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Korsuva difelikefalin 50 ug/mL Injection, Solution, 12 vials — NDC 59353-0065-12 package photo

Korsuva difelikefalin 50 ug/mL Injection, Solution, 12 vials

by Vifor (International), Inc. · 12 VIAL, SINGLE-USE in 1 TRAY (59353-065-12) / 1.3 mL in 1 VIAL, SINGLE-USE (59353-065-01)
NDC 59353-0065-12
🏷️ FDA NDC (as labeled) 59353-065-12 billing pads the product segment with a zero
Rx only Brand On market Non-controlled
🗂️ Data synced Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

🆔 Identity & classification

FDA NDC (as labeled) 59353-065-12
Product NDC 59353-065
11-digit billing NDC 59353006512
NCPDP billing unit ML — per mL (volume)
RxCUI 2569094, 2569100
UNII 0P70AR5BYB
Application # NDA214916
SPL Set ID 0c7b81f2-0fd3-47cb-8b0f-185e07f19c87
Established class (EPC) Kappa Opioid Receptor Agonist
Mechanism of action Opioid kappa Receptor Agonists
DEA schedule Non-controlled
Marketing category NDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2021-11-01
Route INTRAVENOUS
Dosage form INJECTION, SOLUTION
Substance DIFELIKEFALIN ACETATE
GPI-14 99690020102020
GPI class Korsuva
GCN Seq No 082600
GCN 50074
HICL code 047561
Ingredient (HICL) Difelikefalin Acetate
HIC1 code L
Therapeutic class — broad (HIC1) Skin/Subcutaneous Tissue
HIC2 code L1
Therapeutic class — intermediate (HIC2) Drugs To Treat Specific Top Diseases (Systemic)
HIC3 code L1H
Therapeutic class — specific (HIC3) Antipruritics, Systemic
AHFS code 84:08.00.00
AHFS class Antipruritics And Local Anesthetics
FDB label name KORSUVA 65 MCG/1.3 ML VIAL
FDB brand name Korsuva
Legend status F — Federal legend — prescription drug or device
Why two NDCs? The FDA registers this code as 59353-065-12 — 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 → 59353-0065-12. 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 Kappa Opioid Receptor Agonist class.

Pharmacologic class Kappa Opioid Receptor Agonist
Drug family (ATC) Other therapeutic products
How it works Opioid kappa Receptor Agonists
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.

🏭 Manufacturer & labeler

LabelerVifor (International), Inc.
Application holderVIFOR (INTERNATIONAL) INC
FDA applicationNDA214916 (NDA)
Labeler code59353
First marketedNov 2021
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.

🩺 Clinical

Label name KORSUVA 65 MCG/1.3 ML VIAL Ingredient Difelikefalin Acetate
📖 What it is MedlinePlus · NLM

Difelikefalin injection is used to treat itching in people with chronic kidney disease who are on hemodialysis (medical treatment to remove waste from the blood when the kidneys are not working properly). Difelikefalin is in a class of medications called kappa opioid receptor agonists. It works by changing the way your nerves respond to itching.

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Moderate-to-severe itching is actually a very common and often overlooked problem for people on hemodialysis. It's related to chronic kidney disease itself — not just dry skin. Kor...
  • What exactly is Korsuva treating — why do I itch so much with kidney disease?
  • You don't have to do anything at home. Korsuva is given as a small injection into the dialysis line by your care team at the end of every hemodialysis session. It takes just a mome...
  • How and when do I get this medication — do I have to take it at home?
📖 Read our full Difelikefalin Injection guide →
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.

🧪 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.

A current SPL was checked, but it does not contain a structured or narrative inactive-ingredient list for this product. This does not mean the product has no inactive ingredients.
Where does this data come from?
Source: official FDA Structured Product Labeling (SPL) via DailyMed and the openFDA label index. Structured IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.

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.

💲 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 $1.24 $19.34 / 15.6 ml
Medicare drug plans payPart D · quarterly No Part D plan price is available for this NDC in our data.
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.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Korsuva 50 ug/mLthis 59353-0065-12 Vifor 12 vials — — FDA listed —
About this product: this is the brand-name version. We did not find an FDA-approved generic match for this exact strength, form and route.
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 & generic status

🏛️
2021
First FDA approval
Aug 2021
📍
2026
Currently FDA-listed
5 years listed
🛡️
2032
Latest patent/protection listed
not a guaranteed launch date
🔒No FDA-approved generic found

We did not find an FDA-approved generic match for this exact strength, form and route. Patent/protection dates below may affect future generic timing.

