ARCALYST associated with supply chain, quality, and regulatory activities, and the technology transfer of the manufacturing process for the ARCALYST drug substance.

Collaboration expenses

Collaboration expenses consist of Regeneron’s share of the profit related to ARCALYST sales under the Regeneron Agreement and the cost of products sold under collaboration agreements. We evenly split profits on sales of ARCALYST with Regeneron, where profits are determined after deducting from net sales of ARCALYST certain costs related to the manufacturing and commercialization of ARCALYST. Such costs include but are not limited to (i) our cost of goods sold for product used, sold or otherwise distributed for patient use by us; (ii) customary commercialization expenses, including the cost of our field force, and (iii) our cost to market, advertise and otherwise promote ARCALYST, with such costs identified in subsection (iii) subject to specified limits. With respect to the technology transfer of ARCALYST drug substance manufacturing initiated by Regeneron in March 2023, to the extent permitted by the Regeneron Agreement, the fully-burdened costs of each of us and Regeneron incurred in performing such technology

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transfer shall also be deducted from net sales of ARCALYST to determine profit. We also evenly split with Regeneron any proceeds received by us 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.

Research and Development Expenses

Research and development expenses consist primarily of costs incurred in connection with the research and development of our product candidates. We expense research and development costs as incurred. These expenses may include:

●expenses incurred to conduct the necessary preclinical studies and clinical trials required to obtain regulatory approval;

●expenses incurred under agreements with CROs that are primarily engaged in the oversight and conduct of our clinical trials and CDMOs that are primarily engaged to provide preclinical and clinical drug substance and product for our research and development programs for our product candidates;

●other costs related to acquiring and manufacturing preclinical and clinical trial materials, including manufacturing validation batches, as well as investigative sites and consultants that conduct our clinical trials, preclinical studies and other scientific development services;

●payments made in cash or equity securities under third party licensing, acquisition and other similar agreements;

●employee-related expenses, including salaries and benefits, travel and share-based compensation expense for employees engaged in research and development functions;

●costs related to compliance with regulatory requirements; and

●allocated facilities-related costs, which include rent and utilities, depreciation and other expenses.

We recognize external development costs based on an evaluation of the progress to completion of specific tasks using information provided to us by our service providers. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. 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.

Our direct research and development expenses are tracked on a program-by-program basis for our product candidates and consist primarily of external costs, such as fees paid to outside consultants, CROs, CDMOs and research laboratories in connection with our preclinical development, process development, manufacturing and clinical development activities. Our direct research and development expenses by program also include fees incurred under license, acquisition and other similar agreements. We do not allocate employee costs or facility expenses, including depreciation or other indirect costs, to specific programs because these costs are deployed across multiple programs and, as such, are not separately classified. We use internal resources primarily to conduct our research and discovery activities as well as for managing our preclinical and clinical development, process development and manufacturing clinical and preclinical materials.

Research and development activities are central to our business. Product candidates in later stages of clinical development generally have higher costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. As a result, we expect that our research and development

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expenses will be substantial over the next several years as we conduct our ongoing and/or planned clinical trials for our product candidates, as well as conduct other preclinical and clinical development, and make regulatory filings for our product candidates.

At this time, we cannot reasonably estimate or know the nature, timing and costs of the efforts that will be necessary to complete the clinical development of our current or future product candidates or when, if ever, we will realize revenue from the sale of our current or future product candidates. This uncertainty is due to the numerous risks and uncertainties, including those described in Part I, Item 1A. “Risk Factors” in this Annual Report.

Selling, General and Administrative Expenses

Selling, general and administrative expenses consist primarily of salaries and benefits, including share based compensation expense for personnel in selling, marketing, medical, executive, business development, finance, human resources, legal and support personnel functions. Selling, general and administrative expenses also include external commercialization, marketing, and professional fees for legal, patent, and accounting services.

We expect that our selling, general and administrative expenses will continue to increase in the future as we continue to expand our infrastructure related to the commercialization of ARCALYST and our other product candidates, if approved.

Other Income

Other income consists of interest income recognized from investments in money market funds, United States Treasury notes and other miscellaneous income offset by expenses related to investments.

Income Taxes

Prior to the Redomiciliation, our principal holding company was incorporated and principally subject to taxation in Bermuda. Following the Redomiciliation, our principal holding company is incorporated and principally subject to taxation in the United Kingdom. Under the current laws of Bermuda, there is no corporate income tax levied on an exempted company’s income, resulting in an effective zero percent tax rate. As a result, we have not recorded any income tax benefits from our losses incurred in Bermuda during each reporting periods in which it was incorporated there, and no net operating loss carryforwards are currently available to us for those losses. Following the Redomiciliation, our income is subject to the enacted United Kingdom statutory corporate tax rate and net operating losses incurred have an indefinite carryforward. Our wholly owned United States subsidiaries, Kiniksa US, and Primatope Therapeutics, Inc. are subject to federal and state income taxes in the United States. Our wholly owned subsidiary Kiniksa UK, its Swiss branch office, and Kiniksa UK’s wholly owned subsidiaries, Kiniksa Pharmaceuticals (Germany) GmbH, Kiniksa Pharmaceuticals (France) SARL, and Kiniksa Pharmaceuticals, GmbH (“Kiniksa Switzerland”) are subject to taxation in their respective countries.

