Home › NDC Lookup › Ingredients › Rilonacept › 73604-0914-04
Arcalyst rilonacept 160 mg/2mL Injection, Powder, Lyophilized, For Solution — NDC 73604-0914-04 package photo
Label image from the product's FDA listing (DailyMed) — may show a different pack size or an older label revision.

Arcalyst rilonacept 160 mg/2mL Injection, Powder, Lyophilized, For Solution — NDC 73604-914-04 (Billing 73604-0914-04)

by Kiniksa Pharmaceuticals (UK), Ltd. · 4 VIAL, SINGLE-USE in 1 CARTON / 2 mL in 1 VIAL, SINGLE-USE

This is a package of Arcalyst rilonacept 160 mg/2mL Injection, Powder, Lyophilized, For Solution from Kiniksa Pharmaceuticals (UK), Ltd., marketed since Feb 2008 and currently FDA-listed. It is the main listing for this product, which comes in 2 package sizes.

NDC 73604-0914-04
🏷️ FDA NDC (as labeled) 73604-914-04 billing pads the product segment with a zero
This package
Contains2 mL in 1 vial, single-use Medicaid pays$6,013.03 / unit · 12 mo Per package$48,104.20 / 8 ml · Medicaid Pack sizes2 compare ↓
Also priced by: Part D plans $6,380.96/unit — full pricing hub ↓
Main listing for product 73604-914 · Also comes in: 2 mL 73604-914-01
Rx only Brand On market Non-controlled ⇄ Compare with another NDC
🗂️ FDA directory synced Oct 1, 2026 · this listing last changed Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

NDC database record

One package, one record: these facts belong to NDC 73604-914-04 alone.

Record
FDA NDC Directory package listing · Human prescription drug
Code segments
73604 labeler · 914 product · 04 package
Package marketed since
Mar 24, 2008
Sample package
No — commercial package
Listing certified through
Dec 31, 2026
Barcode (UPC-A, from the NDC)
3 7360491404 3
Medicaid fills, this package
2,276 prescriptions in the last four reported quarters
FDA record last changed
Jul 24, 2026

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

FDA NDC (as labeled) 73604-914-04
Product NDC 73604-914
11-digit billing NDC 73604091404
NCPDP billing unit EA — each (per item)
RxCUI 763453, 763457
UNII 8K80YB5GMG
Application # BLA125249
SPL Set ID ad965f38-dd22-4607-a673-2fb92f3b527a
DEA schedule Non-controlled
Marketing category BLA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2008-02-27
Route SUBCUTANEOUS
Dosage form INJECTION, POWDER, LYOPHILIZED, FOR SOLUTION
Substance RILONACEPT
Biologic (Purple Book) 351(a)

Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification

GPI-14 66450060002120
GPI class Arcalyst
GCN Seq No 063759
GCN 99473
HICL code 035438
Ingredient (HICL) Rilonacept
HIC1 code S
Therapeutic class — broad (HIC1) Locomotor System
HIC2 code S2
Therapeutic class — intermediate (HIC2) Drugs Acting Principally On Joints
HIC3 code S2M
Therapeutic class — specific (HIC3) Anti-Inflam. Interleukin-1 Receptor Antagonist
AHFS code 48:10.20.00
AHFS class Interleukin Antagonists
FDB label name ARCALYST 220 MG VIAL
FDB brand name Arcalyst
Legend status F — Federal legend — prescription drug or device
Quick answers
  • GSN (GCN sequence number): 063759
  • GCN: 99473
  • GPI-14 (Medi-Span): 66450060002120
  • HICL (First Databank): 035438
  • AHFS class code: 48:10.20.00
  • RxCUI (RxNorm): 763453
Why two NDCs? The FDA registers this code as 73604-914-04 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 73604-0914-04. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

RxNorm drug class

This medicine belongs to the Interleukin inhibitors class.

Drug family (ATC) Interleukin inhibitors
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

Clinical

Label name ARCALYST 220 MG VIAL Ingredient Rilonacept
📖 What it is MedlinePlus · NLM

Rilonacept injection is used to treat cryopyrin-associated periodic syndromes (CAPS; inherited conditions in which the body attacks its own tissues causing inflammation, joint and muscle pain, rash or other skin lesions, fever and chills, eye redness or pain, and fatigue), including familial cold autoinflammatory syndrome (FCAS), and Muckle-Wells syndrome (MWS) in adults and children 12 years of age or older. Rilonacept injection is also used to treat deficiency of interleukin-1 receptor antagonist (DIRA; a disorder in which the body attacks its own tissues causing inflammation and damages bon...

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Arcalyst is neither a steroid nor a traditional immunotherapy. It's a targeted biologic — a protein designed to block two specific inflammatory signals called IL-1α and IL-1β that...
  • What exactly is Arcalyst treating — is it a steroid or immunotherapy?
  • Arcalyst comes as a powder that you mix with sterile water before injecting it just under the skin — a subcutaneous injection, similar to an insulin shot. The most common complaint...
  • How do I give myself the injection, and does it hurt?
📖 Read our full Rilonacept Injection guide →

Supplement & herbal interactions

🌿 Drug–supplement interaction checker →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer mLPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo $6,013.03 $48,104.20 / 8 ml
Medicare drug plans payPart D · Q2 2026 $6,380.96 $51,047.66 / 8 ml
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

Packaging — all sizes for this product

Package NDCDescription Marketing startMarketing endStatus
73604-0914-01 73604-914-01 1 VIAL, SINGLE-USE in 1 CARTON / 2 mL in 1 VIAL, SINGLE-USE 2021-06-18 — Active
73604-0914-04 You're viewing this Main listing 4 VIAL, SINGLE-USE in 1 CARTON / 2 mL in 1 VIAL, SINGLE-USE 2008-03-24 — Active

In Medicaid, this is the most-dispensed pack of this product — about 100% of fills over the last four reported quarters. See all packs ↓

Pack size FAQ

What quantity is in this package?
This package is listed by the FDA — 4 vial, single-use in 1 carton / 2 ml in 1 vial, single-use.
What NDC number is used to bill for this package of Arcalyst rilonacept 160 mg/2mL Injection, Powder, Lyophilized, For Solution?
Use the 11-digit billing form listed in the identifiers section of this page. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Arcalyst 160 mg/2mLthis 73604-0914-04 Kiniksa 4 vials — — FDA listed —
About this product: this is a biologic. Biologics don't have small-molecule generics — competition comes from FDA-licensed biosimilars (shown above), not generics.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

Availability & biosimilar status

🏛️
2008
First FDA approval
Feb 2008
📍
2026
Currently FDA-listed
18 years listed
🧬
·
Biosimilars
see Purple Book
🧬Biologic — competition comes from biosimilars

Biologics have no small-molecule generics; biosimilar competition is tracked in the FDA Purple Book.

FDA Purple Book — biosimilars & interchangeables ⓘ
Reference product
Arcalystrilonacept
🔒 No FDA-licensed biosimilars or interchangeable biosimilars are listed yet for this biologic. It currently has no biosimilar competition in the FDA Purple Book.
Source: FDA Purple Book (purplebooksearch.fda.gov), matched on the reference product’s active ingredient.
Where does this data come from?
Patents and exclusivity from the FDA Purple Book (biologics), refreshed from public FDA data. Biosimilar launch timing is an estimate, not a guarantee.

Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII 94ZLA3W45F
    Arginine is an amino acid used in medicines as a buffer and pH adjuster. It helps maintain the proper acidity level and stability of liquid formulations.
  • UNII TE7660XO1C
    Glycine is an amino acid used in medicines as a buffer to help stabilize pH and improve taste. It may also serve as a filler or binder to give the product proper form and consistency.
  • UNII 4QD397987E
    An amino acid used as a buffer and stabilizer in medications. It helps maintain the pH balance and protects the active drug from breaking down during storage and use.
  • UNII G2M7P15E5P
    Polyethylene glycol 3350 is a synthetic polymer used as a solvent, humectant, and thickening agent in medicines. It helps dissolve other ingredients, retain moisture in the product, and achieve the desired consistency.
  • UNII C151H8M554
    A natural sugar derived from sugar cane or sugar beets. It's used as a sweetener, filler, and binder to improve taste, add bulk, and help hold tablet or capsule ingredients together.

5 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

Manufacturer & labeler

LabelerKiniksa Pharmaceuticals (UK), Ltd.
FDA applicationBLA125249 (BLA)
Labeler code73604
First marketedFeb 2008
Product typeHuman Prescription Drug
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Very long sections are excerpted here and marked; the full text is on DailyMed (linked in the sources below). Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 🔄 Drug Interactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📦 Storage and Handling 📋 Description 💬 Information for Patients 🧬 Pharmacokinetics 🧬 Pharmacodynamics 🔬 Clinical Studies 🧪 Nonclinical Toxicology 📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 📄 Patient Package Insert 📖 Instructions for Use 📄 Recent Major Changes 📄 Package Label / Principal Display Panel
🎯 Indications and Usage 195 words ▾

1 INDICATIONS AND USAGE 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 , 14.2 ) Treatment of recurrent pericarditis (RP) and reduction in risk of recurrence in adults and children 12 years and older ( 1.3 , 14.3 )

1.1Cryopyrin-Associated Periodic Syndromes, Familial Cold Autoinflammatory Syndrome and Muckle-Wells Syndrome ARCALYST ® (rilonacept) is an interleukin-1 blocker indicated for the treatment of Cryopyrin-Associated Periodic Syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome (FCAS), and Muckle-Wells Syndrome (MWS) in adults and pediatric patients 12 years and older.

1.2Deficiency of IL-1 Receptor Antagonist ARCALYST is indicated for the maintenance of remission of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in adults and pediatric patients weighing at least 10 kg.

1.3Recurrent Pericarditis ARCALYST is indicated for the treatment of recurrent pericarditis (RP) and reduction in risk of recurrence in adults and pediatric patients 12 years and older.

⏱️ Dosage and Administration ~3 min read ▾

2 DOSAGE AND ADMINISTRATION 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.

2.1General Dosing Information ARCALYST is for subcutaneous use only.

2.2Cryopyrin-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 two injections, administer on the same day at two different sites. Continue dosing with a once-weekly injection of 2.2 mg/kg, up to a maximum of 160 mg, administered as a single subcutaneous injection, up to 2 mL. If a once-weekly dose is missed, instruct the patient to administer the injection within 7 days from the missed dose and then resume the patient's original schedule.

If the missed dose is not administered within 7 days, instruct the patient to administer the dose, starting a new schedule based on this date.

2.3Deficiency of IL-1 Receptor Antagonist Adults : The recommended dose of ARCALYST is 320 mg, once weekly, administered as two subcutaneous injections on the same day at two different sites with a maximum single-injection volume of 2 mL. ARCALYST should not be given more often than once weekly. Pediatric patients weighing 10 kg or more : The recommended dose of ARCALYST is 4.4 mg/kg (up to a maximum of 320 mg), once weekly, administered as one or two subcutaneous injections with a maximum single-injection volume of 2 mL.

If the dose is given as two injections, administer both on the same day, each one at a different site. When switching from another IL-1 blocker, discontinue the IL-1 blocker and begin ARCALYST treatment at the time of the next dose [see Drug Interactions (7.1) ] .

2.4Preparation for Administration Reconstitute each single-dose vial of ARCALYST with 2.3 mL of preservative-free Sterile Water for Injection, USP (supplied separately) prior to subcutaneous administration of the drug.

2.5Administration Using aseptic technique, withdraw 2.3 mL of preservative-free Sterile Water for Injection through an 18-gauge, 1- or 1½-inch needle attached to a 3-mL syringe and inject the preservative-free Sterile Water for Injection, USP, into the drug product vial for reconstitution. The needle and syringe used for reconstitution with preservative-free Sterile Water for Injection, USP, should then be discarded and should not be used for subcutaneous injections. After the addition of preservative-free Sterile Water for Injection, USP, reconstitute the vial contents by shaking the vial for approximately one minute and then allowing it to sit for one minute.

The resulting 80mg/mL solution is sufficient to allow a withdrawal volume of up to 2 mL for subcutaneous administration. The reconstituted solution is viscous, clear, colorless to pale yellow, and free from particulates. Prior to injection, inspect the reconstituted solution for any discoloration or particulate matter.

Discard the solution if either is observed.… [Excerpted — this section continues on DailyMed.]

💊 Dosage Forms and Strengths 39 words ▾

3 DOSAGE FORMS AND STRENGTHS For injection: 220 mg of rilonacept as a white to off-white lyophilized powder for reconstitution in single-dose vials. For injection: 220 mg of lyophilized powder in a single-dose vial for reconstitution. ( 3 )

⛔ Contraindications 7 words ▾

4 CONTRAINDICATIONS None. None. ( 4 )

⚠️ Warnings and Cautions ~2 min read ▾

5 WARNINGS AND PRECAUTIONS Serious Infections : Serious, life-threatening infections have been reported in patients taking ARCALYST. Do not initiate treatment with ARCALYST in patients with active or chronic infections. Discontinue treatment if a patient develops a serious infection.

( 5.1 ) Hypersensitivity Reactions : If a hypersensitivity reaction occurs, discontinue administration of ARCALYST and initiate appropriate therapy. ( 5.3 ) Immunizations : Avoid live vaccines. Update recommended vaccinations prior to initiation of therapy per current guidelines.

( 5.5 )

5.1Serious Infections Interleukin-1 (IL-1) blockade may interfere with the immune response to infections. Treatment with another medication that works through inhibition of IL-1 has been associated with an increased risk of serious infections, and serious infections have been reported in patients taking ARCALYST [see Clinical Studies (14) ] . There was a greater incidence of infections in CAPS and RP patients on ARCALYST compared with placebo.

In the controlled portion of the CAPS study [see Clinical Studies (14.1) ] , severe infection (bronchitis) was reported in one patient receiving ARCALYST. In an open-label extension study in CAPS, one patient developed bacterial meningitis and died [see Adverse Reactions (6.1) ] . In clinical studies, ARCALYST has not been administered concomitantly with tumor necrosis factor (TNF) inhibitors.

An increased incidence of serious infections has been associated with administration of an IL-1 blocker in combination with TNF inhibitors. ARCALYST is not recommended for use with TNF inhibitors because this may increase the risk of serious infections. Drugs that affect the immune system by blocking TNF have been associated with an increased risk of reactivation of latent tuberculosis (TB).

It is possible that taking drugs such as ARCALYST that block IL-1 increases the risk of TB or other atypical or opportunistic infections. Refer to current practice guidelines for evaluation and treatment of possible latent tuberculosis infections before initiating therapy with ARCALYST. Treatment with ARCALYST should not be initiated in patients with an active or chronic infection.

Discontinue ARCALYST if a patient develops a serious infection.