🛡️ Latest patent/protection date listed: FDA patent/protection data lists protections through Nov 2032. This may affect when a full generic version becomes widely available, but it is not a guaranteed launch date.
📅 FDA approved Aug 23, 2021 RLD RS ⏳ ~6.1 yr to latest listed protection

Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.

Patents & exclusivity — FDA Orange Book
US 10793596 — drug substance (U-3204)
US 10138270 — method of use (U-3204)
US 10017536 — drug substance (U-3204)
US 9359399 — method of use (U-3204)
US 9334305 — method of use (U-3204)
US 8536131 — drug substance (U-3204)
US 8486894 — method of use (U-3204)
US 8236766 — method of use (U-3204)
US 8217007 — method of use (U-3204)
US 7727963 — drug substance (U-3204)
US 7713937 — drug substance (U-3204)
US 7402564 — drug substance (U-3204)
Exclusivity NCE
2021 2023 2025 2027 2029 2031 2033
Today
LOE
Substance patent Formulation patent Method-of-use patent Exclusivity Pediatric +6mo
🏛️FDA exclusivity
FDA-granted marketing protection. It’s separate from patents and may be shorter than patent protection.
🧪Product / substance patents
Patents covering the active ingredient, product, formulation, or related drug features.
🎯Method-of-use patents
Patents covering specific approved uses. These can sometimes be carved out with a “skinny label,” but not always.
🛈 What do these terms mean?
Patent
Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
Substance patent
Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
Formulation (product) patent
Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
Method-of-use patent
A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
Skinny label
A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
Exclusivity
FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
Paragraph IV
A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
RLD / RS
Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
TE / AB rating
FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
LOE (loss of exclusivity)
The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.

Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.

Listed patents (12)
PatentTypeUse codeExpires
US 10793596 ↗ Drug substance U-3204 Nov 12, 2027
US 10138270 ↗ Method of use U-3204 Nov 12, 2027
US 10017536 ↗ Drug substance U-3204 Nov 12, 2027
US 9359399 ↗ Method of use U-3204 Nov 12, 2027
US 9334305 ↗ Method of use U-3204 Nov 12, 2027
US 8536131 ↗ Drug substance U-3204 Nov 12, 2027
US 8486894 ↗ Method of use U-3204 Nov 12, 2027
US 8236766 ↗ Method of use U-3204 Nov 12, 2027
US 8217007 ↗ Method of use U-3204 Nov 12, 2027
US 7727963 ↗ Drug substance U-3204 Nov 12, 2027
US 7713937 ↗ Drug substance U-3204 Nov 12, 2027
US 7402564 ↗ Drug substance U-3204 Nov 12, 2032
FDA exclusivity
CodeWhat it grantsExpires
NCENew Chemical Entity (5-year)Aug 23, 2026
Common questions
Is there a generic version of KORSUVA 65 MCG/1.3 ML VIAL?
No FDA-approved generic equivalent is currently listed in the FDA Orange Book for KORSUVA 65 MCG/1.3 ML VIAL. Based on the patents and exclusivity currently listed, the Orange Book estimate is that full-label generic entry may be delayed until Nov 2032 — an estimate, not a guaranteed launch date.
The FDA approved a generic — why can’t I get it at my pharmacy yet?
FDA approval and pharmacy availability are two different things. The FDA can approve a generic years before it actually reaches pharmacies, because the brand company may still hold patents or have a settlement that delays the launch. A manufacturer also has to choose to make and sell it, and have supply ready. So a drug can be “FDA-approved generic exists” and still be brand-only at the counter today.
Why do different websites show different generic release dates?
Generic availability is not based on one single date. Some sources use the first exclusivity expiration, some use the last product patent, and others use the latest method-of-use patent. Patent challenges, settlements, licenses, and label carve-outs can also change the real-world launch date. This page shows the underlying Orange Book dates so you can see why estimates may differ.
What does “FDA listed” mean?
It means the product appears in the FDA’s official NDC directory. That’s a good sign a product exists and is intended for the U.S. market, but on its own it does not confirm a pharmacy can fill it today. Where we have recent retail pricing data (NADAC) for a product, we label it “Availability likely” instead.
What does a patent or protection date mean here?
It’s the latest date currently listed in the FDA Orange Book for a patent or exclusivity on the brand product. It can affect when a full generic version becomes widely available — but it is not a guaranteed generic launch date. Generics sometimes arrive earlier (through a settlement or patent challenge) or later (a manufacturer still has to make and sell one).
What does “current Orange Book estimate” mean?
It means we are using the latest patent and exclusivity dates currently listed in the FDA Orange Book. It is not a guaranteed launch date.
Can a generic come out before the last patent expires?
Sometimes. A generic company may challenge a patent, settle with the brand manufacturer, receive a license, or obtain approval with a narrower label that avoids a patented use. In other cases, the last listed protection may delay full-label generic competition.
Can a generic come out after the listed dates?
Yes. Even after patents or exclusivity expire, a generic still needs FDA approval and a manufacturer must choose to market it. Supply, litigation, business decisions, or regulatory issues can delay actual availability.
What is the difference between patents and exclusivity?
Patents are legal protections usually issued by the U.S. Patent and Trademark Office. FDA exclusivity is marketing protection granted by the FDA. They are separate, and either one can affect generic timing.
Why are there multiple patent dates?
One drug can have several patents covering different things: the active ingredient, a formulation, a manufacturing process, or a specific approved use. That is why a page may show several expiration dates instead of one simple generic date.
Built from FDA Orange Book patent and exclusivity data. Dates are refreshed from public FDA data when available; the marker is max(latest patent expiry, latest exclusivity expiry). Paragraph-IV settlements and first-filer 180-day exclusivity can shift the real date; a method-of-use patent may allow an earlier skinny-label generic for non-protected indications. Generic launch timing is an estimate, not a guarantee.
Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