In the first quarter of 2022, Kiniksa Bermuda transferred exclusive rights to develop and commercialize mavrilimumab in the Asia Pacific region, excluding Japan, to Kiniksa UK. In the third quarter of 2022, Kiniksa Bermuda transferred exclusive worldwide rights to develop and commercialize vixarelimab to Kiniksa UK. In the fourth quarter of 2023, all rights, title and interest in, among other things, certain contracts, intellectual property rights, product filings and approvals and other information, plans and inventory owned insofar as they related exclusively or primarily to ARCALYST were allocated by Kiniksa UK to its Swiss branch office. In the first quarter of 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, KPL-1161 and other preclinical assets, with such exceptions as necessary to allow the completion of Cohort 4 of our Phase 2 clinical trial of abiprubart in rheumatoid arthritis (“RA”). In connection with each of the foregoing transfers and /or allocations, we recognized a step-up in basis and did not incur any material tax liabilities.

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In the second quarter of 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 the fourth quarter of 2024, Kiniksa UK contributed all of its rights, title and interest in, among other things, certain contracts, 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. In connection with the termination of Kiniksa UK rights and the contribution, we revalued the assets at fair market value and did not incur any material tax liabilities.

Results of Operations

Comparison of the Years Ended December 31, 2024, 2023 and 2022

The following table summarizes our results of operations for the years ended December 31, 2024, 2023 and 2022:

Years Ended Comparison Comparison

December 31, Increase/(Decrease) Increase/(Decrease)

(in thousands) (in thousands, except percentages)

Revenue:

Operating expenses:

Product Revenue, Net

We recognized net revenue from the sale of ARCALYST of $417.0 million, $233.2 million and $122.5 million for the years ended December 31, 2024, 2023 and 2022, respectively. The increases in 2024 and 2023 were primarily driven by an increase in patient enrollment.

License and Collaboration Revenue

We reported $6.2 million of license and collaboration revenue for the year ended December 31, 2024, primarily driven by the achievement of a $5.0 million development milestone related to a third indication under the Genentech License Agreement, $0.7 million of products sold under the ARCALYST Huadong Collaboration Agreements, and $0.2 million of deferred revenue recognized related to the delivery of such materials. We reported $37.1 million of license

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and collaboration revenue for the year ended December 31, 2023, related to the Genentech License Agreement primarily driven by the achievement of $25.0 million in development milestones related to two new indications, materials delivered and our ongoing recognition of the transaction price related to the in-progress Phase 2b clinical trial of vixarelimab in prurigo nodularis. We reported $97.7 million of license and collaboration revenue for the year ended December 31, 2022, which primarily consisted of $87.7 million for revenue related to the Genentech License Agreement and $10.0 million in revenue recognized upon the signing of the mavrilimumab Huadong Collaboration Agreement in February of 2022. We expect to recognize $31.8 million of deferred revenue related to the ARCALYST Huadong Collaboration Agreement over the life of the agreement as materials are delivered.

Cost of Goods Sold

We recognized cost of goods sold of $60.9 million, $33.4 million, and $22.9 million for the years ended December 31, 2024, 2023 and 2022, respectively. The increase of $27.5 million in 2024 from 2023 related primarily to the increase in sales of ARCALYST and a $12.6 million increase related to the technology transfer of the manufacturing process offset by a decrease in average cost per unit resulting from favorable production variances. The increase of $10.5 million in 2023 from 2022 related primarily to the increase in sales of ARCALYST and $3.3 million related to the initiation of the technology transfer of the manufacturing process offset by a decrease in average cost per unit resulting from favorable production variances.

Collaboration Expenses

We recognized collaboration expenses of $128.3 million, $56.5 million and $24.1 million for the years ended December 31, 2024, 2023 and 2022, respectively. The increase of $71.8 million in 2024 from 2023 relates primarily to increased revenue from sales of ARCALYST driving higher profits under the Regeneron agreement and to a $10.0 million payment due to Regeneron related to a regulatory milestone achieved under the ARCALYST Huadong Collaboration Agreement. The increase of $32.5 million in 2023 from 2022 relates primarily to an increase in revenue from the sales of ARCALYST and improved profitability under the Regeneron agreement.

Research and Development Expenses

Years Ended Comparison Comparison

December 31, Increase/(Decrease) Increase/(Decrease)

(in thousands) (in thousands, except percentages)

Direct research and development expenses by program:

Research and development expenses were $111.6 million for the year ended December 31, 2024, compared to $76.1 million for the year ended December 31, 2023, or an increase of $35.5 million. Research and development expenses were $76.1 million for the year ended December 31, 2023 compared to $65.5 million for the year ended December 31, 2022, or an increase of $10.6 million.