5.2Risk of Malignancy The impact of treatment with ARCALYST on the development of malignancies is not known. Treatment with immunosuppressants, including ARCALYST, may result in an increase in the risk of malignancies.

5.3Hypersensitivity Reactions Hypersensitivity reactions associated with ARCALYST occurred in clinical trials. If a hypersensitivity reaction occurs, discontinue ARCALYST and initiate appropriate therapy.

5.4Lipid Profile Changes Cholesterol and lipid levels may be reduced in patients with chronic inflammation. Increases in non-fasting lipid profile parameters occurred in patients treated with ARCALYST in clinical trials. Monitor patients' lipid profiles and consider lipid-lowering therapies if needed, based on cardiovascular risk factors and current guidelines [see Adverse Reactions (6.1) ] .

5.5Immunizations Since no data are available on the risks of secondary transmission of infection by live vaccines in patients receiving ARCALYST, avoid administration of live vaccines during treatment with ARCALYST. No data are available on the effectiveness of vaccines in patients receiving ARCALYST. Since ARCALYST may interfere with normal immune response to new antigens, vaccines may not be effective in patients receiving ARCALYST.

Because IL-1 blockade may interfere with immune response to infections, it is recommended that prior to initiation of therapy with ARCALYST, adult and pediatric patients receive all recommended vaccinations, as per current immunization guidelines, including pneumococcal vaccine and inactivated influenza vaccine.

🤒 Adverse Reactions ~3 min read ▾

6 ADVERSE REACTIONS 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 .

6.1Clinical 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 included 47 patients with CAPS.

These patients were between the ages of 22 and 78 years (average 51 years). Thirty-one patients were female and 16 were male. All of the patients were White/Caucasian.

Six pediatric patients (12 to17 years) were enrolled directly into the open-label extension phase of the trial. Part A of the clinical trial was conducted in patients with CAPS who were naïve to treatment with ARCALYST. Part A of the study was a randomized, double-blind, placebo-controlled, six-week study comparing ARCALYST to placebo [see Clinical Studies (14) ] .

Table 1 reflects the frequency of adverse events reported by at least two patients during Part A. Table 1: Most Frequent Adverse Reactions in Patients with CAPS (Part A, Reported by at Least Two Patients) Adverse Event ARCALYST 160 mg (n = 23) Placebo (n= 24) Any AE 17 (74%) 13 (54%) Injection-site reactions 11 (48%) 3 (13%) Upper respiratory tract infection 6 (26%) 1 (4%) Nausea 1 (4%) 3 (13%) Diarrhea 1 (4%) 3 (13%) Sinusitis 2 (9%) 1 (4%) Abdominal pain upper 0 2 (8%) Cough 2 (9%) 0 Hypoesthesia 2 (9%) 0 Stomach discomfort 1 (4%) 1 (4%) Urinary tract infection 1 (4%) 1 (4%) DIRA In a 2-year, open-label study, 6 pediatric patients with DIRA, 3 years to 6 years of age, received a 2.2 to 4.4 mg/kg dose of ARCALYST once weekly [see Clinical Studies (14.2) ] .

The safety profile was generally consistent with that seen in patients with CAPS. The most common adverse reactions were upper respiratory infection (6 of 6), rash (5 of 6), otitis media (3 of 6), pharyngitis (3 of 6) and rhinorrhea (3 of 6). RP In the RP phase 3 study, a total of 86 patients received at least one dose of ARCALYST with a median treatment duration of 9 months [see Clinical Studies (14.3) ].

Of the patients, 49 (57%) were female and 37 (43%) were male; 93% were White/Caucasian. The mean age was 44.7 years. Seven patients (8%) were aged 12-17 years old.

No new adverse reactions were identified in this study. Adverse Reactions of Special Interest Injection-Site Reactions In patients with CAPS or RP, the most common and consistently reported adverse event associated with ARCALYST was injection-site reaction (ISR). The ISRs included erythema, swelling, pruritus, mass, bruising, inflammation, pain, edema, dermatitis, discomfort, urticaria, vesicles, warmth and hemorrhage.

Most injection-site reactions lasted for one to two days. Infections During Part A in the CAPS study, the incidence of patients reporting infections was greater with ARCALYST (48%) than with placebo (17%). In Part B, randomized withdrawal, the incidenc… [Excerpted — this section continues on DailyMed.]

🔄 Drug Interactions ~1 min read ▾

7 DRUG INTERACTIONS

7.1TNF-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.

7.2Cytochrome 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.

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS Pregnancy: Based on animal data, may cause fetal harm. ( 8.1 )

8.1Pregnancy Risk Summary Rare pregnancy outcomes reported postmarketing and from clinical trials, with very limited use of ARCALYST in pregnant women, are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. There may be risks to the mother and fetus associated with Cryopyrin Associated Periodic Syndromes (CAPS) (see Clinical Considerations ) . In an animal reproduction study, subcutaneous administration of rilonacept to pregnant monkeys during the period of organogenesis was complicated by losses of drug exposure as the study progressed, due to anti-drug antibody formation at all doses, but a dose-related increase in exposure was still evident.

There were no treatment-related effects on fetal survival or development of malformations with doses up to 11 times the maximum recommended human dose (MRHD). Increased incidences of lumbar ribs, a skeletal variation, were observed in fetuses at doses approximately 2 times the MRHD and higher that slightly exceeded incidences in both control animals and the historical control database ( see Data ). There were findings of multiple fusion and absence of the ribs and thoracic vertebral bodies and arches in one fetus of the only pregnant monkey with exposure to rilonacept during the later period of gestation associated with a dose approximately 6 times the MRHD ( see Data ).

The relationship of these findings in a single fetus to drug treatment was unclear, as these findings were not evident in fetuses from pregnant monkeys that had higher exposures to rilonacept during the period of organogenesis associated with a dose approximately 11 times the MRHD. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown.

In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies is 2%–4% and of miscarriage is 15%–20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Published data suggest that increased maternal levels of interleukin (IL)-1β, which induces inflammation that occurs in CAPS, may be associated with pre-term birth. Data Animal Data In an embryo-fetal development study, pregnant cynomolgus monkeys received rilonacept at subcutaneous doses of 0, 5, 15 or 30 mg/kg given twice a week from gestation days 20 to 48.

The study was complicated by losses of drug exposure as the study progressed, due to anti-drug antibody formation at all doses, but a dose-related increase in exposure was still evident. There were no treatment-related effects on fetal survival or development of malformations with doses up to 11 times the MRHD (on a mg/kg basis with maternal subcutaneous doses up to 30 mg/kg). Increased incidences of lumbar ribs, a skeletal variation, were observed in fetuses at doses approximately 2 times the MRHD and higher (on a mg/kg basis with maternal subcutaneous doses of 5 mg/kg and higher) that slightly exceeded incidences in both control animals and the historical control database.

There were findings of multiple fusion and absence of the ribs and thoracic vertebral bodies and arches in one fetus of the only pregnant monkey with exposure to rilonacept during the later period of gestation associated with a dose 6 times the MRHD (on a mg/kg basis with a maternal subcutaneous dose of 15 mg/kg). The relationship of these findings in a single fetus to drug treatment was unclear, as these findings were not evident in fetuses from pregnant monkeys that had higher exposures to rilonacept during the period of organogenesis associated with a dose approximately 11 times the MRHD (on a mg/kg basis with a maternal subcutaneous dose of 30 mg/kg).

All doses of rilonacept reduced m… [Excerpted — this section continues on DailyMed.]

