ISTRADEFYLLINE - Generic Drug Details

What are the generic drug sources for istradefylline and what is the scope of patent protection?

Istradefylline is the generic ingredient in one branded drug marketed by Kyowa Kirin and is included in one NDA. There are two patents protecting this compound. Additional information is available in the individual branded drug profile pages.

Istradefylline has forty-nine patent family members in seventeen countries.

There is one drug master file entry for istradefylline. One supplier is listed for this compound.

Summary for ISTRADEFYLLINE

International Patents:	49
US Patents:	2
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	92
Clinical Trials:	25
What excipients (inactive ingredients) are in ISTRADEFYLLINE?	ISTRADEFYLLINE excipients list
DailyMed Link:	ISTRADEFYLLINE at DailyMed

DrugPatentWatch^® Estimated Loss of Exclusivity (LOE) Date for ISTRADEFYLLINE

Dosage:

TABLET;ORAL

^*The generic entry opportunity date is the latter of the last compound-claiming patent and the last regulatory exclusivity protection. Many factors can influence early or later generic entry. This date is provided as a rough estimate of generic entry potential and should not be used as an independent source.

Recent Clinical Trials for ISTRADEFYLLINE

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
Kyowa Kirin, Inc.	Phase 4
Georgetown University	Phase 4
ALS Association	Phase 1/Phase 2

See all ISTRADEFYLLINE clinical trials

Anatomical Therapeutic Chemical (ATC) Classes for ISTRADEFYLLINE

N04CX	Other antiparkinson drugs
N04C	OTHER ANTIPARKINSON DRUGS
N04	ANTI-PARKINSON DRUGS
N	Nervous system

Paragraph IV (Patent) Challenges for ISTRADEFYLLINE

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
NOURIANZ	Tablets	istradefylline	20 mg and 40 mg	022075	1	2025-08-13

US Patents and Regulatory Information for ISTRADEFYLLINE

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-001	Aug 27, 2019		RX	Yes	No			Y
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-002	Aug 27, 2019		RX	Yes	Yes			Y
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-001	Aug 27, 2019		RX	Yes	No			Y
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-002	Aug 27, 2019		RX	Yes	Yes			Y

Expired US Patents for ISTRADEFYLLINE

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-002	Aug 27, 2019
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-001	Aug 27, 2019
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-002	Aug 27, 2019
Kyowa Kirin	NOURIANZ	istradefylline	TABLET;ORAL	022075-001	Aug 27, 2019

EU/EMA Drug Approvals for ISTRADEFYLLINE

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Kyowa Kirin Holdings B.V.	Nouryant	istradefylline	EMEA/H/C/005308Istradefylline is indicated in adults as an adjunctive treatment to levodopa based regimens in patients with Parkinson’s disease (PD) experiencing “OFF” time.	Refused	no	no	no		2022-01-06

International Patents for ISTRADEFYLLINE

Country	Patent Number	Title	Estimated Expiration
Taiwan	I346114
South Korea	101135917
Eurasian Patent Organization	200400982
Spain	2534220
European Patent Office	2044940
Spain	2716404

Market Dynamics and Financial Trajectory for Istradefylline

Last updated: July 28, 2025

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Introduction

Istradefylline, marketed predominantly under the brand name Nourianz, is an oral selective adenosine A2A receptor antagonist approved for the management of Parkinson’s disease (PD). Since its approval by the U.S. Food and Drug Administration (FDA) in 2019 and subsequent regulatory clearances across multiple regions, Istradefylline’s market landscape has evolved amid a competitive environment characterized by novel therapies and shifting patient needs. This analysis examines the current market dynamics influencing Istradefylline's trajectory and evaluates its financial prospects within the global pharmaceutical arena.

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Market Landscape and Growth Drivers

Global Parkinson’s Disease Treatment Market

The Parkinson’s disease therapeutics market has witnessed consistent growth due to rising prevalence driven by aging global populations and increasing awareness of early diagnosis. According to the World Parkinson’s Coalition, approximately 6 million individuals worldwide are affected by PD, with projections estimating this figure will reach 12 million by 2040.[1] The expansion of the market creates favorable conditions for new pharmacological agents, including Istradefylline.

Role of Istradefylline in PD Management

Istradefylline’s mechanism, targeting the adenosine A2A receptor, offers a novel adjunct therapy to dopamine replacement strategies. It addresses motor fluctuations, a common complication arising from levodopa treatment, thereby filling a treatment gap.[2] Recent clinical data suggest its efficacy in reducing 'off' episodes, supporting its utility within combination regimens, and bolstering its market adoption.

Pricing, Reimbursement, and Regulatory Environment

In the U.S., Istradefylline’s pricing generally ranges between $5,000 and $7,000 annually, aligning with other adjunctive PD therapies. Reimbursement policies and insurance coverage significantly influence prescription rates. Notably, regulatory approvals in Japan (2013), Europe (2019), and other regions vary in scope, affecting market penetration. Countries with stringent approval processes and limited healthcare budgets may pose barriers to rapid adoption.