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Direct costs for our KPL-387 program were $11.2 million, $2.5 million and less than $0.1 million for the years ended December 31, 2024, 2023 and 2022, respectively. During the year ended December 31, 2024, expenses primarily related to our Phase 1 study in normal healthy volunteers and manufacturing of clinical supply. During the year ended December 31, 2023, expenses primarily related to manufacturing of clinical supply.

Direct costs for our KPL-1161 program were $0.6 million for the year ended December 31, 2024. We did not incur any expenses related to KPL-1161 for the years ended December 31, 2023 and 2022. For the year ended December 31, 2024 expenses incurred primarily related to pre-clinical development.

Direct costs for our abiprubart program were $59.5 million, $28.4 million and $11.6 million for the years ended December 31, 2024, 2023 and 2022, respectively. During the year ended December 31, 2024 expenses incurred primarily related to a $18.5 million write-off of prepayments for future manufacturing we no longer expect to utilize, manufacturing of clinical material, continuation of cohort four and study wind-down activities of our Phase 2 clinical trial in RA and start-up costs of our Phase 2b clinical trial in Sjögren’s Disease. During the year ended December 31, 2023, expenses incurred primarily related to the manufacturing of clinical material, the continuation of the first two cohorts of the Phase 2 clinical trial of abiprubart in RA and Cohorts 3 and 4 of such trial. During the year ended December 31, 2022, expenses incurred primarily related to the first two cohorts of our Phase 2 clinical trial of abiprubart in RA, which was initiated in December 2021.

Direct costs of our mavrilimumab program were $0.6 million, $0.8 million and $6.4 million for the years ended December 31, 2024, 2023 and 2022, respectively. During the years ended December 31, 2024 and 2023, expenses related primarily to intellectual property maintenance. During the year ended December 31, 2022, expenses related primarily to the wind-down activities of the Phase 3 portion of our clinical trial of mavrilimumab in COVID-19 related ARDS.

Direct costs for our vixarelimab program were $1.5 million, $7.7 million and $12.8 million for the year ended December 31, 2024, 2023 and 2022, respectively. During the year ended December 31, 2024, expenses incurred were primarily related to the wind-down activities of our Phase 2b clinical trial in prurigo nodularis. During the years ended December 31, 2023 and 2022, expenses incurred related primarily to our ongoing Phase 2b clinical trial of vixarelimab in prurigo nodularis. The decrease of $5.1 million in 2023 from 2022 was primarily related to a decrease in active participants in our ongoing Phase 2b clinical trial of vixarelimab in prurigo nodularis.

Unallocated research and development expenses were $37.7 million, $34.1 million and $33.9 million for the years ended December 31, 2024, 2023 and 2022, respectively. The increase of $3.6 million in unallocated research and development expenses in 2024 from 2023 was primarily due to an increase in personnel to support our clinical trials. The increase of $0.2 million in unallocated research and development expenses in 2023 from 2022 was primarily due to timing of raw material purchases to support internal development. Personnel-related costs for the years ended December 31, 2024, 2023 and 2022 included share-based compensation of $6.1 million, $5.5 million and $6.8 million, respectively.

Selling, General and Administrative Expenses

Selling, general and administrative expenses were $168.0 million, $129.4 million and $98.0 million for the years ended December 31, 2024, 2023 and 2022, respectively. In 2022 and 2023, we expanded our ARCALYST salesforce to help drive further prescriber adoption and patient enrollments. The increase of $38.6 million in 2024 from 2023 was primarily due to an increase of $18.9 million in personnel-related costs and an increase in sales and marketing expenses of $13.5 million, largely attributable to a full year of expenses associated with the expansion of our salesforce in 2023 and an increase in professional fees of $2.8 million largely attributable to the Redomiciliation. The increase of $31.5 million in 2023 from 2022 was primarily due to an increase of $18.9 million in personnel-related costs and an increase in sales and marketing of $6.0 million largely attributable to the expansion of our salesforce. Personnel-related costs for the years ended December 31, 2024, 2023 and 2022 included share-based compensation of $22.9 million, $19.8 million and $17.7 million, respectively.

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Other Income

Other income was $9.5 million for the year ended December 31, 2024,compared to $8.5 million for the year ended December 31, 2023. The increase of $1.0 million was primarily due to interest earned on higher cash, cash equivalents and short-term investment balances. Other income was $8.5 million for the year ended December 31, 2023, compared to other income of $1.3 million for the year ended December 31, 2022. The increase was due primarily to higher interest rates on U.S. Treasury notes and a higher average balance in short term investments.

