Exhibit 99.1

Kiniksa Pharmaceuticals Reports Second Quarter 2024 Financial Results and Recent Portfolio Execution

– ARCALYST® (rilonacept) Q2 2024 net product revenue of $103.4 million, representing 90% year-over-year growth –

– ARCALYST 2024 expected net product revenue increased to $405 - $415 million –

– Abiprubart clinical development fully funded; Phase 2b clinical trial in Sjögren’s Disease enrolling patients –

– Kiniksa expects to remain cash flow positive on an annual basis –

– Conference call and webcast scheduled for 8:30 am ET today –

LONDON– July 23, 2024 – Kiniksa Pharmaceuticals International, plc (Nasdaq: KNSA) (Kiniksa), a commercial-stage biopharmaceutical company with a pipeline of immune-modulating assets designed to target a spectrum of cardiovascular and autoimmune diseases, today reported second quarter 2024 financial results and recent portfolio execution.

“Kiniksa’s work to establish ARCALYST as the standard of care in recurrent pericarditis continues to drive the company’s commercial performance. As of the end of the second quarter, ~11% of the 14,000 multiple-recurrence target population were actively on ARCALYST treatment, and total average duration of therapy increased to approximately 26 months. We now expect 2024 ARCALYST net sales to increase to between $405 and $415 million from our previous guidance of between $370 and $390 million,” said Sanj K. Patel, Chairman and Chief Executive Officer of Kiniksa. “Within our pipeline, commencing enrollment in the abiprubart Phase 2b trial in Sjögren’s Disease, a debilitating, chronic autoimmune disease, which currently has no FDA-approved therapies, represents an exciting growth opportunity for the company. Clinical development of abiprubart in Sjögren’s Disease is fully funded in our current operating plan, and we expect to remain cash flow positive on an annual basis.”

Portfolio Execution

ARCALYST (IL-1α and IL-1β cytokine trap)

Abiprubart (anti-CD40 monoclonal antibody inhibitor of CD40-CD154 interaction)

Financial Results

Financial Guidance

Conference Call Information

About Kiniksa

Kiniksa is a commercial-stage biopharmaceutical company focused on discovering, acquiring, developing, and commercializing therapeutic medicines for patients suffering from debilitating diseases with significant unmet medical need. Kiniksa’s immune-modulating assets, ARCALYST, abiprubart, and mavrilimumab, are based on strong biologic rationale or validated mechanisms, target a spectrum of underserved cardiovascular and autoimmune conditions, and offer the potential for differentiation. For more information, please visit www.kiniksa.com.

About ARCALYST

ARCALYST is a weekly, subcutaneously injected recombinant dimeric fusion protein that blocks interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β) signaling. ARCALYST was discovered by Regeneron Pharmaceuticals, Inc. (Regeneron) and is approved by the U.S. Food and Drug Administration (FDA) for recurrent pericarditis, cryopyrin-associated periodic syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome and Muckle-Wells Syndrome, and deficiency of IL-1 receptor antagonist (DIRA). The FDA granted Breakthrough Therapy designation to ARCALYST for the treatment of recurrent pericarditis in 2019 and Orphan Drug exclusivity to ARCALYST in 2021 for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and pediatric patients 12 years and older. The European Commission granted Orphan Drug Designation to ARCALYST for the treatment of idiopathic pericarditis in 2021.

IMPORTANT SAFETY INFORMATION ABOUT ARCALYST

For more information about ARCALYST, talk to your doctor and see the Product Information.

About Abiprubart

Abiprubart is an investigational humanized monoclonal antibody that binds to CD40 and is designed to inhibit the CD40-CD154 (CD40 ligand) interaction, a key T-cell co-stimulatory signal critical for B-cell maturation and immunoglobulin class switching and Type 1 immune responses. Kiniksa believes disrupting the CD40-CD154 co-stimulatory interaction is an attractive approach to addressing multiple autoimmune disease pathologies.

Forward-Looking Statements

This press release contains forward-looking statements. In some cases, you can identify forward looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions, although not all forward-looking statements contain these identifying words. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation, statements regarding: our expectation that ARCALYST 2024 net product revenue will be between $405 million and $415 million; our expectation that clinical development of abiprubart in Sjögren’s Disease is fully funded in our current operating plan; our expectation to remain cash flow positive on an annual basis; our beliefs about the mechanisms of our product candidates and potential impact of their approach, including that using abiprubart to disrupt the CD40-CD154 co-stimulatory interaction is an attractive approach to address multiple autoimmune disease pathologies; and our belief that all of our product candidates offer the potential for differentiation.

These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including without limitation, the following: delays or difficulty in enrollment of patients in, and activation or continuation of sites for, our clinical trials; delays or difficulty in completing our clinical trials as originally designed; potential for changes between final data and any preliminary, interim, top-line or other data from clinical trials; our inability to replicate results from our earlier clinical trials or studies; impact of additional data from us or other companies, including the potential for our data to produce negative, inconclusive or commercially uncompetitive results; potential undesirable side effects caused by our products and product candidates; our inability to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities; potential for applicable regulatory authorities to not accept our filings, delay or deny approval of any of our product candidates or require additional data or trials to support approval; our reliance on third parties as the sole source of supply of the drug substance and drug product used in our products and product candidates; raw material, important ancillary product and drug substance and/or drug product shortages; our reliance on third parties to conduct research, clinical trials, and/or certain regulatory activities for our product candidates; complications in coordinating requirements, regulations and guidelines of regulatory authorities across jurisdictions for our clinical trials; changes in our operating plan, business development strategy or funding requirements; and existing or new competition.

These and other important factors discussed in our filings with the U.S. Securities and Exchange Commission, including under the caption “Risk Factors” contained therein, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. Except as required by law, we disclaim any intention or obligation to update or revise any forward-looking statements. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.

Every Second Counts! ®

Kiniksa Investor and Media Contact

Rachel Frank

(339) 970-9437

rfrank@kiniksa.com

KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

(FORMERLY KNOWN AS KINIKSA PHARMACEUTICALS, LTD.)

SELECTED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS)

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KINIKSA PHARMACEUTICALS INTERNATIONAL, PLC

(FORMERLY KNOWN AS KINIKSA PHARMACEUTICALS, LTD.)

SELECTED CONSOLIDATED BALANCE SHEET DATA

(In thousands)

(Unaudited)