Kiniksa Pharmaceuticals Provides Corporate Update
Rhea-AI Summary
Kiniksa Pharmaceuticals (NASDAQ: KNSA) reported unaudited ARCALYST net product revenue of $677.5M in 2025, ~62% year-over-year growth, and expects 2026 ARCALYST revenue of $900M–$920M. Gross-to-net was 8.4% in 2025 vs 9.8% in 2024, reflecting Inflation Reduction Act impacts and fourth-quarter reserve adjustments. As of Dec 31, 2025, cash, cash equivalents and short-term investments totaled $414.1M
Positive
- ARCALYST revenue of $677.5M in 2025 (+~62% YoY)
- 2026 ARCALYST revenue guidance of $900M–$920M
- Cash, cash equivalents and short-term investments of $414.1M with no debt
- 4,150+ prescribers have written ARCALYST prescriptions
Negative
- Gross-to-net compression affected by the Inflation Reduction Act and reserve adjustments (2025 gross-to-net 8.4%)
- Concentration risk: ARCALYST drives the company’s reported product revenue
News Market Reaction
On the day this news was published, KNSA declined 3.63%, reflecting a moderate negative market reaction. Our momentum scanner triggered 2 alerts that day, indicating moderate trading interest and price volatility. This price movement removed approximately $110M from the company's valuation, bringing the market cap to $2.92B at that time.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Market Reality Check
Peers on Argus
KNSA gained 2.25% while key peers were flat-to-down: HCM 0%, SUPN -1.71%, INDV -0.23%, BHC -4.63%, ALVO -3.13%. Moves diverge from peers, indicating a stock-specific reaction to the update.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Jan 07 | Conference presentation | Neutral | -1.6% | Announcement of JPM Healthcare Conference presentation and webcast access. |
| Nov 12 | Conference presentation | Neutral | -0.7% | Jefferies London healthcare conference appearance and webcast details. |
| Oct 28 | Earnings and pipeline | Positive | -2.9% | Q3 2025 beat, raised ARCALYST guidance, profitability, and cash increase. |
| Oct 23 | Earnings scheduling | Neutral | +0.4% | Notice of upcoming Q3 results call and webcast logistics. |
| Oct 17 | Regulatory designation | Positive | -0.7% | FDA Orphan Drug Designation for KPL-387 in pericarditis. |
Recent history shows several positive fundamental updates followed by mildly negative next-day moves, suggesting a tendency for news-driven gains to be faded.
Over the past few months, Kiniksa reported strong ARCALYST growth, profitability, and pipeline progress. On Oct 28, 2025, Q3 results highlighted higher revenue, net income, and increased cash, yet the stock fell 2.88%. Orphan Drug Designation for KPL-387 on Oct 17, 2025 also saw a small negative move. Conference and presentation notices on Oct 23, Nov 12, and Jan 7 prompted minimal price changes. Today’s corporate update extends this trajectory of ARCALYST growth and IL‑1 pipeline advancement.
Market Pulse Summary
This announcement underscores Kiniksa’s transition into a cash-generating commercial story anchored by ARCALYST and an IL‑1–focused pipeline. Management reported 2025 ARCALYST revenue of $677.5M with 62% growth, 2026 guidance of $900–$920M, and cash of $414.1M. Investors may track execution against this guidance, uptake beyond the current 18% of multiple‑recurrence patients, and upcoming KPL‑387 and KPL‑1161 clinical milestones in 2026.
Key Terms
il-1α medical
cytokine medical
monoclonal antibody medical
fc-modified medical
subcutaneous medical
phase 2/3 medical
first-in-human medical
AI-generated analysis. Not financial advice.
– ARCALYST® (rilonacept) 2025 net product revenue of
– ARCALYST 2026 net product revenue expected to be
– KPL-387 Phase 2 recurrent pericarditis data expected in 2H 2026 –
– KPL-1161 Phase 1 trial planned to initiate by year end –
– Cash balance increased by
LONDON, Jan. 12, 2026 (GLOBE NEWSWIRE) -- Kiniksa Pharmaceuticals International, plc (Nasdaq: KNSA) (Kiniksa), a biopharmaceutical company developing and commercializing novel therapies for diseases with unmet need, with a focus on cardiovascular indications, today provided a corporate update.
“IL-1α & IL-1β inhibition with ARCALYST is increasingly becoming the preferred second line treatment for patients with recurrent pericarditis. As of the end of 2025, approximately
Portfolio Execution
ARCALYST (IL-1α and IL-1β cytokine trap)
- ARCALYST net product revenue was
$677.5 million (unaudited) for the full year 2025, compared to$417.0 million for the full year 2024, representing approximately62% year-over-year growth.- Gross-to-net was
8.4% (unaudited) for the full year 2025 compared to9.8% for the full year 2024, due to the impact of the Inflation Reduction Act throughout 2025, as well as prior period reserve adjustments in the fourth quarter of 2025.
- Gross-to-net was
- As of the end of the fourth quarter of 2025, approximately
18% of the 14,000 multiple-recurrence patients were actively on ARCALYST treatment. - Since launch, more than 4,150 prescribers have written ARCALYST prescriptions for recurrent pericarditis.
- Average total duration of ARCALYST therapy in recurrent pericarditis continues to grow and is approaching 3 years, in line with the median duration of disease.
- Kiniksa expects 2026 ARCALYST net product revenue of between
$900 million and$920 million .
KPL-387 (monoclonal antibody IL-1 receptor antagonist)
- Kiniksa is conducting a Phase 2/3 clinical trial of KPL-387 in recurrent pericarditis and expects data from the dose-focusing portion in the second half of 2026.