Benefit (Provision) for Income Taxes

For the year ended December 31, 2024, we recorded an income tax provision of $7.0 million relating primarily to income earned in Switzerland and the U.S., net of Foreign-Derived Intangible Income (“FDII”) deduction and U.S. federal and state R&D Credits utilized.

For the year ended December 31, 2023, we recorded an income tax benefit of $30.7 million relating to a non-cash deferred tax benefit of $33.8 million primarily associated with Kiniksa UK’s allocation of its ARCALYST assets to its Swiss branch office and the release of the valuation allowance on U.S. deferred tax assets offset by the establishment of a partial valuation allowance on our UK deferred tax assets. The net benefit in the net deferred tax asset was offset by current income tax expense of $3.1 million primarily associated with income earned in the UK and the United States.

For the year ended December 31, 2022, we recorded an income tax benefit of $172.3 million relating to a non-cash deferred tax benefit of $185.5 million primarily associated with the release of the valuation allowance on our UK deferred tax assets. Our UK deferred tax asset consists primarily of the tax basis of the intangible assets that were transferred to our wholly-owned UK subsidiary in 2021 and 2022.

Liquidity and Capital Resources

As of December 31, 2024, our principal source of liquidity was cash, cash equivalents and short-term investments, which totaled $243.6 million. Our net income (losses) were ($43.2) million, $14.1 million and $183.4 million for the years ended December 31, 2024, 2023 and 2022, respectively. We expect our cash balance and our expected cash inflows from operations to allow us to meet our current operating plan.

Under various agreements with third parties, we have agreed to make milestone payments, pay royalties, pay annual maintenance fees and to meet due diligence requirements, each based upon specified events. Pursuant to the Regeneron Agreement, we have entered into a supply agreement with Regeneron to purchase both clinical and commercial product. We have committed to minimum payments to Regeneron of $40.7 million, all of which are due within one year. We have entered into lease agreements for office and laboratory space, and vehicles, with total future lease payments of $11.3 million, $2.7 million of which are due within one year. In connection with our ongoing technology transfer of ARCALYST drug substance manufacturing, we have entered into a manufacturing commitment with Samsung to establish a new manufacturing site for ARCALYST drug substance. Such commitment, which includes the purchase of raw materials and related service fees, obligates us to minimum payments of $151.0 million, $15.2 million of which are due within one year. We have additionally entered into agreements with several CDMOs to provide us with preclinical and clinical trial materials for our non-ARCALYST assets, which obligate us to minimum payments of $40.8 million, $39.0 million of which are due within one year. In February 2025 we issued termination notices to several of these CDMOs to terminate clinical supply agreements for the production of abiprubart. The terminations will be effective in March 2025, and we are currently performing an analysis of the financial impact of the terminations. As of the date of this report, we expect to pay between $14.0 million and $17.0 million in termination cost.

Under various agreements with third parties, we are entitled to receive upfront payments, milestone payments, and royalties, each based upon specified milestones. During the year ended December 31, 2024 we received $10.0 million, following Genentech’s achievement of a development milestone in the fourth quarter of 2023 related to a second indication under the Genentech License Agreement and $5.0 million following Genentech’s achievement of a development milestone related to a third indication under the Genentech License Agreement. In the fourth quarter of

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2024, following Huadong’s achievement of a regulatory milestone under the ARCALYST Huadong Collaboration Agreement, Huadong became obligated to pay a $20.0 million milestone, which was received in the first quarter of 2025.

These agreements impact our short-term and long-term liquidity and capital needs. As of December 31, 2024, we had cash, cash equivalents and short-term investments of $243.6 million.

Cash Flows

The following table summarizes our cash flows for each of the periods presented:

Years Ended

December 31,

(in thousands)

Net cash provided by operating activities $ 25,689 $ 13,301 $ 5,807

Net cash provided by financing activities 12,266 1,495 2,516

Operating Activities

Net cash provided by operations was $25.7 million for the year ended December 31, 2024, compared to $13.3 million for the year ended December 31, 2023. The increase in cash provided by operating activities is primarily due to an increase in net contribution from higher ARCALYST sales, offset by a decrease in cash received from licensing agreements of $20.0 million.

Net cash provided by operations was $13.3 million for the year ended December 31, 2023, compared to $5.8 million for the year ended December 31, 2022. The increase in cash provided by operating activities is primarily due to an increase in net contribution from higher ARCALYST sales, offset by a decrease in cash received from licensing agreements of $67.0 million.

Investing Activities

Net cash provided by investing activities was $37.7 million for the year ended December 31, 2024, compared to net cash used in investing activities of $29.6 million for the year ended December 31, 2023 as part of managing our cash and short-term investment portfolio mix.

Net cash used in investing activities was $29.6 million for the year ended December 31, 2023, compared to $8.1 million for the year ended December 31, 2022 as part of managing our cash and short-term investment portfolio mix.

