Kiniksa Pharmaceuticals International, PLC KNSA

What this company does

Kiniksa Pharmaceuticals International, plc develops and commercializes therapies for diseases with unmet need, with a focus on cardiovascular indications. Its approved product, ARCALYST, is an interleukin-1α and interleukin-1β cytokine trap. It 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, a disease with an estimated prevalent population in the United States of approximately 40,000 patients seeking and receiving medical treatment. As of December 31, 2025, it had 366 full-time employees, of which 351 were located within the United States and 15 were located outside of the United States. It is also developing KPL-387, an investigational, fully human monoclonal antibody that binds interleukin-1 receptor 1 and inhibits IL-1α- and IL-1β-mediated signaling. It was initially incorporated under the laws of Bermuda in July 2015 and, in June 2024, completed a change of place of incorporation of its principal holding company from Bermuda to the United Kingdom.

Written from the business description in Kiniksa Pharmaceuticals International, plc's annual report to the U.S. Securities and Exchange Commission, filed 24 February 2026. Every sentence was checked against that document before publication.