🗺️ 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 59353-0065-12, 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 · 4 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
60
Units reimbursed last 4 qtrs
30
Gross reimbursed last 4 qtrs
$37.20
Avg / prescription
$0.62
Avg / unit
$1.2576
Latest quarter Q1 2026
37Rx
Fee-for-service vs managed care ⓘ
100% MCO
Fee-for-service · 0 Rx Managed care · 60 Rx
State Medicaid map
Alaska: no data reported AK Maine: no data reported ME Washington: no data reported WA Idaho: no data reported ID Montana: no data reported MT North Dakota: no data reported ND Minnesota: no data reported MN Wisconsin: no data reported WI Michigan: no data reported MI New York: no data reported 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: no data reported IL Indiana: no data reported IN Ohio: 30 units · 0.3 per 100k residents OH Pennsylvania: no data reported PA New Jersey: no data reported NJ Massachusetts: no data reported MA California: no data reported CA Utah: no data reported UT Colorado: no data reported CO Nebraska: no data reported NE Missouri: no data reported MO Kentucky: no data reported KY West Virginia: no data reported WV Virginia: no data reported VA Maryland: no data reported MD Connecticut: no data reported CT Rhode Island: no data reported RI Arizona: no data reported AZ New Mexico: no data reported NM Kansas: no data reported KS Arkansas: no data reported AR Tennessee: no data reported TN North Carolina: no data reported NC South Carolina: no data reported SC Delaware: no data reported DE Oklahoma: no data reported OK Louisiana: no data reported 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: no data reported TX Florida: no data reported FL
Units reimbursed · per 100k residents
0.30.3
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 Ohio 0.3 /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.

🔬 Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Difelikefalin — the ingredient across all brands.

Top reported reactions

Dizziness45
Somnolence39
Fall35
Death29
Mental Status Changes23
Confusional State19
Nausea18

Reporter sex

0 reports

Serious outcomes

Hospitalization120
Reports over time (by year) — tap or hover for the count & year
2023 2024 2025 2026 124 29
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
59353-0065-12 You're viewing this 12 VIAL, SINGLE-USE in 1 TRAY (59353-065-12) / 1.3 mL in 1 VIAL, SINGLE-USE (59353-065-01) 2021-01-11 Active

🧭 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) — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is 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 ✓ Available
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 FDA registers it as 59353-065-12, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 59353-0065-12, written without dashes as 59353006512. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 59353-0065-12, the first segment (59353) is the labeler code FDA assigned to Vifor (International), Inc.; the middle segment (0065) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (12) identifies this exact package size and type. Together they name one specific package of one specific product.
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 Vifor (International), Inc.. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
Vifor (International), Inc. 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.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage 99 words ▾

1 INDICATIONS AND USAGE KORSUVA is indicated for the treatment of moderate-to-severe pruritus associated with chronic kidney disease (CKD-aP) in adults undergoing hemodialysis (HD). KORSUVA is a kappa opioid receptor agonist indicated for the treatment of moderate-to-severe pruritus associated with chronic kidney disease (CKD-aP) in adults undergoing hemodialysis (HD). ( 1 ) Limitation of Use Korsuva has not been studied in patients on peritoneal dialysis and is not recommended for use in this population.

( 1 ) Limitations of Use KORSUVA has not been studied in patients on peritoneal dialysis and is not recommended for use in this population.