Financing Activities

During the years ended December 31, 2024, 2023 and 2022, net cash provided by financing activities was $12.3 million, $1.5 million and $2.5 million, respectively, consisting of proceeds from the exercise of employee share options and our 2018 Employee Share Purchase Plan (the “2018 ESPP”).

Funding Requirements

We expect to incur significant expenses in connection with our ongoing and planned activities as we continue to commercialize ARCALYST and advance our current and future product candidates through preclinical and clinical development, seek regulatory approval and commercialize one or more of our current or future product candidates, if approved. We may also incur expenses in connection with the in-licensing or acquisition of additional product candidates. As a result, we expect to incur additional expenses related to milestone, royalty and other payments payable

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to third parties with whom we have entered into license, acquisition and other similar agreements to acquire the rights to our product candidates. We expect to incur expenses as we:

●support our sales, marketing and distribution capabilities, infrastructure and organization to commercialize ARCALYST and any product candidates for which we may obtain marketing approval;

●conduct new and ongoing research and pre-clinical and clinical development of our product candidates, including our planned Phase 2/3 clinical trial of KPL-387 in recurrent pericarditis, our ongoing Phase 1 clinical trial of KPL-387 in normal healthy volunteers and our pre-clinical investigations of KPL-1161;

●manufacture our products and product candidates for clinical or commercial use, increase our manufacturing capabilities, add additional manufacturers or suppliers and perform activities related to our technology transfer of the process for manufacturing ARCALYST drug substance;

●seek regulatory and marketing approvals for our product candidates that successfully complete clinical trials, if any;

●identify, assess and study new or expanded indications for our products and product candidates and/or new or alternative dosing levels, dosing frequencies or administrations of our products and product candidates;

●make milestone or other payments under any current or future license, acquisition, collaboration or other strategic transaction agreement;

●seek to identify, assess and study new or expanded indications for our products or product candidates, new or alternative dosing levels and frequency for our products or product candidates, or new or alternative administration of our products or product candidates, including method, mode or delivery device;

●seek to identify, assess, acquire or develop additional product candidates;

●address litigation arising out of, but not limited to, product liability claims, intellectual property disputes, disputes arising from our collaboration and license agreements and employment-related disputes;

●enter into licensing, acquisition, collaboration or other strategic transaction agreements;

●seek to maintain, protect and expand our intellectual property portfolio;

●seek to attract and retain skilled personnel;

●create additional infrastructure to support our product development and commercialization efforts; and

●experience delays or encounter issues with any of the above, including but not limited to failed trials, complex results, safety issues, regulatory challenges that require longer follow-up of existing trials, additional major trials, additional supportive trials in order to pursue marketing approval, a pandemic or other outbreak of disease or disruptions to the national or global economy.

We believe that our existing cash, cash equivalents and short-term investments will enable us to fund our operating expenses and capital expenditure requirements for at least the next 12 months. The future viability of our company is dependent on our ability to fund our operations through sales of ARCALYST and/or raise additional capital, such as through debt or equity offerings, as needed. We anticipate that we may require additional capital if we choose to pursue in-licenses or acquisitions of other product candidates and technologies or their related businesses. We expect to continue to incur significant expenses related to product manufacturing, including technology transfer costs, sales, marketing and distribution of ARCALYST. In addition, if we obtain regulatory approval for any of our current or future product candidates, pursue additional indications or additional territories for our products or any of our current or future

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product candidates, we expect to incur significant expenses related to product development and manufacturing, sales, marketing and distribution, depending on where we choose to commercialize.

Because of the numerous risks and uncertainties associated with research, development and commercialization of biologic products, we are unable to estimate the exact amount of our working capital requirements. Our future funding requirements may be impacted by a number of factors, including those described in Part I, Item 1A. “Risk Factors” in this Annual Report.

Until such time, if ever, as we can generate substantial and sustained product revenue, we expect to finance our cash needs through a combination of public or private equity offerings, debt financings, or other sources, including, licensing, collaboration, marketing, distribution or other strategic transactions or arrangements with third parties. To the extent that we raise additional capital through the sale of equity or convertible debt securities, our shareholders’ ownership interest may be materially diluted, and the terms of such securities could include liquidation or other preferences that adversely affect our shareholders’ rights as an ordinary shareholder. Debt financing and preferred equity financing, if available, may involve agreements that include restrictive covenants that limit our ability to take specified actions, such as incurring additional debt, making capital expenditures or declaring dividends. In addition, debt financing would result in fixed payment obligations.

If we raise funds through licensing, collaboration, marketing, distribution or other strategic transactions or arrangements with third parties, we may have to relinquish valuable rights to our technologies, product candidates or future revenue streams, or otherwise agree to terms that may not be favorable to us. If we are unable to obtain funding, we could be forced to delay, reduce or eliminate some or all of our research and development programs for product candidates, product portfolio expansion or commercialization efforts, which could adversely affect our business prospects, or we may be unable to continue operations.

