Kiniksa Pharmaceuticals International, plc

Previous wording

KPL-387 is an investigational, fully human immunoglobulin G2 monoclonal antibody that binds human interleukin-1 receptor 1 (“IL-1R1”), 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.

Current wording

KPL-387 is an investigational, fully human immunoglobulin G2 monoclonal antibody that binds human interleukin-1 receptor 1 (“IL-1R1”), 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 July 2025, we announced that the Phase 2 dose-focusing portion of the pivotal Phase 2/3 clinical trial of KPL-387 in recurrent pericarditis had begun recruiting. We expect data from the Phase 2 portion of the trial in the second half of 2026.

Previous wording

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 three months ended March 31, 2025, our net income was $8.5 million. As of March 31, 2025, we had an accumulated deficit of $512.6 million.

Current wording

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 six months ended June 30, 2025, our net income was $26.4 million. As of June 30, 2025, we had an accumulated deficit of $494.8 million.

Previous wording

As of March 31, 2025, we had cash, cash equivalents and short-term investments of $268.3 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 theunaudited consolidated financial statements included in this Quarterly 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 “—Liquidity and Capital Resources.”

Current wording

As of June 30, 2025, we had cash, cash equivalents and short-term investments of $307.8 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 theunaudited consolidated financial statements included in this Quarterly 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 “—Liquidity and Capital Resources.”

Previous wording

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.

Current wording

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. ARCALYST is currently approved for sale only in the United States, and, therefore, we expect to derive substantially all of our product revenue from the United States for the foreseeable future.

Previous wording

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

Current wording

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.

Previous wording

net operating loss carryforwards are currently available to us for those losses. Following the Redomiciliation, our income is subject to the enacted UK statutory corporate tax rate and net operating losses incurred have an indefinite carryforward. Our wholly owned United States subsidiaries, Kiniksa Pharmaceuticals, Inc. (“Kiniksa US”), and Primatope Therapeutics, Inc. are subject to federal and state income taxes in the United States. Our wholly owned subsidiary Kiniksa Pharmaceuticals (UK), Ltd. (“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.

Current wording

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 UK. Under the 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 the reporting periods in which we were 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 UK statutory corporate tax rate and net operating losses incurred have an indefinite carryforward. Our wholly owned United States subsidiaries, Kiniksa Pharmaceuticals, Inc. (“Kiniksa US”), and Primatope Therapeutics, Inc. are subject to federal and state income taxes in the United States. Our wholly owned subsidiary Kiniksa Pharmaceuticals (UK), Ltd. (“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.

Previous wording

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.

Current wording

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. Kiniksa Switzerland held worldwide rights to develop and commercialize mavrilimumab until the cancellation of the license agreement from MedImmune, effective in May 2025. 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.

Previous wording

We recognized net revenue from the sale of ARCALYST of $137.8 million for the three months ended March 31, 2025, compared to $78.9 million for the three months ended March 31, 2024, an increase of $58.9 million. The increase in product revenue was primarily driven by an increase in patient enrollment.

Current wording

We recognized net revenue from the sale of ARCALYST of $156.8 million for the three months ended June 30, 2025, compared to $103.4 million for the three months ended June 30, 2024, an increase of $53.4 million. The increase in product revenue was primarily driven by an increase in patient enrollment.

Previous wording

We recognized cost of goods sold of $17.9 million for the three months ended March 31, 2025, compared to $10.6 million for the three months ended March 31, 2024, an increase of $7.3 million. The increase in cost of goods sold relates primarily to the increase in sales of ARCALYST. Cost of goods sold related to the technology transfer of the manufacturing process were consistent at $2.2 million for the three months ended March 31, 2025, and 2024.

Current wording

We recognized cost of goods sold of $18.6 million for the three months ended June 30, 2025, compared to $12.3 million for the three months ended June 30, 2024, an increase of $6.3 million. The increase in cost of goods sold relates primarily to the increase in sales of ARCALYST and unfavorable production variances. Cost of goods sold related to the technology transfer of the manufacturing process were $1.7 million for the three months ended June 30, 2025, compared to $2.8 million for the three months ended June 30, 2024, a decrease of $1.1 million.

Previous wording

Collaboration expenses were $43.8 million for the three months ended March 31, 2025, compared to $20.8 million for the three months ended March 31, 2024, an increase of $23.0 million. Collaboration expenses increased due to increased revenue from sales of ARCALYST.

Current wording

Collaboration expenses were $52.4 million for the three months ended June 30, 2025, compared to $30.0 million for the three months ended June 30, 2024, an increase of $22.4 million. Collaboration expenses increased due to increased revenue from sales of ARCALYST.