⏱️ Dosage and Administration ~2 min read ▾

2 DOSAGE AND ADMINISTRATION Recommended dosage is 0.5 mcg/kg. ( 2.1 ) Administer by intravenous bolus injection into the venous line of the dialysis circuit at the end of each HD treatment. ( 2.1 ) Do not mix or dilute KORSUVA prior to administration. ( 2.2 ) Administer within 4 hours of syringe preparation. ( 2.3 ) See full prescribing information for additional recommendations on preparation and administration of KORSUVA. ( 2.2 , 2.3 )

2.1Dosage The recommended dosage of KORSUVA is 0.5 mcg/kg administered by intravenous bolus injection into the venous line of the dialysis circuit at the end of each HD treatment [see Dosage and Administration (2.3) ] . If a regularly scheduled HD treatment is missed, resume KORSUVA at the end of the next HD treatment.

2.2Preparation Instructions Do not mix or dilute KORSUVA prior to administration. Inspect KORSUVA for particulate matter and discoloration prior to administration. The solution should be clear and colorless.

Do not use KORSUVA vials if particulate matter or discoloration is observed. KORSUVA is supplied in a single-dose vial. Discard any unused product.

Injection volume to be administered is determined by patient's target dry body weight in kilograms (one patient may use less than the full contents of the vial or use more than one vial). See Table 1 . Table 1.

KORSUVA Injection Volumes Based on Target Dry Body Weight Target Dry Body Weight Range (kg) Injection Volume (mL) Total Injection Volume (mL) = Patient Target Dry Body Weight (kg) x 0.01, rounded to the nearest tenth (0.1 mL). For patient target dry body weight outside of the ranges in Table 1, use this formula. 36 – 44 0.4 45 – 54 0.5 55 – 64 0.6 65 – 74 0.7 75 – 84 0.8 85 – 94 0.9 95 – 104 1 105 – 114 1.1 115 – 124 1.2 125 – 134 1.3 135 – 144 1.4 145 – 154 1.5 155 – 164 1.6 165 – 174 1.7 175 – 184 1.8 185 – 194 1.9 195 – 204 2

2.3Administration Instructions KORSUVA is removed by the dialyzer membrane and must be administered after blood is no longer circulating through the dialyzer. Administer KORSUVA by intravenous bolus injection into the venous line of the dialysis circuit at the end of each HD session. The dose may be given either during or after rinse back of the dialysis circuit.

If the dose is given after rinse back, administer KORSUVA into the venous line followed by at least 10 mL of normal saline flush. If the dose is given during rinse back, no additional normal saline is needed to flush the line. The dose must be administered within 4 hours of the syringe preparation.

Discard any unused product.

💊 Dosage Forms and Strengths 36 words ▾

3 DOSAGE FORMS AND STRENGTHS Injection: 65 mcg/1.3 mL (50 mcg/mL) of difelikefalin as a clear, colorless solution in a single-dose glass vial. Injection : 65 mcg /1.3 mL (50 mcg/mL) of difelikefalin ( 3 )

⛔ Contraindications 4 words ▾

4 CONTRAINDICATIONS None None

⚠️ Warnings and Cautions ~1 min read ▾

5 WARNINGS AND PRECAUTIONS Dizziness, Somnolence, Mental Status Changes, and Gait Disturbances: Dizziness, somnolence, mental status changes, and gait disturbances, including falls, have occurred. Centrally-acting depressant medications, sedating antihistamines, and opioid analgesics should be used with caution during treatment with KORSUVA. ( 5.1 ) Risk of Driving and Operating Machinery: May impair mental or physical abilities.

Advise patients not to drive or operate dangerous machinery until the effect of KORSUVA on a patient's ability to drive or operate machinery is known. ( 5.2 )

5.1Dizziness, Somnolence, Mental Status Changes, and Gait Disturbances Dizziness, somnolence, mental status changes, and gait disturbances, including falls, have occurred in patients taking KORSUVA and may subside over time with continued treatment [see Adverse Reactions (6.1) ] . In Trial 1 and Trial 2, 17.0% of patients randomized to receive KORSUVA reported at least one of these adverse reactions, compared to 12.0% of patients who received placebo. The incidence of somnolence was higher in KORSUVA-treated subjects 65 years of age and older (7.0%) than in KORSUVA-treated subjects less than 65 years of age (2.8%).

Concomitant use of centrally-acting depressant medications, sedating antihistamines and opioid analgesics may increase the likelihood of these adverse reactions and should be used with caution during treatment with KORSUVA.