🤰 Pregnancy ~3 min read ▾

8.1Pregnancy Risk Summary Rare pregnancy outcomes reported postmarketing and from clinical trials, with very limited use of ARCALYST in pregnant women, are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. There may be risks to the mother and fetus associated with Cryopyrin Associated Periodic Syndromes (CAPS) (see Clinical Considerations ) . In an animal reproduction study, subcutaneous administration of rilonacept to pregnant monkeys during the period of organogenesis was complicated by losses of drug exposure as the study progressed, due to anti-drug antibody formation at all doses, but a dose-related increase in exposure was still evident.

There were no treatment-related effects on fetal survival or development of malformations with doses up to 11 times the maximum recommended human dose (MRHD). Increased incidences of lumbar ribs, a skeletal variation, were observed in fetuses at doses approximately 2 times the MRHD and higher that slightly exceeded incidences in both control animals and the historical control database ( see Data ). There were findings of multiple fusion and absence of the ribs and thoracic vertebral bodies and arches in one fetus of the only pregnant monkey with exposure to rilonacept during the later period of gestation associated with a dose approximately 6 times the MRHD ( see Data ).

The relationship of these findings in a single fetus to drug treatment was unclear, as these findings were not evident in fetuses from pregnant monkeys that had higher exposures to rilonacept during the period of organogenesis associated with a dose approximately 11 times the MRHD. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown.

In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies is 2%–4% and of miscarriage is 15%–20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Published data suggest that increased maternal levels of interleukin (IL)-1β, which induces inflammation that occurs in CAPS, may be associated with pre-term birth. Data Animal Data In an embryo-fetal development study, pregnant cynomolgus monkeys received rilonacept at subcutaneous doses of 0, 5, 15 or 30 mg/kg given twice a week from gestation days 20 to 48.

The study was complicated by losses of drug exposure as the study progressed, due to anti-drug antibody formation at all doses, but a dose-related increase in exposure was still evident. There were no treatment-related effects on fetal survival or development of malformations with doses up to 11 times the MRHD (on a mg/kg basis with maternal subcutaneous doses up to 30 mg/kg). Increased incidences of lumbar ribs, a skeletal variation, were observed in fetuses at doses approximately 2 times the MRHD and higher (on a mg/kg basis with maternal subcutaneous doses of 5 mg/kg and higher) that slightly exceeded incidences in both control animals and the historical control database.

There were findings of multiple fusion and absence of the ribs and thoracic vertebral bodies and arches in one fetus of the only pregnant monkey with exposure to rilonacept during the later period of gestation associated with a dose 6 times the MRHD (on a mg/kg basis with a maternal subcutaneous dose of 15 mg/kg). The relationship of these findings in a single fetus to drug treatment was unclear, as these findings were not evident in fetuses from pregnant monkeys that had higher exposures to rilonacept during the period of organogenesis associated with a dose approximately 11 times the MRHD (on a mg/kg basis with a maternal subcutaneous dose of 30 mg/kg).

All doses of rilonacept reduced maternal serum levels of estradiol up to 64% compared to controls. In pre- and postnatal devel… [Excerpted — this section continues on DailyMed.]

🧒 Pediatric Use ~1 min read ▾

8.4Pediatric Use Cryopyrin-Associated Periodic Syndromes (CAPS) and Recurrent Pericarditis (RP) Safety and effectiveness in pediatric patients with CAPS and RP below the age of 12 years have not been established. Six pediatric patients with CAPS between the ages of 12 and 16 were treated with ARCALYST at a weekly subcutaneous dose of 2.2 mg/kg (up to a maximum of 160 mg) for 24 weeks during the open-label extension phase. These patients showed improvement from baseline in their symptom scores and in objective markers of inflammation (e.g., Serum Amyloid A and C-Reactive Protein).

The adverse reactions included injection-site reactions and upper respiratory symptoms as were commonly seen in adult patients. The trough drug levels for four pediatric patients measured at the end of the weekly dose interval (mean 20 mcg/mL, range 3.6 to 33 mcg/mL) were similar to those observed in adult patients with CAPS (mean 24 mcg/mL, range 7 to 56 mcg/mL). In the Phase 3 study RHAPSODY, 7 patients aged 12 years to 17 years were treated with ARCALYST subcutaneously with an initial loading dose of 4.4 mg/kg (up to a maximum of 320 mg) followed by 2.2 mg/kg (up to a maximum of 160 mg) weekly.

These patients were treated for a median time of 15 weeks. There were no apparent differences in efficacy, safety or tolerability across age groups. When administered to pregnant primates, rilonacept treatment may have contributed to alterations in bone ossification in the fetus.

It is not known if ARCALYST will alter bone development in pediatric patients. Pediatric patients treated with ARCALYST should undergo appropriate monitoring for growth and development. [see Use in Specific Populations (8.1) ] Deficiency of Interleukin-1 Receptor Antagonist (DIRA) Safety and effectiveness in pediatric patients with DIRA weighing 10 kg or more have been established [see Adverse Reactions (6.1) and Clinical Studies (14.2) ]. Safety and effectiveness of ARCALYST have not been established in pediatric patients weighing less than 10 kg for maintenance of remission of DIRA.

🧓 Geriatric Use 99 words ▾

8.5Geriatric Use In the placebo-controlled clinical studies, 78 patients randomized to treatment with ARCALYST were ≥ 65 years of age, and 6 were ≥ 75 years of age. In the CAPS clinical trial, efficacy, safety and tolerability were generally similar in elderly patients as compared to younger adults; however, only ten patients ≥ 65 years old participated in the trial. In an open-label extension study of CAPS, a 71-year-old woman developed bacterial meningitis and died [see Adverse Reactions (6.1) ] .

Age did not appear to have a significant effect on steady-state trough concentrations in the clinical study.

🆘 Overdosage 124 words ▾

10 OVERDOSAGE There have been no reports of overdose with ARCALYST. Maximum weekly doses of up to 320 mg have been administered subcutaneously for up to approximately 18 months in a small number of patients with CAPS and up to 6 months in patients with an unapproved indication in clinical trials without evidence of dose-limiting toxicities. In addition, ARCALYST given intravenously at doses up to 2000 mg monthly in another patient population for up to six months was tolerated without dose-limiting toxicities.

The maximum amount of ARCALYST that can be safely administered has not been determined. In case of overdose, it is recommended that the patient be monitored for any signs or symptoms of adverse reactions or effects, and appropriate symptomatic treatment instituted immediately.

🧬 Clinical Pharmacology ~3 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Rilonacept is an interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β) cytokine trap. Rilonacept blocks IL-1 signaling by acting as a soluble decoy receptor that binds both IL-1α and IL-1β and prevents its interaction with cell surface receptors. Rilonacept also binds interleukin-1 receptor antagonist (IL-1ra).

The equilibrium dissociation constants for rilonacept binding to IL-1α, IL-1β, and IL-1ra were 1.4 pM, 0.5 pM, and 6.1 pM, respectively. CAPS refers to rare genetic syndromes generally caused by mutations in the NLRP-3 [nucleotide-binding domain, leucine rich family (NLR), pyrin domain containing 3] gene (also known as Cold-Induced Autoinflammatory Syndrome-1 [ CIAS1 ]). CAPS disorders are inherited in an autosomal dominant pattern with male and female offspring equally affected.

Features common to all disorders include fever, urticaria-like rash, arthralgia, myalgia, fatigue, and conjunctivitis. In most cases, inflammation in CAPS is associated with mutations in the NLRP-3 gene, which encodes the protein cryopyrin, an important component of the inflammasome. Cryopyrin regulates the protease caspase-1 and controls the activation of interleukin-1 beta (IL-1β).