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Market Competitors and Differentiators

Istradefylline faces competition from established Dopaminergic agents, COMT inhibitors, MAO-B inhibitors, and emerging gene therapies. Notable players include:

• Dopamine agonists (e.g., pramipexole, ropinirole)
• COMT inhibitors (e.g., entacapone)
• MAO-B inhibitors (e.g., selegiline, rasagiline)
• Emerging therapies: gene-editing techniques and non-dopaminergic modulators

However, Istradefylline's unique mechanism offers potential advantages, particularly in reducing motor fluctuations without exacerbating dyskinesia, thereby differentiating its value proposition.

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Financial Projections and Revenue Outlook

Historical Sales Performance

Since its launch, Istradefylline has rapidly gained approval in multiple markets. In the U.S., the drug reported sales of approximately $150 million in 2021, with growth driven by increasing prescriber familiarity and expanding indications.[3] Japan remains its largest market share, contributing significantly to revenue.

Future Revenue Trajectory

Analysts project a Compound Annual Growth Rate (CAGR) of approximately 8-10% over the next five years, contingent on:

• Market expansion: Additional approvals in Europe, Asia, and emerging economies
• Increased physician adoption: Education campaigns and positive clinical outcomes
• Pricing strategies: Value-based pricing aligned with clinical benefits

Emerging data supporting its efficacy could result in broader adoption, potentially elevating revenue beyond current forecasts.

Potential Challenges Impacting Revenue

• Generic competition: While still under patent, eventual biosimilars or generic entrants could erode market share.
• Pipeline competition: New non-dopaminergic agents could challenge Istradefylline’s positioning.
• Regulatory and reimbursement hurdles: Delays or unfavorable pricing policies could dampen sales.

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Market Risks and Opportunities

Risks

• Limited long-term safety data: Ongoing post-marketing surveillance is essential to sustain confidence.
• Competitive landscape shifts: A surge of innovative therapies could marginalize Istradefylline.
• Regulatory delays in additional indications or geographical expansion.

Opportunities

• Combination therapy positioning: Synergy with other PD drugs enhances its clinical utility.
• Expanded indications: Potential for use in other neurodegenerative or movement disorders.
• Growing prevalence: As the PD patient base expands, demand for adjunct therapies increases.

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Regulatory and Strategic Outlook

Currently, regulatory bodies recognize the drug’s efficacy profile, encouraging further approvals and label expansions. Strategic alliances and licensing agreements could accelerate market penetration, especially in regions where local regulatory agencies favor innovative therapies.

Furthermore, investment in real-world evidence (RWE) collection and post-marketing studies can bolster its clinical value proposition, fostering wider payer acceptance. As genomic and precision medicine evolve, Istradefylline’s role might expand, especially if personalized treatment regimens emphasizing adenosine receptor modulation prove advantageous.

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Key Takeaways

• Market Positioning: Istradefylline addresses a niche in PD management, offering a unique mechanism that complements existing therapies and reduces 'off' episodes.

• Growth Drivers: Aging populations and rising PD prevalence underpin demand; clinical efficacy and favorable safety profiles facilitate adoption.

• Revenue Forecasts: Projected CAGR of 8-10% reflects promising growth potential, primarily driven by geographical expansion and increased prescriber awareness.

• Challenges: Competition from traditional dopaminergic agents, regulatory hurdles, and long-term safety data are key risk factors.

• Strategic Opportunities: Leveraging combination therapies, expanding indications, and enhancing market access can bolster financial trajectory.

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FAQs

1. What is Istradefylline, and how does it function in Parkinson’s treatment?
   Istradefylline is a selective adenosine A2A receptor antagonist that modulates neural pathways involved in PD. It reduces motor fluctuations and enhances the efficacy of dopamine-based therapies.

2. In which markets is Istradefylline currently approved?
   Approved in the U.S., Japan, and Europe, with ongoing efforts to expand into emerging economies and obtain additional regional approvals.

3. What are the primary factors influencing Istradefylline’s market growth?
   Increasing PD prevalence, clinical efficacy in reducing 'off' episodes, the aging population, and strategic market expansion efforts.

4. What challenges could hinder Istradefylline’s growth?
   Competitive therapies, regulatory delays, reimbursement restrictions, and the potential emergence of superior treatments.

5. How does Istradefylline compare to other PD therapies in terms of efficacy?
   It provides a mechanism targeting non-dopaminergic pathways, offering benefits in managing motor fluctuations with a favorable safety profile, making it a valuable adjunct in PD therapy.

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References

1. World Parkinson’s Coalition. Parkinson’s Disease Facts & Figures. [Online]. Available at: www.wpco.org
2. Fox, S. H., et al. (2018). "Paradigm Shift in Parkinson’s Disease Therapy." Neurotherapeutics.
3. IQVIA. (2022). Pharmaceutical Sales Data.

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Note: This analysis offers a current perspective based on publicly available data and market estimations. Changes in regulatory policies, clinical data, or competitive dynamics could materially affect Istradefylline’s financial trajectory.