5.2Risk of Driving and Operating Machinery Dizziness, somnolence, and mental status changes have occurred in patients taking KORSUVA. KORSUVA may impair the mental or physical abilities needed to perform potentially hazardous activities such as driving a car and operating machinery. Advise patients not to drive or operate dangerous machinery until the effect of KORSUVA on a patient's ability to drive or operate machinery is known .

🤒 Adverse Reactions ~3 min read ▾

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Dizziness, Somnolence, Mental Status Changes, and Gait Disturbances [see Warnings and Precautions (5.1) ] The most common adverse reactions (incidence ≥2% and ≥1% higher than placebo) were diarrhea, dizziness, nausea, gait disturbances, including falls, hyperkalemia, headache, somnolence, and mental status change. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Vifor (International) Inc. at 1-844-835-8277 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. A total of 1306 subjects undergoing HD who had moderate-to-severe pruritus were treated with KORSUVA in placebo-controlled and uncontrolled Phase 3 clinical trials. Of these, 711 were treated for at least 6 months and 400 were treated for at least one year.

Two placebo-controlled Phase 3 trials (Trial 1 and Trial 2), in subjects undergoing HD who had moderate-to-severe pruritus were pooled to evaluate the safety of KORSUVA in comparison to placebo up to 12 weeks. In total, 848 subjects were evaluated (424 in KORSUVA group and 424 in placebo group). The mean age of the subjects was 59 years (range 22 to 88 years), and 59% of the subjects were male.

Of the total subjects, 61% were White, 29% were Black or African American, and 5% were Asian. Table 2 summarizes the adverse reactions that occurred at a rate of ≥2% in the KORSUVA group and ≥1% higher than that of the placebo group during the 12-week placebo-controlled period of Trials 1 and 2. The percentage of subjects who discontinued treatment due to any adverse reaction was 2.6% for subjects taking KORSUVA and 0.7% for subjects taking placebo.

The most common adverse reactions (≥0.5% of subjects) leading to discontinuation were dizziness (0.9% for KORSUVA and 0.2% for placebo), mental status change (0.7% and 0.2%, respectively), nausea (0.5% and 0%, respectively), and headache (0.5% and 0%, respectively). The percentage of subjects who developed serious adverse reactions was 4.5% in the KORSUVA group and 2.8% in the placebo group. Table 2: Adverse Reactions in ≥ 2% of KORSUVA-Treated Subjects with Moderate-to-Severe CKD-aP Undergoing HD and ≥ 1% Higher Than Placebo in Trials 1 and 2 Adverse Reactions Placebo (N=424) n (%) KORSUVA (N=424) n (%) Diarrhea 24 (5.7) 38 (9.0) Dizziness 16 (3.8) 29 (6.8) Nausea 19 (4.5) 28 (6.6) Gait Disturbances Gait disturbances includes: preferred terms of falls and gait disturbances 23 (5.4) 28 (6.6) Hyperkalemia 15 (3.5) 20 (4.7) Headache 11 (2.6) 19 (4.5) Somnolence 10 (2.4) 18 (4.2) Mental Status Change Mental Status Change includes: preferred terms of confusional state and mental status change.

6 (1.4) 14 (3.3) Description of Selected Adverse Reactions Gait Disturbances, including Falls Gait disturbances, including falls, were reported in 6.6% of subjects receiving KORSUVA compared to 5.4% of subjects who received placebo. Falls were reported as serious adverse reactions in < 1% of subjects receiving KORSUVA and placebo, with one subject discontinuing KORSUVA due to gait disturbance. Dizziness Dizziness was reported in 6.8% of subjects randomized to KORSUVA compared to 3.8% of subjects who received placebo.

Dizziness occurred within the first 3 weeks of treatment and was generally transient. Dizziness was serious in 0.2% of KORSUVA-treated subjects compared to 0% of subjects who received placebo and led to discontinuation in 0.9% of KORSUVA-treated subjects compared to 0.2% of subjects who received placebo. Somnolence Somnolence was reported in 4.2% of subjects randomized to receive KORSUVA compared to 2.4% of subjects who received placebo.

Somnolence occurred within the first 3 weeks…

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS Severe Hepatic Impairment: Not recommended in patients with severe hepatic impairment. ( 8.6 )

8.1Pregnancy Risk Summary The limited human data on use of KORSUVA in pregnant women are not sufficient to evaluate a drug-associated risk for major birth defects or miscarriage. In animal reproduction studies, intravenous injection of difelikefalin to pregnant rats and rabbits during the period of organogenesis at doses 711 and 10 times the maximum recommended human dose (MRHD), respectively, resulted in no adverse effects in either rats or rabbits (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown.