Mutations in NLRP-3 result in an overactive inflammasome, resulting in excessive release of activated IL-1β that drives inflammation. DIRA is an autoinflammatory, autosomal recessive disorder caused by loss of function mutations in the IL1RN gene, which encodes IL-1 receptor antagonist (IL-1ra), resulting in unopposed signaling of the proinflammatory cytokines IL-1α and IL-1β through the IL-1 receptor. Interleukin-1 (IL-1) is a key cytokine that mediates the pathophysiology of many inflammatory processes, and it has been implicated as a causative factor in pericarditis.

IL-1α and IL-1β bind to the universally expressed cell surface receptor, IL-1 Receptor type-1, triggering a cascade of inflammatory mediators. Pre-formed IL-1α is released by damaged/inflamed pericardial cells and may contribute to the maintenance and amplification of inflammation via activation of the NLRP3 inflammasome, which then augments the inflammatory response by production of IL-1β in a cascade amplification system.

12.2Pharmacodynamics C-Reactive Protein (CRP) and Serum Amyloid A (SAA) are indicators of inflammatory disease activity that are elevated in patients with CAPS. Elevated SAA has been associated with the development of systemic amyloidosis in patients with CAPS. Compared to placebo, treatment with ARCALYST resulted in sustained reductions from baseline in mean serum CRP and SAA to normal levels during the clinical trial.

ARCALYST also normalized mean SAA from elevated levels. CRP is also an indicator of inflammation in DIRA. Maintenance of CRP reduction was observed in a clinical trial of pediatric patients with DIRA [see Clinical Studies (14.2) ] .

CRP is also a recognized indicator of inflammation in pericarditis. Treatment with rilonacept was observed in a clinical trial with RP to be associated with resolution of acute pericarditis episodes, including rapid and sustained reduction in CRP, with a median time to normalization of 7 days [see Clinical Studies (14.3) ].

12.3Pharmacokinetics The average trough levels of rilonacept were approximately 24 mcg/mL at steady state following weekly subcutaneous doses of 160 mg for up to 48 weeks in patients with CAPS. The steady state appeared to be reached by 6 weeks. The average trough levels of rilonacept were approximately 23 mcg/mL at steady state, and the circulation half-life in vivo was approximately 7 days following a 320 mg loading dose and weekly subcutaneous doses of 160 mg for up to 36 weeks in patients with RP.

Steady state appeared to be reached by approximately 2 weeks. No pharmacokinetic data are available in patients with hepatic or renal impairment. No specific study was conducted to evaluate the effect of age, gender, or body weight on rilonacept exposure.

Based o… [Excerpted — this section continues on DailyMed.]

🧬 Mechanism of Action ~1 min read ▾

12.1Mechanism of Action Rilonacept is an interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β) cytokine trap. Rilonacept blocks IL-1 signaling by acting as a soluble decoy receptor that binds both IL-1α and IL-1β and prevents its interaction with cell surface receptors. Rilonacept also binds interleukin-1 receptor antagonist (IL-1ra).

The equilibrium dissociation constants for rilonacept binding to IL-1α, IL-1β, and IL-1ra were 1.4 pM, 0.5 pM, and 6.1 pM, respectively. CAPS refers to rare genetic syndromes generally caused by mutations in the NLRP-3 [nucleotide-binding domain, leucine rich family (NLR), pyrin domain containing 3] gene (also known as Cold-Induced Autoinflammatory Syndrome-1 [ CIAS1 ]). CAPS disorders are inherited in an autosomal dominant pattern with male and female offspring equally affected.

Features common to all disorders include fever, urticaria-like rash, arthralgia, myalgia, fatigue, and conjunctivitis. In most cases, inflammation in CAPS is associated with mutations in the NLRP-3 gene, which encodes the protein cryopyrin, an important component of the inflammasome. Cryopyrin regulates the protease caspase-1 and controls the activation of interleukin-1 beta (IL-1β).

Mutations in NLRP-3 result in an overactive inflammasome, resulting in excessive release of activated IL-1β that drives inflammation. DIRA is an autoinflammatory, autosomal recessive disorder caused by loss of function mutations in the IL1RN gene, which encodes IL-1 receptor antagonist (IL-1ra), resulting in unopposed signaling of the proinflammatory cytokines IL-1α and IL-1β through the IL-1 receptor. Interleukin-1 (IL-1) is a key cytokine that mediates the pathophysiology of many inflammatory processes, and it has been implicated as a causative factor in pericarditis.

IL-1α and IL-1β bind to the universally expressed cell surface receptor, IL-1 Receptor type-1, triggering a cascade of inflammatory mediators. Pre-formed IL-1α is released by damaged/inflamed pericardial cells and may contribute to the maintenance and amplification of inflammation via activation of the NLRP3 inflammasome, which then augments the inflammatory response by production of IL-1β in a cascade amplification system.

📦 How Supplied / Storage and Handling 89 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING ARCALYST (rilonacept) for injection is supplied as a sterile, white to off-white, preservative-free, lyophilized powder in single-dose vials. Each 220 mg vial of ARCALYST is supplied in a carton containing one vial (NDC 73604-914-01) or four vials (NDC 73604-914-04). Store refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light.

Do not use beyond the date stamped on the label. After reconstitution, ARCALYST may be kept at room temperature, protected from light [see Dosage and Administration (2.5) ].

📦 Storage and Handling 45 words ▾

Store refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light. Do not use beyond the date stamped on the label. After reconstitution, ARCALYST may be kept at room temperature, protected from light [see Dosage and Administration (2.5) ].

📋 Description 166 words ▾

11 DESCRIPTION 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. Rilonacept has a molecular weight of approximately 251 kDa. Rilonacept is expressed in recombinant Chinese hamster ovary (CHO) cells.

ARCALYST is supplied in single-dose vials containing a sterile, white to off-white lyophilized powder. Each vial of ARCALYST is to be reconstituted with 2.3 mL of Sterile Water for Injection, USP. A volume of up to 2 mL can be withdrawn, which is designed to deliver 160 mg for subcutaneous administration only.

The resulting solution is viscous, clear, colorless to pale yellow, and essentially free from particulates. Each vial contains 220 mg rilonacept. After reconstitution, each vial contains rilonacept (80 mg/mL), glycine (10 mg/mL), histidine (46 mM), L-arginine (50 mM), polyethylene glycol 3350 (30 mg/mL), and sucrose (20 mg/mL) at a pH of 6.5.

No preservatives are present.

💬 Information for Patients ~2 min read ▾

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Patient Information and Instructions for Use). Assessment of Patient's or Caregiver's Administration of ARCALYST : The first injection of ARCALYST should be performed under the supervision of a qualified healthcare professional. If a patient or caregiver is to administer ARCALYST, instruct them on aseptic reconstitution of the lyophilized product and injection technique.

The ability to inject subcutaneously should be assessed to ensure proper administration of ARCALYST, including rotation of injection sites. ( See Patient Information Leaflet for ARCALYST ® ). ARCALYST should be reconstituted with preservative-free Sterile Water for Injection to be provided by the pharmacy.

If the total volume of dose needed is greater than 2 mL, provide instruction about how to divide the total dose and how to administer the 2 injections. Remind patients to discard vials with unused product. A sharps disposal container should be used for disposal of vials, needles and syringes.