Critical Accounting Policies and Significant Judgments and Estimates

Our consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States. The preparation of our consolidated financial statements and related disclosures requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue, costs and expenses, and the disclosure of contingent assets and liabilities in our financial statements. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions or conditions.

While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements included elsewhere in this Annual Report, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements.

Revenue Recognition

ASC 606 outlines a five-step process for recognizing revenue from contracts with customers: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the separate performance obligations in the contract, and (v) recognize revenue associated with the performance obligations as they are satisfied.

We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. Once a contract is determined to be within the scope of ASC 606, we determine the performance obligations that are distinct. We recognize as revenues the amount of the transaction price that is allocated to each respective performance obligation when the performance obligation is satisfied or as it is satisfied. Generally, our performance obligations are transferred to customers at a point in time, typically upon receipt of the product by the customer.

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ASC 606 requires entities to record a contract asset when a performance obligation has been satisfied or partially satisfied, but the amount of consideration has not yet been received because the receipt of the consideration is conditioned on something other than the passage of time. ASC 606 also requires an entity to present a revenue contract as a contract liability in instances when a customer pays consideration, or an entity has a right to an amount of consideration that is unconditional (e.g. receivable), before the entity transfers a good or service to the customer.

Product Revenue, Net

Net revenue from product sales is recognized at the transaction price when the specialty pharmacy or specialty distributors obtains control of our products, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider.

Our 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. These adjustments represent variable consideration under ASC 606 and are estimated using the expected value method and are recorded when revenue is recognized on the sale of the product. These adjustments are established by us as our best estimate based on available information and will be adjusted to reflect known changes in the factors that impact such allowances. Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products.

As of December 31, 2024, a 10% change in our product revenue allowance and reserve would not result in a material change in our net revenue.

Accrued Research and Development Expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses. This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. The majority of our service providers invoice us in arrears for services performed, on a pre-determined schedule or when contractual milestones are met; however, some require advanced payments. We make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of these estimates with the service providers and make adjustments if necessary. Examples of estimated accrued research and development expenses include fees paid to:

We base our expenses related to preclinical studies and clinical trials on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple research institutions and CROs that conduct and manage preclinical studies and clinical trials on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense. Payments under some of these contracts depend on factors such as the successful enrollment of participants and the completion of clinical trial milestones. 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.

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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. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, we adjust the accrual or the amount of prepaid expenses accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period. To date, there have not been any material adjustments to our prior estimates of accrued research and development expenses.

As of December 31, 2024, we have accrued $11 million of estimated research and development expenses.

Income Taxes

We account for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in our tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the benefit (provision) for income taxes. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe, based upon the weighting of both positive and negative evidence available, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected, cumulative recent earnings and considering prudent and feasible tax planning strategies. Significant judgment is required in assessing both positive and negative evidence available and, to the extent that a reversal of any portion of our valuation allowance against our deferred tax assets is deemed appropriate, a tax benefit will be recorded in our income tax benefit (provision) in the period of such reversal.

We believe our estimates for the valuation allowances against certain deferred tax assets recognized in our financial statements are appropriate based upon our assessment of the factors mentioned above.

Recently Issued Accounting Pronouncements

A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our annual consolidated financial statements included elsewhere in this Annual Report.

ITEM 7A.QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

Interest Rate Risk

We are exposed to market risk related to changes in interest rates. As of December 31, 2024, our cash, cash equivalents and short-term investments consisted of money market funds and United States Treasury notes. Our primary exposure to market risk is interest income sensitivity, which is affected by changes in the general level of United States interest rates. Such interest rates have and in the future may be subject to significant volatility. However, because of the short-term nature of the instruments in our portfolio, an immediate 100 basis point change in market interest rates would not have a material impact on the fair market value of our investment portfolio or on our financial position or results of operations.

ITEM 8.FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

The financial statements required to be filed pursuant to this Item 8 are appended to this report. An index of those financial statements is found in Item 15.

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None.

ITEM 9A. CONTROLS AND PROCEDURES.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated, as of the end of the period covered by this Annual Report, the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act. Based on that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of December 31, 2024.

In designing and evaluating our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act), management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives.

Management’s Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over our financial reporting, as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act.

Our management conducted an assessment of the effectiveness of our internal control over financial reporting as of December 31, 2024 using the criteria set forth in “Internal Control – Integrated Framework (2013)” issued by the Committee of Sponsoring Organizations of the Treadway Commission.

Based on this assessment, our management concluded that, as of December 31, 2024, our internal control over financial reporting was effective.

The effectiveness of the Company’s internal control over financial reporting as of December 31, 2024 has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report which appears herein.

Changes in Internal Control over Financial Reporting

There was no change in our internal control over financial reporting, (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the fourth quarter of the year ended December 31, 2024 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

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ITEM 9B. OTHER INFORMATION.

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:

Trading Arrangement

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS.

Not applicable.

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PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE.

