Nourianz Generic: When Will Generic Istradefylline Be Available?
This page is aggregated from FDA records, court filings and company announcements. Coded and designed by Dr. Brian Staiger, PharmD, BCPS
Updated October 9, 2026 How we build our data
Nourianz Generic at a Glance
Four quick answers from FDA records and our estimate.
- When is the first generic expected? January 2028 About 16 months away Why then?
- Has the FDA approved a generic? Not yet None in the FDA’s records yet Why not yet?
- When does the last patent end? January 2028 2 patents listed with the FDA
- Can you buy a generic today? Not yet No company lists one for sale
Generic istradefylline is expected to be available in January 2028, about 16 months away. None is for sale yet.
Why January 2028?
It is when Nourianz’s patent 7,727,993 ends. That patent covers the product’s formulation and a way of using it, and once it ends, generics can go on sale as soon as the FDA approves them. We rate it toss-up: still unsettled. Just as likely to slip as to hold.
Why hasn’t the FDA approved a generic yet?
That is normal before a launch. The FDA usually can’t give a generic its final approval while a patent or exclusivity still blocks it, so final approval often comes close to the day the generic can be sold. No company holds a “tentative” approval yet either (the FDA’s word for a generic that is ready but still blocked).
Will the generic cost less?
Usually, and more so as more companies sell one. One company has applied to the FDA to make it. In the FDA’s study of past launches, pharmacies paid about 31% less once one company sold a generic. See the price pattern
What should I do now?
Keep taking Nourianz as prescribed. When a generic arrives, your pharmacy may switch you to it automatically, and it may look different. What a generic means for you
Our month is only an estimate based on available information, so we never name a day.
Nourianz by the Numbers
- Reason
- Patent expiresA patent that protects the brand runs out. After that, approved generics can be sold.
- How sure
- Toss-up Still unsettled. Just as likely to slip as to hold.
- Price competition
- Low 1 company has filed, 1 first in line
- Brand sales
- $24M a yearSmaller seller
- FDA approved 2019 August 2019 FDA Orange Book
- Patents listed 2 last runs to January 2028 FDA Orange Book
- Medicare Part D spent $53.6M in 2025, for 3,299 people CMS Part D Spending by Drug
- Medicaid prescriptions 331 in the last four reported quarters, $891.8K CMS Medicaid drug utilization, to Q1 2026
Nourianz’s Road to a Generic
Nourianz has had the market to itself since the FDA approved it in August 2019 (Kyowa Kirin Inc). Its 2 listed patents run to January 2028. Generic companies have challenged its patents with the FDA since August 2025.
The first generic of Nourianz is expected in January 2028.
Why that month: patent 7,727,993, on the product’s formulation and a way of using it, ends then.
Each bar runs from the brand’s approval to the day that protection ends. The green band is our projection for the first generic: a month, never a day, because legal dates move and a generic reaches shelves days to weeks after it is allowed. Sources: FDA Orange Book; the expected month from court records and company announcements.
Nourianz Patents and FDA Protections
Every patent and exclusivity the FDA Orange Book lists for Nourianz’s own applications. A protection running past the expected month does not mean the date is wrong: a settlement or a court ruling can let a generic in before a patent ends, and a patent on one formulation or use does not block every generic.
The one that matters for a generic launch: patent 7,727,993, which ends in January 2028, the month the first generic is expected.
| Patent | What it covers | Protects until | Status |
|---|---|---|---|
| 8,318,201 | The product’s formulation | September 2027 | Active |
| 7,727,993 Sets the expected month of generic availability | The product’s formulation; a way of using it (U-2623) | January 2028 | Active |
Source: FDA Orange Book, application 022075. Patent numbers open the patent on Google Patents.
Patent Challenges to Nourianz
The first patent challenge to Nourianz reached the FDA in August 2025, from one company on that first day. The FDA has not approved a first challenger’s generic yet.
What Is a Patent Challenge?
A generic company that wants to sell its version before Nourianz’s patents run out can tell the FDA that a patent is invalid, or that its version does not infringe it. The FDA calls this a “Paragraph IV certification.” The brand company usually sues, and the FDA then generally cannot approve that generic for up to 30 months while the case runs. To reward going first, the companies that challenge first can get a 180-day head start: the FDA cannot approve the generics that came after them until it ends.
| Product | First challenged | Companies that day | 180-day head start | First challenger’s generic | Challenged patents run to | |
|---|---|---|---|---|---|---|
| Approved | On sale | |||||
| Tablets, 20 mg and 40 mg | August 2025 | 1 company | No decision yet | Not yet | Not yet | January 2028 |
Source: the FDA’s Paragraph IV Patent Certifications list, as of September 2026. The FDA began posting the 180-day decisions and the first challenger’s approval and first sale in June 2019: an older entry it has not updated since reads “Not posted”, and “Not yet” means the list records no such event. “Companies that day” is the FDA’s count of challenges that arrived on the first day.