Instruct patients or caregivers in proper vial, syringe, and needle disposal, and they should be cautioned against reuse of these items [see Dosage and Administration (2.5) ] . Injection-site Reactions : Explain to patients that almost half of the patients in the clinical trials experienced a reaction at the injection site. Injection-site reactions may include pain, erythema, swelling, pruritus, bruising, mass, inflammation, dermatitis, edema, urticaria, vesicles, warmth, and hemorrhage.

Caution patients to avoid injecting into an area that is already swollen or red. Any persistent reaction should be brought to the attention of the prescribing physician [see Adverse Reactions (6.1) ] . Infections : Caution patients that ARCALYST has been associated with serious, life-threatening infections, and not to initiate treatment with ARCALYST if they have a chronic or active infection.

Advise patients to contact their healthcare professional immediately if they develop an infection after starting ARCALYST. Treatment with ARCALYST should be discontinued if a patient develops a serious infection. Advise patients not to take any IL-1 blocking drug, including ARCALYST, if they are also taking a drug that blocks TNF such as etanercept, infliximab, or adalimumab.

Use of ARCALYST with other IL-1 blocking agents, such as anakinra, is not recommended [see Warnings and Precautions (5.1) ] . Vaccinations : Prior to initiation of therapy with ARCALYST, review the vaccination history with adult and pediatric patients, parent(s), and/or caregiver relative to current medical guidelines for vaccine use, including taking into account the potential of increased risk of infection during treatment with ARCALYST [see Warnings and Precautions (5.5) ] .

🧬 Pharmacokinetics ~1 min read ▾

12.3Pharmacokinetics The average trough levels of rilonacept were approximately 24 mcg/mL at steady state following weekly subcutaneous doses of 160 mg for up to 48 weeks in patients with CAPS. The steady state appeared to be reached by 6 weeks. The average trough levels of rilonacept were approximately 23 mcg/mL at steady state, and the circulation half-life in vivo was approximately 7 days following a 320 mg loading dose and weekly subcutaneous doses of 160 mg for up to 36 weeks in patients with RP.

Steady state appeared to be reached by approximately 2 weeks. No pharmacokinetic data are available in patients with hepatic or renal impairment. No specific study was conducted to evaluate the effect of age, gender, or body weight on rilonacept exposure.

Based on limited data obtained from the Phase 3 study RHAPSODY, steady state trough concentrations were similar between male and female patients. Age (26 to78 years) and body weight (50 to120 kg) did not appear to have a meaningful effect on trough rilonacept concentrations. The effect of race has not been assessed because of low numbers of non-Caucasian patients in the CAPS and RP programs, reflecting the epidemiology of these diseases.

In pediatric patients with DIRA (3 to 6 years of age and body weight 12.7 to 19.9 kg) who received weekly subcutaneous doses of 4.4 mg/kg of ARCALYST, the average steady-state trough levels ranged from 63.5 to 74.0 mg/mL during the period of 6 to 24 months from the start of treatment with ARCALYST.

🧬 Pharmacodynamics 152 words ▾

12.2Pharmacodynamics C-Reactive Protein (CRP) and Serum Amyloid A (SAA) are indicators of inflammatory disease activity that are elevated in patients with CAPS. Elevated SAA has been associated with the development of systemic amyloidosis in patients with CAPS. Compared to placebo, treatment with ARCALYST resulted in sustained reductions from baseline in mean serum CRP and SAA to normal levels during the clinical trial.

ARCALYST also normalized mean SAA from elevated levels. CRP is also an indicator of inflammation in DIRA. Maintenance of CRP reduction was observed in a clinical trial of pediatric patients with DIRA [see Clinical Studies (14.2) ] .

CRP is also a recognized indicator of inflammation in pericarditis. Treatment with rilonacept was observed in a clinical trial with RP to be associated with resolution of acute pericarditis episodes, including rapid and sustained reduction in CRP, with a median time to normalization of 7 days [see Clinical Studies (14.3) ].

🔬 Clinical Studies ~3 min read ▾

14 CLINICAL STUDIES

14.1Cryopyrin-Associated Periodic Syndromes, Familial Cold Autoinflammatory Syndrome and Muckle-Wells Syndrome The safety and efficacy of ARCALYST for the treatment of CAPS was demonstrated in a randomized, double-blind, placebo-controlled study (NCT00288704) with two parts (A and B) conducted sequentially in the same patients with FCAS and MWS. Part A was a 6-week, randomized, double-blind, parallel-group period comparing ARCALYST at a dose of 160 mg weekly after an initial loading dose of 320 mg to placebo. Part B followed immediately after Part A and consisted of a 9-week, patient-blind period during which all patients received ARCALYST 160 mg weekly, followed by a 9-week, double-blind, randomized withdrawal period in which patients were randomly assigned to either remain on ARCALYST 160 mg weekly or to receive placebo.

Patients were then given the option to enroll in a 24-week, open-label treatment extension phase in which all patients were treated with ARCALYST 160 mg weekly. Using a daily diary questionnaire, patients rated the following five signs and symptoms of CAPS: joint pain, rash, feeling of fever/chills, eye redness/pain, and fatigue, each on a scale of 0 (none, no severity) to 10 (very severe). The study evaluated the mean symptom score using the change from baseline to the end of treatment.

The changes in mean symptom scores for the randomized parallel-group period (Part A) and the randomized withdrawal period (Part B) of the study are shown in Table 2. ARCALYST-treated patients had a larger reduction in the mean symptom score in Part A compared to placebo-treated patients. In Part B, mean symptom scores increased more in patients withdrawn to placebo compared to patients who remained on ARCALYST.

Table 2: Mean Symptom Scores Part A Placebo (n=24) ARCALYST (n=23) Part B Placebo (n=23) ARCALYST (n=22) Pre-treatment Baseline Period (Weeks -3 to 0) 2.4

3.1Active ARCALYST Baseline Period (Weeks 13 to 15) 0.2

0.3Endpoint Period (Weeks 4 to 6) 2.1

0.5Endpoint Period (Weeks 22 to 24) 1.2

0.4LS Differences are adjusted using an analysis of covariance model with terms for treatment and Part A baseline. Mean Change from Baseline to Endpoint -0.5 -2.4 LS Mean Change from Baseline to Endpoint 0.9 0.1 95% confidence interval for difference between treatment groups (-2.4, -1.3) A confidence interval lying entirely below zero indicates a statistical difference favoring ARCALYST versus placebo. 95% confidence interval for difference between treatment groups (-1.3, -0.4) Daily mean symptom scores over time for Part A are shown in Figure 1.

Figure 1: Group Mean Daily Symptom Scores by Treatment Group in Part A and Single-blind ARCALYST Treatment Phase from Week -3 to Week 15 Improvement in symptom scores was noted within several days of initiation of ARCALYST therapy in most patients. In Part A, patients treated with ARCALYST experienced more improvement in each of the five components of the composite endpoint (joint pain, rash, feeling of fever/chills, eye redness/pain, and fatigue) than placebo-treated patients. In Part A, a higher proportion of patients in the ARCALYST group experienced improvement from baseline in the composite score by at least 30% (96% vs.

29% of patients), by at least 50% (87% vs. 8%) and by at least 75% (70% vs. 0%) compared to the placebo group.

Serum Amyloid A (SAA) and C-Reactive Protein (CRP) levels are acute phase reactants that are typically elevated in patients with CAPS with active disease. During Part A, mean levels of CRP decreased versus baseline for the ARCALYST treated patients, while there was no change for those on placebo (Table 3). ARCALYST also led to a decrease in SAA versus baseline to levels within the normal range.