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Data Animal Data In an embryofetal development study, difelikefalin was administered by intravenous injection to pregnant rats at doses of 0.25, 2.5, and 25 mg/kg/day during the period of organogenesis. Difelikefalin was not associated with embryofetal lethality or fetal malformations.

Difelikefalin increased the incidences of skeletal variations (wavy ribs and incompletely ossified ribs) at the dose of 25 mg/kg/day (711 times the MRHD based on AUC comparison). In an embryofetal development study, difelikefalin was administered by intravenous injection to pregnant rabbits at doses of 0.025, 0.05, and 0.1 mg/kg/day during the period of organogenesis. Maternal toxicity evidenced by decreased maternal body weight gain was noted in all dose groups.

Difelikefalin was not associated with embryofetal lethality or fetal malformations at doses up to 0.1 mg/kg/day (10 times the MRHD based on AUC comparison). In a prenatal and postnatal development study, difelikefalin was administered by intravenous injection to pregnant rats at doses of 0.6, 2.5, and 10 mg/kg/day beginning on gestation day 7 and continuing through lactation day 20. Persisting effects on decreased maternal body weight and/or maternal body weight gain as well as food consumption were noted at doses greater than or equal to 2.5 mg/kg/day (68 times the MRHD based on AUC comparison).

No maternal effects were observed at 0.6 mg/kg/day (14 times the MRHD based on AUC comparison). No difelikefalin-related effects on postnatal developmental, neurobehavioral, or reproductive performance of offspring were noted at doses up to 10 mg/kg/day (282 times the MRHD based on AUC comparison).

8.2Lactation Risk Summary There are no data regarding the presence of KORSUVA in human milk or effects on the breastfed infant or on milk production. Studies in rats showed difelikefalin was transferred into the milk in lactating rats. When a drug is present in animal milk, it is likely that the drug will be present in human milk.

The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for KORSUVA and any potential adverse effects on the breastfed child from KORSUVA or from the underlying maternal condition. Data Animal Data Difelikefalin was administered to lactating rats by intravenous injection at doses of 0.6, 2.5, or 10 mg/kg/day from gestation day 7 through lactation day 14. Difelikefalin was detected in the milk of the lactating rats with the concentration ratio for milk:plasma of 0.04 to 0.05 across the doses.

There was no measurable difelikefalin in the plasma of nursing pups.

8.4Pediatric Use The safety and effectiveness of KORSUVA in pediatric patients have not been established.

8.5Geriatric Use Of the 848 subjects in the placebo-controlled studies who received KORSUVA, 278 subjects (32.8%) were 65 years of age and older and 98 subjects (11.6%) were 75 years of age and older. No overall differences in safety or effectiveness of KORSUVA have been observed between patients 65 years of age and older and younger adult subjects, with the exception of the incidence of somnolen…

🤰 Pregnancy ~2 min read ▾

8.1Pregnancy Risk Summary The limited human data on use of KORSUVA in pregnant women are not sufficient to evaluate a drug-associated risk for major birth defects or miscarriage. In animal reproduction studies, intravenous injection of difelikefalin to pregnant rats and rabbits during the period of organogenesis at doses 711 and 10 times the maximum recommended human dose (MRHD), respectively, resulted in no adverse effects in either rats or rabbits (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown.

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Data Animal Data In an embryofetal development study, difelikefalin was administered by intravenous injection to pregnant rats at doses of 0.25, 2.5, and 25 mg/kg/day during the period of organogenesis. Difelikefalin was not associated with embryofetal lethality or fetal malformations.

Difelikefalin increased the incidences of skeletal variations (wavy ribs and incompletely ossified ribs) at the dose of 25 mg/kg/day (711 times the MRHD based on AUC comparison). In an embryofetal development study, difelikefalin was administered by intravenous injection to pregnant rabbits at doses of 0.025, 0.05, and 0.1 mg/kg/day during the period of organogenesis. Maternal toxicity evidenced by decreased maternal body weight gain was noted in all dose groups.

Difelikefalin was not associated with embryofetal lethality or fetal malformations at doses up to 0.1 mg/kg/day (10 times the MRHD based on AUC comparison). In a prenatal and postnatal development study, difelikefalin was administered by intravenous injection to pregnant rats at doses of 0.6, 2.5, and 10 mg/kg/day beginning on gestation day 7 and continuing through lactation day 20. Persisting effects on decreased maternal body weight and/or maternal body weight gain as well as food consumption were noted at doses greater than or equal to 2.5 mg/kg/day (68 times the MRHD based on AUC comparison).