Except to the extent provided below, the information required to be disclosed by this Item will be set forth in our proxy statement for our 2025 Annual Meeting to be filed with the SEC within 120 days of December 31, 2024, and is incorporated into this Annual Report by reference.

We have adopted a written code of business conduct and ethics that applies to all of our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer and controller, or persons performing similar functions. Our code of business conduct and ethics is available in the “Investors” section of our website at www.kiniksa.comunder “Corporate Governance”. We intend to post on our website all disclosures that are required by law or the Nasdaq rules concerning any amendments to, or waivers from, any provision of the code. The reference to our website address does not constitute incorporation by reference of the information contained at or available through our website, and you should not consider it to be a part of this Annual Report.

ITEM 11. EXECUTIVE COMPENSATION.

The information required to be disclosed by this Item will be set forth in our proxy statement for our 2025 Annual Meeting to be filed with the SEC within 120 days of December 31, 2024, and is incorporated into this Annual Report by reference.

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES.

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PART IV

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

(a)(1) Financial Statements.

See the “Index to Consolidated Financial Statements” on page F-1 below for the list of financial statements filed as part of this report.

(a)(2) Financial Statement Schedules.

All schedules have been omitted because they are not required or because the required information is given in the Consolidated Financial Statements or Notes thereto set forth below beginning on page F-1.

(a)(3) Exhibits. See Exhibit Index.

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EXHIBIT INDEX

Incorporated by Reference

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10.40# Non-Employee Director Compensation Program *

101.INS Inline XBRL Instance Document ***

101.SCH Inline XBRL Taxonomy Extension Schema Document ***

101.LAB Inline XBRL Taxonomy Label Linkbase Document ***

* Filed herewith

** Furnished herewith

*** Submitted electronically herewith

# Indicates management contract or compensatory plan

+ Portions of the exhibit have been redacted in compliance with Regulation S-K Item 601(a)(6)

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ITEM 16. FORM 10-K SUMMARY

None.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

Date: February 25, 2025 By: /s/ Sanj K. Patel

Sanj K. Patel

Chief Executive Officer and Chairman of the Board of Directors

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.

Signature Title Date

Sanj K. Patel

Mark Ragosa

Michael R. Megna

/s/ Felix J. Baker Lead Independent Director February 25, 2025

Felix J. Baker

/s/ Stephen R. Biggar Director February 25, 2025

Stephen R. Biggar

/s/ M. Cantey Boyd Director February 25, 2025

M. Cantey Boyd

/s/ G. Bradley Cole Director February 25, 2025

G. Bradley Cole

/s/ Richard S. Levy Director February 25, 2025

Richard S. Levy

/s/ Thomas R. Malley Director February 25, 2025

Thomas R. Malley

/s/ Tracey L. McCain Director February 25, 2025

Tracey L. McCain

/s/ Kimberly J. Popovits Director February 25, 2025

Kimberly J. Popovits

/s/ Barry D. Quart Director February 25, 2025

Barry D. Quart

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INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Page

Report of Independent Registered Public Accounting Firm (PCAOB ID 238) F-2

Consolidated Balance Sheets F-5

Consolidated Statements of Operations and Comprehensive Income (Loss) F-6

Consolidated Statements of Shareholders’ Equity F-7

Consolidated Statements of Cash Flows F-8

Notes to Consolidated Financial Statements F-9

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Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of Kiniksa Pharmaceuticals International, plc

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of Kiniksa Pharmaceuticals International, plc and its subsidiaries (the "Company") as of December 31, 2024 and 2023, and the related consolidated statements of operations and comprehensive income (loss), of shareholders' equity and of cash flows for each of the three years in the period ended December 31, 2024, including the related notes (collectively referred to as the "consolidated financial statements"). We also have audited the Company's internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2024 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control - Integrated Framework (2013) issued by the COSO.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

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Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

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.

Accrued Research and Development Costs

As described in Notes 2 and 9 to the consolidated financial statements, the Company has entered into various research and development-related contracts with companies both inside and outside of the United States. 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. 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.

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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.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts

February 25, 2025

We have served as the Company’s auditor since 2016.

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KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)

December 31, December 31,

Assets

Current assets:

Prepaid expenses and other current assets 20,084 17,538

Property and equipment, net 662 734

Operating lease right-of-use assets 10,376 11,931

Other long-term assets 10,315 827

Liabilities and Shareholders’ Equity

Current liabilities:

Accrued collaboration expenses 48,157 16,939

Deferred revenue — 307

Operating lease liabilities 1,993 2,253

Other current liabilities 16,077 8,193

Non-current liabilities:

Non-current operating lease liabilities 7,862 10,005

Other long-term liabilities 1,823 1,858

Commitments and contingencies (Note 16)

Shareholders’ equity:

Accumulated other comprehensive income (loss) (163) 6

Total liabilities and shareholders’ equity $ 580,553 $ 526,322

The accompanying notes are an integral part of these consolidated financial statements.