Who Is Lined Up to Make Generic Istradefylline
Three steps stand between a brand and a generic you can buy: a company applies to the FDA, the FDA approves it, and the company starts selling it.
Applied to the FDA
One company has applied to the FDA to make generic istradefylline.
The FDA names a company only once it approves its application, even tentatively, and it has not done that for this one yet, so the company is not named here. Names often come out in the brand company’s patent lawsuits or in the companies’ own announcements.
First in line. One of them was first in line: the first company to challenge the brand’s patents can earn 180 days on the market before the other generics, which is why being first matters.
Generic companies have challenged Nourianz’s patents with the FDA since August 2025: see the patent challenges.
Approved by the FDA
Not yet. The FDA has not approved a generic istradefylline. Final approval often comes close to the day a generic can be sold.
For Sale in Pharmacies
Not yet. No company lists a generic istradefylline for sale with the FDA.
Sources: how many companies have applied, from court records and company announcements; approved generics from the FDA Orange Book; tentative approvals from Drugs@FDA; what is for sale from the FDA NDC Directory. The FDA does not disclose an application before it approves it (21 CFR 314.430).
Nourianz Price: What Pharmacies Pay and What Generics Usually Do
What a Generic Could Cost
How we estimate it. The national survey of what pharmacies pay (NADAC) has no recent price for Nourianz, so we cannot show dollars. Here is the FDA’s finding of how far the price pharmacies pay usually falls as generic companies join: about 31% with one company, 44% with two, 73% with four and over 95% with six or more (the typical drop for every drug whose first generic came out from 2015 to 2017).
Median prices pharmacies paid for the generic (invoice prices), compared with the brand’s price before generic entry, from FDA’s 2019 analysis “Generic Competition and Drug Prices”. At the manufacturer’s price FDA found steeper drops (about 39%, 54%, 79% and over 95%), the figures quoted elsewhere on this tracker. A typical pattern, not a price quote for this medicine.
What Medicare and Medicaid Spend on Nourianz
Big public spending is part of why generic makers line up for a medicine, and why its first generic matters beyond the pharmacy counter. Figures are before manufacturer rebates, which are confidential.
Medicare Part D Spending
What Medicare drug plans spent on Nourianz, before manufacturer rebates.
- $11.7M
- January to March 2026, the latest CMS has posted
For 2,141 people, about $2,659 per prescription fill - $53.6M
- 2025, the whole year
For 3,299 people, about $2,623 per prescription fill
See the numbers
| Period | Spending | People | Per fill |
|---|---|---|---|
| January to March 2026 | $11,740,205 | 2,141 | $2,659.16 |
| 2025 | $53,602,815 | 3,299 | $2,623.47 |
Source: CMS Medicare Part D Spending by Drug, matched by the brand name Nourianz only, so no generic is counted in it. What CMS says it is used for: Istradefylline is used by people with Parkinson's disease taking carbidopa/levodopa to reduce the amount of "off" time (periods of slow movement or stiffness).
Medicaid Prescriptions by Quarter
331 prescriptions in the four quarters to Q1 2026, $891.8K paid.
See the numbers
| Quarter | Prescriptions | Medicaid paid |
|---|---|---|
| Q1 2026 | 43 | $129,138 |
| Q4 2025 | 80 | $212,578 |
| Q3 2025 | 118 | $303,688 |
| Q2 2025 | 90 | $246,434 |
| Q1 2025 | 112 | $299,828 |
Source: CMS Medicaid State Drug Utilization Data, over Nourianz’s own package codes.
Nourianz Strengths and Forms
| Strength | Form | How it is taken | Approved | Status |
|---|---|---|---|---|
| 20MG | Tablet | Oral | August 2019 | Prescription reference product |
| 40MG | Tablet | Oral | August 2019 | Prescription reference product |
Source: FDA Orange Book, Kyowa Kirin Inc. Listed for sale today by Kyowa Kirin, Inc. (FDA NDC Directory).
Nourianz NDC Codes and Packages
Each Nourianz package sold today has its own NDC, the product number printed on the box and on the pharmacy label. Open one to see that package’s details, what pharmacies pay for it and its patent timeline.
| NDC | Product | Package | Company |
|---|---|---|---|
| 42747-0602-07 | ISTRADEFYLLINE 20 mg/1 tablet, film coated | blister pack of 7 tablets | Kyowa Kirin, Inc. |
| 42747-0602-07 | ISTRADEFYLLINE 20 mg/1 tablet, film coated | blister pack of 7 tablets | Kyowa Kirin, Inc. |
| 42747-0602-90 | ISTRADEFYLLINE 20 mg/1 tablet, film coated | bottle of 90 tablets | Kyowa Kirin, Inc. |
| 42747-0602-90 | ISTRADEFYLLINE 20 mg/1 tablet, film coated | bottle of 90 tablets | Kyowa Kirin, Inc. |
| 42747-0604-07 | ISTRADEFYLLINE 40 mg/1 tablet, film coated | blister pack of 7 tablets | Kyowa Kirin, Inc. |
| 42747-0604-07 | ISTRADEFYLLINE 40 mg/1 tablet, film coated | blister pack of 7 tablets | Kyowa Kirin, Inc. |
| 42747-0604-90 | ISTRADEFYLLINE 40 mg/1 tablet, film coated | bottle of 90 tablets | Kyowa Kirin, Inc. |
| 42747-0604-90 | ISTRADEFYLLINE 40 mg/1 tablet, film coated | bottle of 90 tablets | Kyowa Kirin, Inc. |
Source: the FDA NDC Directory, current listings only. Only packages sold under Nourianz’s own FDA approval (NDA 22075) are listed, never a generic. Some codes belong to companies that repackage Nourianz: it is the same medicine in a different package.
