Quick answers
- What is Rilonacept used for?
- The FDA-approved label (Arcalyst, Kiniksa Pharmaceuticals (UK), Ltd., December 16, 2025) says: “ARCALYST (rilonacept) is an interleukin-1 blocker indicated for: 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 ( 1.1, 14.1 ) Maintenance of remission of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in adults and pediatric patients weighing 10 kg or more ( 1.2 …” This page is not medical advice. Talk to your doctor or pharmacist before you start, stop or change any medicine.
- Does Rilonacept have a boxed warning?
- No. None of the 1 FDA labels we found for this medicine has a boxed warning.
- Is there a shortage of Rilonacept?
- No current shortage is listed by the FDA for the products of this medicine (FDA data from October 30, 2026).
- Has Rilonacept been recalled?
- No recall linked to the products of this medicine appears in the FDA enforcement reports we use.
- Who makes Rilonacept?
- 1 company lists prescription products of Rilonacept in the FDA NDC Directory, including Kiniksa Pharmaceuticals (UK), Ltd..
What Rilonacept is used for
Quoted from the “Indications and Usage” section of the FDA-approved label.
ARCALYST (rilonacept) is an interleukin-1 blocker indicated for: 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 ( 1.1, 14.1 ) Maintenance of remission of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in adults and pediatric patients weighing 10 kg or more ( 1.2 …
— FDA label: Arcalyst, Kiniksa Pharmaceuticals (UK), Ltd., effective December 16, 2025. Read the full label on DailyMed →
This page is not medical advice. Talk to your doctor or pharmacist before you start, stop or change any medicine.
Boxed warning
A boxed warning (“black box”) is the FDA’s strongest warning on a drug label, for serious or life-threatening risks.
The label quoted above has no boxed warning.
Forms and how it is given
| Dosage forms | Injection, powder, lyophilized, for solution |
|---|---|
| Route | Subcutaneous |
| Prescription products | 1 in the FDA NDC Directory |
| Brand names | Arcalyst |
Companies that list this medicine
Labelers in the FDA NDC Directory: the company named on the package (maker or distributor), with the number of prescription products.
- Kiniksa Pharmaceuticals (UK), Ltd.1 product
FDA approval history
- BLA: Biologics License Application: how a biologic medicine (made from living cells) is approved.
| Application | Sponsor | Approved | Later changes approved |
|---|---|---|---|
| BLA125249 ARCALYST | Kiniksa Pharmaceuticals (Uk), Ltd. | February 27, 2008 | 5, latest March 10, 2026 2026: Labeling · 2021: Efficacy · 2020: Efficacy |
Shortage status
The FDA drug shortage list does not show these products.
Recalls
No recall linked to these products (by their NDC code) appears in the FDA enforcement reports.
Official identifiers
| RxCUI (RxNorm) | 763453, 763457 |
|---|---|
| SPL set ID of the quoted label | ad965f38-dd22-4607-a673-2fb92f3b527a |
| FDA labels (SPL) | 1 |
| FDA applications | BLA125249 |
| Active ingredients (FDA) | RILONACEPT |
Sources
- FDA-approved label on DailyMed (National Library of Medicine) — Arcalyst, Kiniksa Pharmaceuticals (UK), Ltd., effective December 16, 2025; via openFDA, FDA data exported October 30, 2026, retrieved October 31, 2026
- NDC Directory (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
- Drugs@FDA (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
- Drug recall enforcement reports (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 27, 2026, retrieved October 31, 2026
- Drug shortages (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
openFDA data is provided by the FDA as is; it may be incomplete. Always rely on the label that comes with your medicine. FDA Enforcement Report search →