Company Description
Kiniksa Pharmaceuticals International, plc (Nasdaq: KNSA) is a biopharmaceutical company that focuses on discovering, acquiring, developing, and commercializing novel therapies for diseases with unmet need, with a particular emphasis on cardiovascular indications. According to multiple company disclosures, Kiniksa’s portfolio is built around assets with strong biologic rationale or validated mechanisms and is intended to offer the potential for differentiation in serious and often debilitating conditions.
The company’s lead commercial asset is ARCALYST (rilonacept), described as 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. and is approved by the U.S. Food and Drug Administration (FDA) for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older. It is also approved for Cryopyrin‑Associated Periodic Syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome (FCAS) and Muckle‑Wells Syndrome (MWS) in adults and children 12 years and older, and for the maintenance of remission of Deficiency of Interleukin‑1 Receptor Antagonist (DIRA) in adults and pediatric patients weighing 10 kg or more.
Regulatory designations highlight the niche focus of Kiniksa’s portfolio. The FDA granted Breakthrough Therapy designation to ARCALYST for the treatment of recurrent pericarditis in 2019 and Orphan Drug Exclusivity in 2021 for 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. These designations underscore the emphasis on rare, serious inflammatory and cardiovascular‑related conditions.
Beyond ARCALYST, Kiniksa is advancing investigational monoclonal antibody programs that target the interleukin‑1 pathway. KPL‑387 is described as an independently developed, fully human immunoglobulin G2 (IgG2) monoclonal antibody that binds human interleukin‑1 receptor 1 (IL‑1R1), inhibiting the signaling of IL‑1α and IL‑1β. The company is conducting a Phase 2/3 clinical trial of KPL‑387 in recurrent pericarditis, including a dose‑focusing Phase 2 portion and a pivotal Phase 3 portion with long‑term extensions. Kiniksa has stated that KPL‑387 has a target profile of monthly dosing via a single subcutaneous injection in a liquid formulation, and the U.S. FDA granted Orphan Drug Designation to KPL‑387 for the treatment of pericarditis, which includes recurrent pericarditis.
KPL‑1161 is another independently developed, investigational Fc‑modified IgG2 monoclonal antibody that binds IL‑1R1, also inhibiting IL‑1α and IL‑1β signaling. Kiniksa reports that KPL‑1161 has a target profile of quarterly subcutaneous dosing and is in preclinical or IND‑enabling development activities. Together, ARCALYST, KPL‑387, and KPL‑1161 form an IL‑1α and IL‑1β inhibition franchise that the company positions around recurrent pericarditis and related indications.
Public updates from Kiniksa emphasize execution across both commercial and clinical activities. The company reports that ARCALYST net product revenue has grown year over year and that adoption of IL‑1α and IL‑1β inhibition in recurrent pericarditis has led to an increasing number of prescribers and extended average duration of therapy. Kiniksa also notes that a portion of the estimated multiple‑recurrence recurrent pericarditis population is actively on ARCALYST treatment, and that prescribers have written thousands of ARCALYST prescriptions since launch for recurrent pericarditis.
From a financial and corporate perspective, Kiniksa has disclosed that it is listed on The Nasdaq Global Select Market under the symbol KNSA and that it is incorporated in England and Wales. Recent company communications highlight that Kiniksa has maintained a cash, cash equivalents, and short‑term investments position alongside no debt, and that management expects its current operating plan to remain cash flow positive on an annual basis. These statements are based on company guidance and are subject to the risks and uncertainties described in its SEC filings.
Kiniksa regularly participates in healthcare and investor conferences, such as the J.P. Morgan Healthcare Conference, Jefferies Global Healthcare Conference, and other sector‑focused events. The company uses these venues, along with earnings press releases and Form 8‑K filings, to provide updates on ARCALYST commercialization, clinical progress for KPL‑387 and KPL‑1161, and its overall strategy in cardiovascular‑focused biopharmaceutical development.
Overall, Kiniksa Pharmaceuticals International, plc presents itself as a biopharmaceutical issuer concentrating on IL‑1 pathway modulation for cardiovascular and inflammatory diseases with unmet need, combining an FDA‑approved product, ARCALYST, with a pipeline of investigational monoclonal antibodies, KPL‑387 and KPL‑1161, that share a common mechanistic focus on IL‑1α and IL‑1β signaling.
Stock Performance
Kiniksa Pharmaceuticals International, plc (KNSA) stock last traded at $47.02, up 1.12% from the previous close. Over the past 12 months, the stock has gained 104.7%. At a market capitalization of $3.6B, KNSA is classified as a mid-cap stock with approximately 76.5M shares outstanding.
Latest News
Kiniksa Pharmaceuticals International, plc has 10 recent news articles. Of the recent coverage, 3 articles coincided with positive price movement and 7 with negative movement. Key topics include earnings, earnings date, conferences, clinical trial. View all KNSA news →
SEC Filings
Kiniksa Pharmaceuticals International, plc has filed 5 recent SEC filings, including 2 Form 4, 2 Form 144, 1 Form SCHEDULE 13G. The most recent filing was submitted on March 11, 2026. SEC filings provide transparency into a company's financial condition, material events, and regulatory compliance. View all KNSA SEC filings →
Insider Radar
Insider selling at Kiniksa Pharmaceuticals International, plc over the past 90 days can reflect routine portfolio management, scheduled trading plans (Rule 10b5-1), tax planning, or compensation-related dispositions rather than a directional view on the stock.
Financial Highlights
Kiniksa Pharmaceuticals International, plc generated $677.6M in revenue over the trailing twelve months, retaining a 88.5% gross margin, operating income reached $77.2M (11.4% operating margin), and net income was $59.0M, reflecting a 8.7% net profit margin. Diluted earnings per share stood at $0.75. The company generated $138.0M in operating cash flow. With a current ratio of 3.79, the balance sheet reflects a strong liquidity position.
Upcoming Events
Phase 2 data readout
KPL-387 Phase 2 readout
Phase 2 data readout
Phase 2 dose-focusing data
Phase 2 data readout
KPL-387 Phase 2 data
Phase 2 trial data release
KPL-387 Phase 2 data
Release KPL-387 Phase 2 data
Phase 2 data readout
Kiniksa Pharmaceuticals International, plc has 12 upcoming scheduled events. The next event, "Phase 2 data readout", is scheduled for July 1, 2026 (in 105 days). Investors can track these dates to stay informed about potential catalysts that may affect the KNSA stock price.
Short Interest History
Short interest in Kiniksa Pharmaceuticals International, plc (KNSA) currently stands at 3.1 million shares, down 8.8% from the previous reporting period, representing 6.9% of the float.
Days to Cover History
Days to cover for Kiniksa Pharmaceuticals International, plc (KNSA) currently stands at 4.2 days, down 8.7% from the previous period. This days-to-cover ratio represents a balanced liquidity scenario for short positions. The days to cover has decreased 31.7% over the past year, suggesting improved liquidity for short covering. The ratio has shown significant volatility over the period, ranging from 1.4 to 9.2 days.
KNSA Company Profile & Sector Positioning
Kiniksa Pharmaceuticals International, plc (KNSA) operates in the Drug Manufacturers - Specialty & Generic industry within the broader Pharmaceutical Preparations sector and is listed on the NASDAQ.
Investors comparing KNSA often look at related companies in the same sector, including Hutchmed (China) Limited (HCM), Supernus Pharma (SUPN), Indivior Pharmaceuticals Inc. (INDV), Bausch Health Companies Inc (BHC), and Alvotech (ALVO). Comparing financial metrics, valuation ratios, and stock performance across these peers can help investors evaluate KNSA's relative position within its industry.