Previous wording

Direct costs for our KPL-387 program were $5.2 million during the three months ended March 31, 2025, compared to $1.1 million during the three months ended March 31, 2024. The increase in expenses incurred primarily related to our Phase 1 clinical trial in normal healthy volunteers during the three months ended March 31, 2025, as compared to the manufacturing of clinical supply during the three months ended March 31, 2024.

Current wording

Direct costs for our KPL-387 program were $8.5 million during the three months ended June 30, 2025, compared to $1.6 million during the three months ended June 30, 2024. The increase in expenses incurred primarily related to our Phase 1 clinical trial in normal healthy volunteers and the start-up of our Phase 2/3 clinical trial of KPL-387 in recurrent pericarditis during the three months ended June 30, 2025, as compared to the manufacturing of clinical supply during the three months ended June 30, 2024.

Previous wording

Direct costs for our KPL-1161 program were $0.1 million for the three months ended March 31, 2025. We did not incur any expenses related to KPL- 1161 for three months ended March 31, 2024. For the three months ended March 31, 2025 expenses incurred primarily related to pre-clinical development.

Current wording

Direct costs for our KPL-1161 program were $0.4 million for the three months ended June 30, 2025, compared to $0.1 million during the three months ended June 30, 2024. For the three months ended June 30, 2025 and 2024, expenses incurred primarily related to pre-clinical development.

Previous wording

The direct costs for our abiprubart program were $4.4 million during the three months ended March 31, 2025, compared to $15.1 million during the three months ended March 31, 2024, a decrease of $10.7 million. The decrease in expenses incurred primarily related to the close-out of our Phase 2b clinical trial in Sjögren’s Disease during the three months ended March 31, 2025 and $2.5 million of termination expenses associated with cancelled manufacturing agreements, as compared to the manufacturing of clinical material, continuation of cohort four of our Phase 2 clinical

Current wording

The direct costs for our abiprubart program were $0.6 million during the three months ended June 30, 2025, compared to $12.4 million during the three months ended June 30, 2024, a decrease of $11.7 million. The decrease in expenses incurred primarily related to the close-out of our Phase 2b clinical trial in Sjögren’s Disease during the three months ended June 30, 2025, as compared to the manufacturing of clinical material, continuation of cohort four of our Phase 2 clinical trial in rheumatoid arthritis (“RA”) and start-up costs of our Phase 2b clinical trial in Sjögren’s Disease during the three months ended June 30, 2024.

Previous wording

Unallocated research and development expenses were $9.2 million and $9.1 million for the three months ended March 31, 2025 and March 31, 2024, respectively. Personnel-related costs for the three months ended March 31, 2025 and 2024 included share-based compensation of $1.2 million and $1.5 million, respectively.

Current wording

Unallocated research and development expenses were $9.1 million and $8.9 million for the three months ended June 30, 2025 and June 30, 2024, respectively. Personnel-related costs for the three months ended June 30, 2025 and 2024 included share-based compensation of $1.7 million and $1.5 million, respectively.

Previous wording

Selling, general and administrative expenses were $43.5 million for the three months ended March 31, 2025, compared to $38.7 million for the three months ended March 31, 2024. The increase of $4.8 million was primarily due to an increase in sales and marketing costs of $2.6 million largely attributable to promotional activities and an increase of $2.4 million in personnel-related costs largely attributable to an increase in headcount. Personnel-related costs for the three months ended March 31, 2025 and 2024 included share-based compensation of $5.8 million and $5.4 million, respectively.

Current wording

Selling, general and administrative expenses were $46.9 million for the three months ended June 30, 2025, compared to $42.4 million for the three months ended June 30, 2024. The increase of $4.5 million was primarily due to an increase of $4.4 million in personnel-related costs largely attributable to an increase in headcount. Personnel-related costs for the three months ended June 30, 2025 and 2024 included share-based compensation of $6.6 million and $5.5 million, respectively.

Previous wording

We reported no license and collaboration revenue for the three months ended March 31, 2025. We reported $1.0 million of license and collaboration revenue for the three months ended March 31, 2024, related primarily to $0.7 million of products sold under the ARCALYST Huadong Collaboration Agreement, $0.2 million of deferred revenue recognized related to the delivery of such materials.* *

Current wording

We reported no license and collaboration revenue for the six months ended June 30, 2025. We reported $6.2 million of license and collaboration revenue for the six months ended June 30, 2024, primarily driven by the achievement of a $5.0 million development milestone related to a third indication under the Genentech License Agreement and $0.7 million of products sold under the ARCALYST Huadong Collaboration Agreements

Previous wording

For the three months ended March 31, 2025, we recorded an income tax provision of $7.0 million relating primarily to income earned in the UK, Switzerland and the United States, net of the Foreign Derived Intangible Income (“FDII”) deduction and United States federal and state research and development credits (“R&D Credits”). For the three months ended March 31, 2024, we recorded an income tax provision of $3.4 million relating primarily to income earned in the UK, Switzerland and the United States, net of the FDII deduction and R&D Credits.