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KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS)

(In thousands, except share and per share amounts)

Years Ended

December 31,

Revenue:

Operating expenses:

Comprehensive income (loss):

Other comprehensive income (loss):

Total other comprehensive income (loss) (169) (38) 110

The accompanying notes are an integral part of these consolidated financial statements.

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KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY

(In thousands, except share amounts)

Ordinary Shares Additional Accumulated Total

Shares Amount Capital Income (Loss) Deficit Equity

Share-based compensation expense — — 25,120 — — 25,120

Share-based compensation expense — — 27,149 — — 27,149

Net income — — — — 14,084 14,084

Share-based compensation expense — — 30,693 — — 30,693

Net loss — — — — (43,193) (43,193)

The accompanying notes are an integral part of these consolidated financial statements.

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KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

Years Ended

December 31,

Cash flows from operating activities:

Depreciation and amortization expense 1,695 2,341 2,402

Gain on disposal of property and equipment (25) — —

Loss on disposal of property and equipment 1 179 33

Changes in operating assets and liabilities:

Prepaid expenses and other current assets (2,710) (7,067) (3,858)

Contract asset — 7,656 (7,656)

Operating lease liabilities (3,984) (3,261) (3,007)

Other long-term liabilities (35) 19 1,569

Cash flows from investing activities:

Proceeds from sale of property and equipment 25 — 91

Purchases of property and equipment (277) (130) (105)

Cash flows from financing activities:

Net cash provided by financing activities 12,266 1,495 2,516

Net increase (decrease) in cash and cash equivalents 75,627 (14,761) 245

Supplemental information:

The accompanying notes are an integral part of these consolidated financial statements.

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KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

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

1. Nature of the Business and Basis of Presentation

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

The Company is the successor issuer to Kiniksa Pharmaceuticals, Ltd. (“Kiniksa Bermuda”). On June 27, 2024, the Company and Kiniksa Bermuda completed a transaction pursuant to a Bermuda court-approved scheme of arrangement (the “Scheme”), which had been previously approved by Kiniksa Bermuda’s shareholders. Pursuant to the Scheme, the shareholders of Kiniksa Bermuda became the shareholders of the Company and the Company became the ultimate parent and holding company of the Kiniksa organization, thereby effecting a change of incorporation from Bermuda to the United Kingdom (the “Redomiciliation”). As used herein, and unless the context otherwise requires, references to the “Company” prior to the Redomiciliation shall refer to Kiniksa Bermuda and from and after the Redomiciliation, to Kiniksa International. 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.

Principles of Consolidation

The Redomiciliation was accounted for as a change in the reporting entity between entities under common control and the historical basis of accounting was retained as if the entities had always been combined for financial reporting purposes. The consolidated financial statements for periods prior to the Redomiciliation are the consolidated statements of Kiniksa Bermuda as the predecessor to the Company for accounting and reporting purposes and, upon completion of the Redomiciliation, such historical consolidated financial statements became Kiniksa International’s historical consolidated financial statements.

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

Reclassifications

Certain prior year amounts have been reclassified for consistency with the current year presentation. 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.

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Table of Contents

KINIKSA PHARMACEUTICALS, LTD.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

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

Use of Estimates

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. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.

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.

Transactions in other currencies are recorded in the functional currency at the rate of exchange prevailing when the transactions occur. Monetary assets and liabilities denominated in other currencies are re-measured into the functional currency at the rate of exchange in effect at the balance sheet date. Exchange rate gains and losses arising from re-measurement of foreign currency-denominated monetary assets and liabilities are included in income or losses in the period in which they occur.

For the Company’s foreign subsidiaries where the local currency is the functional currency, assets and liabilities denominated in local currencies are translated into USD at end-of-period exchange rates and the resulting translation adjustments are reported as a component of accumulated other comprehensive income (loss) within shareholders’ equity.

Liquidity

The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. As of December 31, 2024, the Company had an accumulated deficit of $521,143. 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. As of December 31, 2024, the Company had cash, cash equivalents and short-term investments of $243,627.

KNSA US Equity

KNSA · 10-K · period ended 2024-12-31

ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

ITEM 7A.QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

ITEM 8.FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

ITEM 9A. CONTROLS AND PROCEDURES.

ITEM 9B. OTHER INFORMATION.

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS.

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE.

ITEM 11. EXECUTIVE COMPENSATION.

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES.

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

ITEM 16. FORM 10-K SUMMARY

KNSA US Equity☆

KNSA · 10-K · period ended 2024-12-31

ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

ITEM 7A.QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

ITEM 8.FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

ITEM 9A. CONTROLS AND PROCEDURES.

ITEM 9B. OTHER INFORMATION.

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS.

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE.

ITEM 11. EXECUTIVE COMPENSATION.

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES.

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

ITEM 16. FORM 10-K SUMMARY

KNSA US Equity