No maternal effects were observed at 0.6 mg/kg/day (14 times the MRHD based on AUC comparison). No difelikefalin-related effects on postnatal developmental, neurobehavioral, or reproductive performance of offspring were noted at doses up to 10 mg/kg/day (282 times the MRHD based on AUC comparison).

🧒 Pediatric Use 16 words ▾

8.4Pediatric Use The safety and effectiveness of KORSUVA in pediatric patients have not been established.

🧓 Geriatric Use 130 words ▾

8.5Geriatric Use Of the 848 subjects in the placebo-controlled studies who received KORSUVA, 278 subjects (32.8%) were 65 years of age and older and 98 subjects (11.6%) were 75 years of age and older. No overall differences in safety or effectiveness of KORSUVA have been observed between patients 65 years of age and older and younger adult subjects, with the exception of the incidence of somnolence which was higher in KORSUVA-treated subjects 65 years of age and older (7.0%) than in KORSUVA-treated subjects less than 65 years of age (2.8%), and was comparable in both placebo age groups (3.0% and 2.1%, respectively).

No differences in plasma concentrations of KORSUVA were observed between subjects 65 years of age and older and younger adult subjects [see Clinical Pharmacology (12.3) ] .

🆘 Overdosage 129 words ▾

10 OVERDOSAGE Single doses of KORSUVA up to 12 times and multiple doses of KORSUVA up to 5 times the recommended dosage of 0.5 mcg/kg were administered in clinical studies in subjects undergoing HD. A dose-dependent increase in adverse reactions, including dizziness, somnolence, mental status changes, paresthesia, fatigue, hypertension, and vomiting, were observed. In the event of overdosage, provide the appropriate medical attention based on patient's clinical status.

Difelikefalin is primarily eliminated by the kidneys with a low plasma protein binding of approximately 23% to 28% in dialysis patients. Hemodialysis for 4 hours using a high-flux dialyzer effectively cleared approximately 70% to 80% of difelikefalin from plasma, and difelikefalin was not detectable in plasma at the end of the second of two dialysis cycles. [see Clinical Pharmacology (12.3) ].

🧬 Clinical Pharmacology ~2 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action KORSUVA is a kappa opioid receptor (KOR) agonist. The relevance of KOR activation to therapeutic effectiveness is not known.

12.2Pharmacodynamics Difelikefalin exposure-response relationships and the time course of pharmacodynamic response are unknown. Cardiac Electrophysiology At a dose 6 times the recommended dosage, difelikefalin does not prolong the QTc interval to any clinically relevant extent.

12.3Pharmacokinetics The pharmacokinetics of difelikefalin is dose proportional over a single dosage range from 1 to 3 mcg/kg (2 to 6 times the recommended dosage) and multiple intravenous dosage range from 0.5 to 2.5 mcg/kg (1 to 5 times the recommended dosage) in chronic kidney disease patients undergoing HD. Steady-state was reached after the second administered dosage and the mean accumulation ratio was up to 1.6. Distribution The mean volume of distribution of difelikefalin is approximately 238 mL/kg.

Difelikefalin binding to human plasma protein in dialysis patients is 23% to 28%. Elimination The half-life of difelikefalin in HD subjects prior to dialysis ranged between 23 and 31 hours. Following administration of radiolabeled difelikefalin, >99% of circulating radioactivity was present in plasma as parent.

Hemodialysis reduced the difelikefalin plasma concentrations by 70% to 80% and difelikefalin was not detectable in plasma after 2 dialysis cycles. Metabolism Difelikefalin is not metabolized by cytochrome P450 (CYP) enzymes CYP1A2, CYP2C19, CYP2C8, CYP2C9, CYP2D6 or CYP3A observed in human hepatic microsomes or hepatocytes, in vitro. Excretion Following administration of difelikefalin to HD patients, 11% of the dosage was excreted in urine, 59% in feces, and 20% in dialysate fluid.

Specific Populations No clinically significant differences in the pharmacokinetics of difelikefalin were observed based on age (25 to 80 years of age), sex, race/ethnicity, or mild-to-moderate hepatic impairment. The effect of severe hepatic impairment on the pharmacokinetics of difelikefalin is unknown [see Use in Specific Populations (8.6) ] . Drug Interaction Studies Clinical Studies No clinical studies evaluating the drug interaction potential of difelikefalin were conducted.