Current wording

For the six months ended June 30, 2025, we recorded an income tax provision of $12.1 million relating primarily to income earned in the UK, Switzerland and the U.S., net of the FDII deduction, benefits related to share-based compensation and R&D Credits utilized. For the six months ended June 30, 2024, we recorded an income tax provision of $9.6 million relating primarily to income earned in the UK, Switzerland and the United States, net of the FDII deduction and R&D Credits.

Previous wording

As of March 31, 2025, our principal source of liquidity was cash, cash equivalents and short-term investments, which totaled $268.3 million. Net income (loss) was 8.5 million and ($17.7) million for the three months ended March 31, 2025 and 2024, respectively. We expect our cash balance and our expected cash inflows from operations to allow us to meet our current operating plan.

Current wording

As of June 30, 2025, our principal source of liquidity was cash, cash equivalents and short-term investments, which totaled $307.8 million. Net income (loss) was $26.4 million and ($21.6) million for the six months ended June 30, 2025 and 2024, respectively. We expect our cash balance and our expected cash inflows from operations to allow us to meet our current operating plan.

Previous wording

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 $35.4 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 $12.2 million, of which $3.9 million are due within one year. In connection with our ongoing technology transfer of ARCALYST drug substance manufacturing, we have entered into a Master Services Agreement and a Product Specific Agreement with Samsung. Our commitments under such agreements, which include the purchase of raw materials and related service fees, will obligate us to minimum payments of $151.1 million, $15.1 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 $6.6 million all of which are due within one year.

Current wording

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 $14.2 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 $11.9 million, of which $4.1 million are due within one year. In connection with our ongoing technology transfer of ARCALYST drug substance manufacturing, we have entered into a Master Services Agreement and a Product Specific Agreement with Samsung. Our commitments under such agreements, which include the purchase of raw materials and related service fees, will obligate us to minimum payments of $136.7 million, $0.7 million of which are due within one year. As of June 30, 2025, we have capitalized $18.4 million of production cost into inventory as semi-finished goods related to drug substance manufactured at Samsung. 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 $10.7 million all of which are due within one year. We have long-term incentive plans for our employees that may result in cash award payments of $22.3 million, based upon the achievement of certain regulatory milestones, none of which are expected to be achieved in the next year.

Previous wording

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

Current wording

Under various agreements with third parties, we are entitled to receive upfront payments, milestone payments, and royalties, each based upon specified milestones. In 2024, we received $15.0 million in development milestone payments from Genentech related to a second and third indication under the Genentech License Agreement. In 2025, we received a $20.0 million milestone payment related to Huadong’s achievement of a regulatory milestone under the ARCALYST Huadong Collaboration Agreement.

Previous wording

Net cash provided by operations was $22.3 million and $4.0 million for the three months ended March 31, 2025 and 2024, respectively. The increase in cash provided by operating activities is primarily due to an increase in cash received from licensing agreements of $10.0 million and an increase in net contribution from higher ARCALYST sales.

Current wording

Net cash provided by operations was $50.4 million and $9.2 million for the six months ended June 30, 2025 and 2024, respectively. The increase in cash provided by operating activities is primarily due to an increase in net contribution from higher ARCALYST sales and an increase in cash received from licensing agreements of $5.0 million.

Previous wording

Net cash used in investing activities was $51.5 million for the three months ended March 31, 2025, compared to net cash provided by investing activities of $25.5 million for the three months ended March 31, 2024. The increase in net cash used in investing activities was driven by managing our cash and short-term investment portfolio mix.

Current wording

Net cash used in investing activities was $55.4 million and $21.3 million for the six months ended June 30, 2025 and 2024, respectively. The increase in net cash used in investing activities was driven by managing our cash and short-term investment portfolio mix.

Previous wording

During the three months ended March 31, 2025 and 2024, net cash provided by financing activities was $2.8 million and $3.6 million, respectively, consisting of proceeds from the exercise of share options offset by payments in connection with ordinary shares tendered for employee tax obligations.

Current wording

During the six months ended June 30, 2025 and 2024, net cash provided by financing activities was $13.5 million and $3.4 million, respectively, consisting of proceeds from the exercise of share options offset by payments in connection with ordinary shares tendered for employee tax obligations.

Previous wording

●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;

Current wording

●conduct new and ongoing research and pre-clinical and clinical development of our product candidates, including our 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;