Rilonacept: uses, dosing, side effects & brands
Rilonacept is a medicine sold in the U.S. under one brand, for inflammation and inborn genetic diseases. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats
- Inflammation and Inborn Genetic Diseases
- Available as
- Injectable
- Sold as
- Arcalyst
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How rilonacept is dosed
From the FDA label for Arcalyst (application BLA125249). Other rilonacept products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Administer by subcutaneous injection ( 2.1 ) CAPS, FCAS, MWS, and RP ( 2.2 ): Adults: – Loading dose: 320 mg, delivered as two 160 mg (2 mL) injections. – Maintenance dose: 160 mg (2 mL) injection once weekly. Pediatric patients 12 years to 17 years: – Loading dose: 4.4 mg/kg, up to a maximum of 320 mg, delivered as 1 or 2 injections (not to exceed 2 mL/injection). – Maintenance dose: 2.2 mg/kg, up to a maximum of 160 mg (2 mL) injection, once weekly. DIRA ( 2.3 ): Adults and pediatric patients weighing 10 kg or more: – 4.4 mg/kg up to a maximum of 320 mg, delivered as 1 or 2 injections (2 mL/injection) once weekly. 2.1 General Dosing Information ARCALYST is for subcutaneous use only. 2.2 Cryopyrin-Associated Periodic Syndromes, Familial Cold Autoinflammatory Syndrome, Muckle-Wells Syndrome and Recurrent Pericarditis Adults : Initiate treatment with a loading dose of 320 mg delivered as two, 2-mL subcutaneous injections of 160 mg each, administered on the same day at two different injection sites. Continue dosing with a once-weekly injection of 160 mg administered as a single, 2-mL subcutaneous injection. Pediatric patients 12 years to 17 years : Initiate treatment with a loading dose of 4.4 mg/kg, up to a maximum dose of 320 mg, administered as one or two subcutaneous injections, not to exceed single-injection volume of 2 mL per injection site. If the initial dose is given as…
Rilonacept side effects
The following clinically significant adverse reactions are described elsewhere in the labeling. Serious Infections [see Warnings and Precautions (5.1) ] Risk of Malignancy [see Warnings and Precautions (5.2) ] Hypersensitivity Reactions [see Warnings and Precautions (5.3) ] Lipid Profile Changes [see Warnings and Precautions (5.4) ] The most common adverse reactions reported by patients with CAPS and RP treated with ARCALYST are injection-site reactions and upper respiratory tract infections. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Kiniksa at 1-833-KINIKSA (1-833-546-4572) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trial Experience Clinical trials are conducted under widely varying conditions and, as such, adverse reaction rates observed cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The data described herein reflect exposure to ARCALYST in over 2,000 patients who received at least one dose, including approximately 1700 exposed to 160 mg or more, of whom 151 patients were exposed for at least 6 months and 111 patients for at least one year. These included patients with CAPS and RP, patients with other diseases, and healthy volunteers. CAPS Approximately 60 patients with CAPS were treated weekly with 160 mg of ARCALYST. The pivotal trial population…
Who shouldn’t take rilonacept
None. None. ( 4 )
Rilonacept drug interactions
7.1 TNF-Blocking Agent and IL-1 Blocking Agent Specific drug interaction studies have not been conducted with ARCALYST. Concomitant administration of another drug that blocks IL-1 with a TNF-blocking agent in another patient population has been associated with an increased risk of serious infections and an increased risk of neutropenia. The concomitant administration of ARCALYST with TNF-blocking agents may also result in similar toxicities and is not recommended [see Warnings and Precautions (5.1) ] . The concomitant administration of ARCALYST with other drugs that block IL-1 has not been studied. Based upon the potential for pharmacologic interactions between rilonacept and a recombinant IL-1ra, concomitant administration of ARCALYST and other agents that block IL-1 or its receptors is not recommended. 7.2 Cytochrome P450 Substrates The formation of CYP450 enzymes is suppressed by increased levels of cytokines (e.g., IL-1) during chronic inflammation. Thus it is expected that for a molecule that binds to IL-1, such as rilonacept, the formation of CYP450 enzymes could be normalized. This is clinically relevant for CYP450 substrates with a narrow therapeutic index, where the dose is individually adjusted (e.g., warfarin). Upon initiation of ARCALYST in patients being treated with these types of medicinal products, therapeutic monitoring of the effect or drug concentration should be performed, and the individual dose of the medicinal product may need to be adjusted.
Every rilonacept product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Arcalyst.
What people report to the FDA about rilonacept
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 107 reports naming rilonacept, and the FDA flagged 80% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- interstitial lung disease9 reports
- arthralgia8 reports
- drug reaction with eosinophilia and systemic symptoms8 reports
- pericardial effusion8 reports
- pyrexia8 reports
- gingival hyperplasia7 reports
- hirsutism7 reports
- hypertension7 reports
Read these as a signal, not a rate. A report does not mean rilonacept caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 26, 2026.
Related calculators
Frequently asked questions
What is rilonacept?
Rilonacept is a dimeric fusion protein consisting of the ligand-binding domains of the extracellular portions of the human interleukin-1 receptor component (IL-1R1) and IL-1 receptor accessory protein (IL-1RAcP) linked in-line to the Fc portion of human IgG1.
Can you take rilonacept with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run rilonacept against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does rilonacept come in?
Across the brands we track, rilonacept is currently marketed as injectable, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic rilonacept?
We do not currently list a generic-labelled rilonacept product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Rilonacept: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/rilonacept
- MLA
- “Rilonacept: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/rilonacept.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for rilonacept on DailyMed (NIH) ↗.