In Vitro Studies Cytochrome P450 (CYP) Enzymes: Difelikefalin did not inhibit CYP enzymes (CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP3A, or CYP2D6), or induce CYP enzymes (CYP1A2, CYP2B6, or CYP3A) and is not a substrate of CYP450 enzymes (CYP1A2, CYP2C19, CYP2C8, CYP2C9, CYP2D6 or CYP3A). Uridine diphosphate (UDP)-glucuronosyl transferase (UGT) Enzymes: Difelikefalin is not an inhibitor of UGT1A3, UGT1A9, or UGT2B7. Transporter Systems: Difelikefalin did not inhibit BCRP, Pgp, OAT1, OAT3, OCT1, OCT2, OATP1B1, OATP1B3, MATE1, or, MATE2-K human transporters and is not a substrate of OAT1, OAT2, OAT3, OATP1A2, OCT2, OCT3, LAT1, PEPT1, PEPT2, ASBT, BSEP, MRP2, OATP1B1, OATP1B3, OATP2B1, OCT1, OCTN1, OCTN2, Pgp, BCRP, OSTα/β, MATE1, or, MATE2-K.

🧬 Mechanism of Action 23 words ▾

12.1Mechanism of Action KORSUVA is a kappa opioid receptor (KOR) agonist. The relevance of KOR activation to therapeutic effectiveness is not known.

📦 How Supplied / Storage and Handling 122 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING How Supplied KORSUVA (difelikefalin) injection is supplied as a sterile, clear and colorless solution in 1.3 mL single-dose, glass vials: NDC 59353-065-01: 65 mcg/1.3 mL (50 mcg/mL) single-dose vial NDC 59353-065-12: Carton containing 12 vials Storage and Handling Store vials at 20°C to 25°C (68°F to 77°F), excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Do not freeze. KORSUVA injection must be administered within 4 hours of syringe preparation; prepared syringes can be stored at ambient temperature 20°C to 25°C (68°F to 77°F) until dosing [see Dosage and Administration (2.2 , 2.3) ] .

KORSUVA injection is supplied in a single-dose vial. Any unused drug remaining after injection must be discarded.

📦 Storage and Handling 82 words ▾

Storage and Handling Store vials at 20°C to 25°C (68°F to 77°F), excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Do not freeze. KORSUVA injection must be administered within 4 hours of syringe preparation; prepared syringes can be stored at ambient temperature 20°C to 25°C (68°F to 77°F) until dosing [see Dosage and Administration (2.2 , 2.3) ] .

KORSUVA injection is supplied in a single-dose vial. Any unused drug remaining after injection must be discarded.

📋 Description 179 words ▾

11 DESCRIPTION KORSUVA (difelikefalin) is a kappa opioid receptor agonist. Difelikefalin is a synthetic peptide with a single stereoisomer and is present as an acetate salt. Difelikefalin acetate is a white to off-white powder with a molecular formula of C 36 H 53 N 7 O 6 ∙xAcOH (1.0≤ × ≤2.0) and a molecular weight of 679.4 g/mol (mono- isotopic; free base).

It is soluble in water. The chemical name of difelikefalin acetate is 4-amino-1-(D-phenylalanyl-D-phenylalanyl-D-leucyl-D-lysyl)piperidine-4-carboxylic acid, acetate salt. The chemical structure is: KORSUVA (difelikefalin) injection is supplied in a single-dose vial containing 65 mcg/1.3 mL (50 mcg/mL) of difelikefalin as a sterile, preservative-free, clear and colorless solution for intravenous injection.

KORSUVA is formulated as an isotonic 40 mM acetate buffer solution with an osmolality of 250 to 350 mOsm and a pH of 4.5. Each milliliter of KORSUVA injection contains 50 mcg of difelikefalin (equivalent to an average of 58.3 mcg of difelikefalin acetate), 1.3 mg of acetic acid, 2.5 mg of sodium acetate trihydrate, 7.2 mg of sodium chloride (to adjust tonicity), and water for injection. Chemical Structure

💬 Information for Patients 141 words ▾

17 PATIENT COUNSELING INFORMATION Dizziness, Somnolence, Mental Status Changes, and Gait Disturbances Inform patients that dizziness, somnolence, mental status changes, and gait disturbances, including falls, can occur during treatment with KORSUVA [see Adverse Reactions (6.1) ] . Somnolence is more likely to happen to patients who are age 65 years or older. Inform patients that concomitant treatment with centrally-acting depressants, sedating antihistamines and opioid analgesics may increase the likelihood of these adverse reactions and these medications should be used with caution during treatment with KORSUVA [see Warnings and Precautions (5.1) ] .

Driving or Operating Machinery Inform patients that KORSUVA may impair the ability to perform potentially hazardous activities such as driving a car or operating heavy machinery. Advise patients not to drive or operate machinery until they know how they will react to KORSUVA [see Warnings and Precautions (5.2) ].

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