- Kiniksa is conducting a supplemental Phase 2 Transition to KPL-387 Monotherapy Dosing & Administration Study evaluating the efficacy and safety of the dosing regimens used to transition patients from standard therapies to KPL-387 monotherapy.
KPL-1161 (Fc-modified monoclonal antibody IL-1 receptor antagonist)
- Kiniksa is conducting preclinical development activities with KPL-1161 with a target profile of quarterly subcutaneous (SC) dosing. The company expects to initiate a Phase 1 first-in-human clinical trial by the end of 2026.
Corporate Update
- As of December 31, 2025, Kiniksa had
$414.1 million of cash, cash equivalents, and short-term investments and no debt (unaudited). - Kiniksa expects its current operating plan to remain cash flow positive on an annual basis.
44th Annual J.P. Morgan Healthcare Conference
- Sanj K. Patel, Chairman and Chief Executive Officer of Kiniksa and Ross Moat, Chief Corporate and Commercial Officer, will provide a corporate presentation at the 44th Annual J.P. Morgan Healthcare Conference on January 12, 2026, at 2:15 p.m. Pacific Time (5:15 p.m. Eastern Time). A live webcast of Kiniksa’s presentation will be accessible through the Investors & Media section of the company’s website at www.kiniksa.com. A replay of the webcast will also be available on Kiniksa’s website within approximately 48 hours after the event.
About Kiniksa
Kiniksa is a biopharmaceutical company dedicated to improving the lives of patients suffering from debilitating diseases by discovering, acquiring, developing, and commercializing novel therapies for diseases with unmet need, with a focus on cardiovascular indications. Kiniksa’s portfolio of assets is based on strong biologic rationale or validated mechanisms and offers 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 the treatment of recurrent pericarditis (RP) and reduction in risk of recurrence in adults and children 12 years and older. ARCALYST is also approved by the FDA for the treatment of 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 the maintenance of remission of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in adults and pediatric patients weighing 10 kg or more. The FDA granted Orphan Drug Exclusivity to ARCALYST upon its approval for recurrent pericarditis in 2021. The European Commission granted Orphan Drug Designation to ARCALYST for the treatment of idiopathic pericarditis in 2021.
IMPORTANT SAFETY INFORMATION ABOUT ARCALYST
- ARCALYST may affect your immune system and can lower the ability of your immune system to fight infections. Serious infections, including life-threatening infections and death, have happened in patients taking ARCALYST. If you have any signs of an infection, call your doctor right away. Treatment with ARCALYST should be stopped if you get a serious infection. You should not begin treatment with ARCALYST if you have an infection or have infections that keep coming back (chronic infection).
- While taking ARCALYST, do not take other medicines that block interleukin-1, such as Kineret® (anakinra), or medicines that block tumor necrosis factor, such as Enbrel® (etanercept), Humira® (adalimumab), or Remicade® (infliximab), as this may increase your risk of getting a serious infection.
- Talk with your doctor about your vaccine history. Ask your doctor whether you should receive any vaccines before you begin treatment with ARCALYST.
- Medicines that affect the immune system may increase the risk of getting cancer.
- Stop taking ARCALYST and call your doctor or get emergency care right away if you have any symptoms of an allergic reaction.
- Your doctor will do blood tests to check for changes in your blood cholesterol and triglycerides.
- Common side effects include injection-site reactions (which may include pain, redness, swelling, itching, bruising, lumps, inflammation, skin rash, blisters, warmth, and bleeding at the injection site), upper respiratory tract infections, joint and muscle aches, rash, ear infection, sore throat, and runny nose.
For more information about ARCALYST, talk to your doctor and see the Product Information.
About KPL-387
KPL-387 is an independently developed, investigational, fully human immunoglobulin G2 (IgG2) monoclonal antibody that binds human interleukin-1 receptor 1 (IL-1R1), inhibiting the signaling of the cytokines IL-1α and IL-1β. Kiniksa believes KPL-387 could expand the treatment options for recurrent pericarditis patients by potentially enabling dosing with a single monthly SC self-injection in a liquid formulation. In October 2025, the FDA granted Orphan Drug Designation to KPL-387 for the treatment of pericarditis.
About KPL-1161
KPL-1161 is an independently developed, investigational, Fc-modified IgG2 monoclonal antibody that binds IL-1R1, inhibiting the signaling of the cytokines IL-1α and IL-1β, with a target profile of quarterly SC dosing. Kiniksa is currently engaging in preclinical development activities for KPL-1161.
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 2026 net product revenue will be between
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; business development activities and their impact on our financial performance and strategy; changes in our operating plan, business development strategy or funding requirements; existing or new competition; current and future healthcare reforms, including those affecting the delivery of or payment for healthcare products and services; and the impact of global economic policy, including any uncertainty in national and international markets.
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.
ARCALYST® is a registered trademark of Regeneron Pharmaceuticals, Inc.
Every Second Counts! ®
Kiniksa Investor & Media Contact
Jonathan Kirshenbaum
(781) 829-3949
jkirshenbaum@kiniksa.com
FAQ
What were Kiniksa (KNSA) ARCALYST revenues for full-year 2025?
What ARCALYST revenue does Kiniksa (KNSA) expect for 2026?
When does Kiniksa expect KPL-387 clinical data and what trial phase is it?
When will Kiniksa (KNSA) start first-in-human trials for KPL-1161?
How strong is Kiniksa’s cash position as of Dec 31, 2025?
How much of the multiple-recurrence pericarditis population is on ARCALYST?