Table 3. Mean Serum Amyloid A and C-Reactive Protein Levels Over Time in Part A Part A ARCALYST Placebo SAA (normal range: 0.7 – 6.4 mg/L) (n=22) (n=24) Pre-treatment Baseline 60 110 Week 6 4 110 CRP (normal range: 0.0 – 8.4 mg/L) (n= 21) (n=24) P… [Excerpted — this section continues on DailyMed.]

🧪 Nonclinical Toxicology 52 words ▾

13 NONCLINICAL TOXICOLOGY

13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term animal studies have not been performed to evaluate the carcinogenic potential of rilonacept. A murine analog of rilonacept had no effects on fertility and reproductive performance in male and female mice at subcutaneous doses up to 200 mg/kg three times per week.

📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 49 words ▾

13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term animal studies have not been performed to evaluate the carcinogenic potential of rilonacept. A murine analog of rilonacept had no effects on fertility and reproductive performance in male and female mice at subcutaneous doses up to 200 mg/kg three times per week.

📄 Patient Package Insert ~3 min read ▾

This Patient Information has been approved by the U.S. Food and Drug Administration. Revised: October 2025 Patient Information ARCALYST ® (ARK-a-list) (rilonacept) For Injection For Subcutaneous Use Read this Patient Information before you or your child start taking ARCALYST and each time you or your child get a refill.

There may be new information. This Patient Information leaflet does not take the place of talking with the healthcare provider about your or your child's medical condition or treatment. What is ARCALYST?

ARCALYST is a prescription medicine called an interleukin-1 (IL-1) blocker. ARCALYST is used to treat adults and children 12 years and older with Cryopyrin-Associated Periodic Syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome (FCAS), and Muckle-Wells Syndrome (MWS). ARCALYST is used to maintain control of symptoms of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in adults and children weighing at least 22 pounds (10 kg).

ARCALYST is used to treat Recurrent Pericarditis (RP) and reduce the risk of recurrence in adults and children 12 years and older. It is not known if ARCALYST is safe and effective in children under 12 years of age. It is not known if ARCALYST is safe and effective in children with DIRA weighing less than 22 pounds (10 kg).

What is the most important information I should know about ARCALYST? ARCALYST can affect your or your child's immune system. ARCALYST can lower the ability of your or your child's immune system to fight infections.

Serious infections, including life-threatening infections and death, have happened in people taking ARCALYST. Taking ARCALYST can make you or your child more likely to get infections, including life-threatening serious infections, or may make any infection that you or your child have worse. You or your child should not begin treatment with ARCALYST if you or your child have an infection or have infections that keep coming back (chronic infection).

After starting ARCALYST , if you or your child get an infection, any sign of an infection, including a fever, cough, flu-like symptoms, or have any open sores on your body, call the healthcare provider right away. Treatment with ARCALYST should be stopped if you or your child get a serious infection. You or your child should not take medicines that block tumor necrosis factor (TNF), such as Enbrel ® (etanercept), Humira ® (adalimumab), or Remicade ® (infliximab), while you or your child are taking ARCALYST.

You or your child should also not take other medicines that block interleukin-1 (IL-1), such as Kineret ® (anakinra), while taking ARCALYST. Taking ARCALYST with any of these medicines may increase your or your child's risk of getting a serious infection. Before starting treatment with ARCALYST , tell the healthcare provider if you or your child: think you have an infection. are being treated for an infection. have signs of an infection, such as fever, cough, or flu-like symptoms. have any open sores on your body. have a history of infections that keep coming back. have asthma.

People with asthma may have an increased risk of infection. have diabetes or an immune system problem. People with these problems have a higher chance for infections. have tuberculosis (TB), or if you have been in close contact with someone who has had tuberculosis. have or have had HIV, hepatitis B, or hepatitis C. take other medicines that affect your immune system. Before you or your child begin treatment with ARCALYST, talk with the healthcare provider about your or your child's vaccine history.

Ask the healthcare provider whether you or your child should receive any vaccines, including the pneumonia vaccine and flu vaccine, before you or your child begin treatment with ARCALYST. What should I tell my or my child's healthcare provider before taking ARCALYST? ARCALYST may not be right for you or your child.

Before taking ARCALYST, tell your or your child's healthcare provider about all medical conditions, including… [Excerpted — this section continues on DailyMed.]

📖 Instructions for Use ~3 min read ▾

Instructions for Use ARCALYST ® (ARK-a-list) (rilonacept) For Injection For Subcutaneous Use It is important that you read, understand, and follow these instructions before you or your child start using ARCALYST so that you prepare and inject the medicine the right way. Do not try to inject ARCALYST until you have been shown the right way to give the injections by your or your child's healthcare provider. How do I prepare and give an ARCALYST injection?

Step 1: Setting up for an injection Choose a table or other flat area to set up the supplies for your injection. Be sure the area is clean or clean it with an antiseptic or soap and water. Wash your hands well with soap and water about 20 seconds, and dry with a clean towel.

Put the following supplies on the cleaned area for each injection (see Figure A ): Figure A Supplies needed to give your ARCALYST injection: 1 vial of ARCALYST (powder for mixing) Additional supplies needed (available from the pharmacy) : 1 vial of preservative-free Sterile Water for Injection, USP 2 sterile, 3-milliliter (mL) disposable syringes with markings at each 0.1 mL (see Figure B ): 1 syringe for mixing ARCALYST 1 syringe for injection Figure B 2 sterile disposable needles (18-gauge, 1-inch or 1½-inch) and 1 sterile disposable needle (26-gauge, ½-inch) with needle covers 1 18-gauge needle for transferring the Sterile Water for Injection, USP, to the ARCALYST vial 1 18-gauge needle for withdrawing the mixed solution 1 26-gauge needle for injection 4 alcohol wipes 1 gauze pad 1 sharps disposal container for throwing away (disposing of) used needles, syringes, and vials Note : Do not use Sterile Water for Injection, USP, syringes or needles other than those provided by your pharmacy.

Contact your pharmacy if you need replacement syringes or needles. Do not touch the needles or the rubber stoppers on the vials with your hands. If you touch the rubber stopper, clean it with a new alcohol wipe.

If you touch a needle or the needle touches any surface, throw away the entire syringe in the sharps disposal container and use a new syringe. Do not reuse needles or syringes. To protect yourself and others from possible needlesticks, it is very important to throw away each syringe, with the needle attached, in the sharps disposal container right after use.

Step 2: Preparing the vials 1. Check the expiration date on the carton or on the vial of ARCALYST. Do not use the vial if the expiration date has passed.

Contact your pharmacy if the expiration date has passed. 2. Check the expiration date on the vial of Sterile Water for Injection, USP.

Do not use the vial if the expiration date has passed. Contact your pharmacy for assistance. 3.

Remove the protective plastic caps from both vials. 4. Clean the top of each vial with an alcohol wipe.

Use 1 wipe for each vial and wipe in 1 direction around the top of the vial (see Figure C ). Figure C 5. Check the expiration date on the needle.

Do not use the needle if the expiration date has passed. Contact your pharmacy if the expiration date has passed. 6.

Open the wrapper that contains 1 of the 18-gauge needles by pulling apart the tabs and set it aside for later use. Do not remove the needle cover. This needle will be used to mix the water with ARCALYST powder in the vial.

7. Check the expiration date on the syringe. Do not use the syringe if the expiration date has passed.

Contact your pharmacy if the expiration date has passed. 8. Open the wrapper that contains the syringe by pulling apart the tabs (see Figure D ).