What a Generic Nourianz Means for You
Nothing Changes Until It Is in Pharmacies
Until a generic is actually for sale, keep filling Nourianz as usual. When one arrives, there is nothing you need to sign up for.
Your Pharmacy May Switch You Automatically
Every state lets pharmacists fill a brand-name prescription with an FDA-approved generic rated as equivalent to it, and about 19 states require them to, unless your prescriber writes “dispense as written” or “brand medically necessary” on the prescription. Some states ask the pharmacist to tell you, or to get your OK first. A study of every state’s law has the details.
It Will Probably Look Different
US trademark law does not let a generic look exactly like the brand, so the color, shape or markings usually change. The active ingredient, strength and form are the same. An “authorized generic,” made by or for the brand’s own company, can look identical. The FDA explains.
Your Insurance May Change Too
Once a lower-cost version is available, many insurance plans charge more for the brand, or stop covering it. Your plan’s drug list (formulary) says how.
Until a generic is on US pharmacy shelves, be careful with websites that offer “generic Nourianz”. The FDA warns that unlicensed online pharmacies sell counterfeit and unapproved medicines; its BeSafeRx page shows how to check a pharmacy.
Questions people ask about Nourianz
Is there a generic for Nourianz right now?
No. As of October 9, 2026 no generic istradefylline is listed for sale in the FDA NDC Directory.
When will Nourianz go generic?
January 2028 is the expected month, and that is toss-up but not certain. It is when Nourianz’s patent 7,727,993 ends. That patent covers the product’s formulation and a way of using it, and once it ends, generics can go on sale as soon as the FDA approves them.
Will generic istradefylline be the same as Nourianz?
Yes in the ways that matter: the same active ingredient, strength and form, with proof that it reaches your blood the same way. Inactive ingredients can differ, which is why some people notice a different look or taste.
How much will the generic cost?
Nobody can say for sure before launch. One company has applied to the FDA to make it. In the FDA’s study of past launches, pharmacies paid about 31% less once one company sold a generic. That is a pattern from past launches, not a prediction for this one.
Has the FDA approved a generic Nourianz?
Not yet. The FDA Orange Book lists no approved generic version of Nourianz.
When does the Nourianz patent expire?
The FDA Orange Book lists 2 patents for Nourianz; the last runs to January 2028. The one behind the expected month is patent 7,727,993, which ends in January 2028. A patent date is not the launch date: settlements and court rulings often bring a generic earlier, and FDA approval or a company’s own plans can make it later. The expected month on this page (January 2028) weighs all of that.
Has anyone challenged the Nourianz patents?
Yes. The first patent challenge to Nourianz reached the FDA in August 2025, from one company on that first day. The FDA has not approved a first challenger’s generic yet. A patent challenge (a “Paragraph IV certification”) is a generic company telling the FDA that a patent listed for the brand is invalid or will not be infringed by its version. The first companies to file one can earn a 180-day head start, during which the FDA cannot approve the generics that filed after them.
Changes to This Projection
- First generic expected January 2028 on this month’s schedule. A line is added here whenever a monthly update moves the month, the reason or how sure it is.
Every change to the expected month is logged here with the month we saw it.
Also Going Generic
- YutiqFluocinolone AcetonideJanuary 2028
- BrukinsaZanubrutinib2036 to 2037
- FlyrcadoFlurpiridaz F 18December 2036
- LivdelziSeladelpar LysineMarch 2038
- TlandoTestosterone UndecanoateApril 2041
- PonvoryPonesimodOctober 2042
About Nourianz
- Generic name istradefylline
- How it is taken By mouth
- Company Kyowa Kirin Inc
- Patent challenges Since August 2025 (FDA)
- More drugs Brand-name drugs starting with N
- Have a question? A pharmacist answers, free. Ask about Nourianz
Sources. The expected month: FDA Paragraph IV Patent Certifications list, federal court records, company announcements and securities filings (settlement dates, launch plans, sales). The record on this page: FDA Orange Book, Drugs@FDA (tentative approvals), FDA NDC Directory, FDA Paragraph IV Patent Certifications list, CMS Medicare Part D Spending by Drug, Medicaid State Drug Utilization Data, FDA, Generic Competition and Drug Prices (2019). Updated October 9, 2026. Information, not medical advice.