9. Hold the barrel of the syringe with one hand and use your other hand to twist the 18-gauge needle with the cover onto the tip of the syringe until it fits firmly (see Figure E ). Figure D Figure E 10.

Hold the syringe upright at eye level. With the needle cover still on the 18-gauge needle, pull back the plunger to the 2.3 mL mark to fill the syringe with air (see Figure F ). Figure F 11.

Hold the syringe in one hand and use the other hand to pull the needl… [Excerpted — this section continues on DailyMed.]

📄 Recent Major Changes 1 words ▾

None.

📄 Package Label / Principal Display Panel 123 words ▾

PRINCIPAL DISPLAY PANEL - 220 mg Vial Carton - NDC 73604-914-04 NDC 73604-914-04 Arcalyst ® (rilonacept) For Injection 220 mg per vial For subcutaneous use only Must be reconstituted Store refrigerated at 2°C to 8°C (36°F to 46°F) until use. Protect from light. Rx ONLY KINIKSA Contents: four (4) single-dose vials PRINCIPAL DISPLAY PANEL - 220 mg Vial Carton - NDC 73604-914-04

PRINCIPAL DISPLAY PANEL - 220 mg Vial Carton - NDC 73604-914-01 NDC 73604-914-01 Arcalyst ® (rilonacept) For Injection 220 mg per vial For subcutaneous use only. Must be reconstituted. Store refrigerated at 2°C to 8°C (36°F to 46°F) until use. Protect from light. Rx ONLY KINIKSA Contents: one single-dose vial PRINCIPAL DISPLAY PANEL - 220 mg Vial Carton - NDC 73604-914-01

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

Medicaid utilization & spend

📍 This exact package only: Medicaid data is reported per full 11-digit NDC — labeler, product and pack size — so every number here is for this package alone, not the drug overall. Other pack sizes report separately.
💊 Pharmacy benefit only: These are Medicaid outpatient pharmacy claims, billed by NDC. They exclude the medical benefit — clinic- or hospital-administered drugs billed under HCPCS J-codes — so drugs used mostly that way (e.g. Avastin, Lucentis, Keytruda) can look low or missing here. That’s expected, not an error.
📅 Q1 2025 – Q1 2026 · 5 quarters of data
ⓘ The newest quarter is usually incomplete when first published; states restate recent quarters in later CMS releases, so the latest figures typically revise upward. State coverage-policy changes can also shift quarter-to-quarter totals.
Prescriptions last 4 qtrs
2.3K
Units reimbursed last 4 qtrs
9.2K
Gross reimbursed last 4 qtrs
$55.4M
Avg / prescription
$24,342.71
Avg / unit
$6,013.03
Latest quarter Q1 2026
625Rx
Fee-for-service vs managed care ⓘ
52% FFS 48% MCO
Fee-for-service · 1,181 Rx Managed care · 1,095 Rx
State Medicaid map
Alaska: no data reported AK Maine: 44 units · 3.2 per 100k residents ME Washington: 100 units · 1.3 per 100k residents WA Idaho: no data reported ID Montana: no data reported MT North Dakota: no data reported ND Minnesota: no data reported MN Wisconsin: 60 units · 1.0 per 100k residents WI Michigan: 296 units · 2.9 per 100k residents MI New York: 2,040 units · 10.4 per 100k residents NY Vermont: no data reported VT New Hampshire: no data reported NH Oregon: no data reported OR Nevada: no data reported NV Wyoming: no data reported WY South Dakota: no data reported SD Iowa: no data reported IA Illinois: 288 units · 2.3 per 100k residents IL Indiana: 44 units · 0.6 per 100k residents IN Ohio: 965 units · 8.2 per 100k residents OH Pennsylvania: 516 units · 4.0 per 100k residents PA New Jersey: 260 units · 2.8 per 100k residents NJ Massachusetts: 438 units · 6.3 per 100k residents MA California: 1,564 units · 4.0 per 100k residents CA Utah: 44 units · 1.3 per 100k residents UT Colorado: 80 units · 1.4 per 100k residents CO Nebraska: no data reported NE Missouri: 260 units · 4.2 per 100k residents MO Kentucky: 48 units · 1.1 per 100k residents KY West Virginia: no data reported WV Virginia: 175 units · 2.0 per 100k residents VA Maryland: 184 units · 3.0 per 100k residents MD Connecticut: 236 units · 6.5 per 100k residents CT Rhode Island: no data reported RI Arizona: 220 units · 3.0 per 100k residents AZ New Mexico: no data reported NM Kansas: no data reported KS Arkansas: no data reported AR Tennessee: 228 units · 3.2 per 100k residents TN North Carolina: 324 units · 3.0 per 100k residents NC South Carolina: 48 units · 0.9 per 100k residents SC Delaware: no data reported DE Oklahoma: no data reported OK Louisiana: 276 units · 6.0 per 100k residents LA Mississippi: no data reported MS Alabama: no data reported AL Georgia: no data reported GA D.C.: no data reported DC Hawaii: no data reported HI Texas: 248 units · 0.8 per 100k residents TX Florida: 228 units · 1.0 per 100k residents FL
Units reimbursed · per 100k residents
0.610.4
gray = no data reported ⓘ
Colors are per 100,000 residents, so big states don’t automatically dominate. Tap or hover a state for its actual totals.
Tap or hover a state
…for its Medicaid breakdown
🏆 Top states by units · per 100k residents
1 New York 10.4 /100k
2 Ohio 8.2 /100k
3 Connecticut 6.5 /100k
4 Massachusetts 6.3 /100k
5 Louisiana 6.0 /100k
6 Missouri 4.2 /100k
7 California 4.0 /100k
8 Pennsylvania 4.0 /100k
National units — by quarter
💵 About the dollar figures: “reimbursed” is what Medicaid paid pharmacies before confidential manufacturer rebates, so the program’s real net cost is lower than these numbers. Fee-for-service and managed-care claims are combined unless split above. Source: CMS State Drug Utilization Data; per-100k rates use 2023 Census population estimates.

Medicaid utilization by pack size

Medicaid (SDUD) totals over the four most recent reported quarters for every package size of this drug — handy when a specific package (e.g. a starter/titration pack) carries little or no Medicaid volume on its own.
4 vials this page73604-0914-04 2,276 Rx · $55,404,016
1 vial73604-0914-01 No Medicaid data
Drug total (last 4 qtrs): 2,276 Rx · 9,214 units · $55,404,016 gross reimbursed
Tap a pack size to open its page. Source: CMS State Drug Utilization Data, last 4 quarters.

Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Arcalyst — the program that covers self-administered drugs. 1 manufacturer.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Arcalyst. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$57.03M
Claims incl. refills
2.2K
Beneficiaries
849
Spend / beneficiary
$67,170.94
Spend / claim
$25,573.15
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope.
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) ✓ Available
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The form printed on the packaging and shown on DailyMed is the one the FDA registered. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero and the dashes are dropped. The Identity section at the top of this page lists each form of this code.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Kiniksa Pharmaceuticals (UK), Ltd.. Listing status can change — the directory data on this page refreshes weekly.
Does this product come in other package sizes?
Yes — the FDA directory lists 1 other package presentation of this same product, including 1 vial (73604-0914-01). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
Kiniksa Pharmaceuticals (UK), Ltd. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.
← 73603-0000-00 · PMS4PMS 73606-0010-01 · Apellis →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.