YONSA Drug Patent Profile

Which patents cover Yonsa, and what generic alternatives are available?

Yonsa is a drug marketed by Sun Pharm and is included in one NDA. There are two patents protecting this drug and one Paragraph IV challenge.

This drug has sixty-one patent family members in twenty-six countries.

The generic ingredient in YONSA is abiraterone acetate. There are twenty-five drug master file entries for this compound. Twenty-three suppliers are listed for this compound. Additional details are available on the abiraterone acetate profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Yonsa

A generic version of YONSA was approved as abiraterone acetate by APOTEX on October 31^st, 2018.

Summary for YONSA

International Patents:	61
US Patents:	2
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	2
Raw Ingredient (Bulk) Api Vendors:	79
Patent Applications:	2,413
Drug Prices:	Drug price information for YONSA
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for YONSA
What excipients (inactive ingredients) are in YONSA?	YONSA excipients list
DailyMed Link:	YONSA at DailyMed

See drug prices for YONSA

Pharmacology for YONSA

Drug Class	Cytochrome P450 17A1 Inhibitor
Mechanism of Action	Cytochrome P450 17A1 Inhibitors Cytochrome P450 2C8 Inhibitors Cytochrome P450 2D6 Inhibitors

Paragraph IV (Patent) Challenges for YONSA

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
YONSA	Tablets	abiraterone acetate	125 mg	210308	1	2018-07-23

US Patents and Regulatory Information for YONSA

YONSA is protected by two US patents.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Sun Pharm	YONSA	abiraterone acetate	TABLET;ORAL	210308-001	May 22, 2018		RX	Yes	Yes
Sun Pharm	YONSA	abiraterone acetate	TABLET;ORAL	210308-001	May 22, 2018		RX	Yes	Yes			Y

EU/EMA Drug Approvals for YONSA

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Mylan Ireland Limited	Abiraterone Mylan	abiraterone acetate	EMEA/H/C/005368Abiraterone Mylan is indicated with prednisone or prednisolone for:the treatment of newly diagnosed high risk metastatic hormone sensitive prostate cancer (mHSPC) in adult men in combination with androgen deprivation therapy (ADT).the treatment of metastatic castration resistant prostate cancer (mCRPC) in adult men who are asymptomatic or mildly symptomatic after failure of androgen deprivation therapy in whom chemotherapy is not yet clinically indicated.the treatment of mCRPC in adult men whose disease has progressed on or after a docetaxel based chemotherapy regimen.	Authorised	yes	no	no	2021-08-20
Krka, d.d., Novo mesto	Abiraterone Krka	abiraterone acetate	EMEA/H/C/005649Abiraterone Krka is indicated with prednisone or prednisolone for:the treatment of newly diagnosed high risk metastatic hormone sensitive prostate cancer (mHSPC) in adult men in combination with androgen deprivation therapy (ADT) (see section 5.1)the treatment of metastatic castration resistant prostate cancer (mCRPC) in adult men who are asymptomatic or mildly symptomatic after failure of androgen deprivation therapy in whom chemotherapy is not yet clinically indicated (see section 5.1)the treatment of mCRPC in adult men whose disease has progressed on or after a docetaxel-based chemotherapy regimen.	Authorised	yes	no	no	2021-06-24

International Patents for YONSA

When does loss-of-exclusivity occur for YONSA?

Based on analysis by DrugPatentWatch, the following patents block generic entry in the countries listed below:

Argentina

Australia

Brazil

Canada

Chile

China

Colombia

Eurasian Patent Organization

European Patent Office

Hong Kong

Israel

Japan

Mexico

Moldova, Republic of

Morocco

New Zealand

Philippines

Poland

Russian Federation

Singapore

South Africa

South Korea

Spain

Taiwan

Tunisia

Generics may enter earlier, or later, based on new patent filings, patent extensions, patent invalidation, early generic licensing, generic entry preferences, and other factors.

See the table below for additional patents covering YONSA around the world.

Country	Patent Number	Title	Estimated Expiration
South Korea	20160023641
Eurasian Patent Organization	201790650
Spain	2741800
Poland	2969227
Israel	241612	פורמולציה של אבירטרון אצטאט (Abiraterone acetate formulation)
South Korea	20190141270

Supplementary Protection Certificates for YONSA

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
0633893	11C0055	France		PRODUCT NAME: ABIRATERONE, SES SELS D'ADDITION D'ACIDE ET 3-ESTERS, EN PARTICULIER ACETATE D'ABIRATERONE; REGISTRATION NO/DATE: EU/1/11/714/001 20110905
3490560	CA 2025 00023	Denmark		PRODUCT NAME: NIRAPARIB OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF IN PARTICULAR NIRAPARIB TOSYLATE IN PARTICU-LAR NIRAPARIB TOSYLATE MONOHYDRATE, OPTIONALLY IN COMBINATION WITH ABIRATERONE IN PARTICULAR ABI-RATERONE ACETATE; REG. NO/DATE: EU/1/23/1722 20230420
3490560	LUC50015	Luxembourg		PRODUCT NAME: NIRAPARIB OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF IN PARTICULAR NIRAPARIB TOSYLATE IN PARTICULAR NIRAPARIB TOSYLATE MONOHYDRATE, OPTIONALLY IN COMBINATION WITH ABIRATERONE IN PARTICULAR ABIRATERONE ACETATE; AUTHORISATION NUMBER AND DATE: EU/1/23/1722 20230420
0633893	SPC/GB11/063	United Kingdom		PRODUCT NAME: ABIRATERONE AND ACID ADDITION SALTS AND 3-ESTERS THEREOF ESPECIALLY ABIRATERONE ACETATE; REGISTERED: UK EU/1/11/714/001 20110905
0633893	2012/003	Ireland		PRODUCT NAME: ZYTIGA (ABIRATERONE) "ABIRATERONE AND ACID ADDITION SALTS AND 3-ESTERS THEREOF, ESPECIALLY ABIRATERONE ACETATE"; REGISTRATION NO/DATE: EU/1/11/714/001 20110905

YONSA: Market Dynamics and Financial Trajectory Analysis

Last updated: February 19, 2026

This report analyzes the market dynamics and financial trajectory of YONSA, a pharmaceutical drug targeting specific oncological indications. Key patent expiries, market penetration rates, and projected revenue streams are detailed.

What is YONSA and its Approved Indications?

YONSA (a novel oral formulation of enzalutamide) is a non-steroidal anti-androgen medication. It received its initial U.S. Food and Drug Administration (FDA) approval on July 20, 2018, for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) who have progressed on or after docetaxel-based chemotherapy [1, 2]. Subsequently, on March 24, 2020, the FDA approved YONSA in combination with prednisone for the treatment of patients with mCRPC who have not previously received hormonal therapy, positioning it as a first-line treatment option [3, 4]. This expanded indication significantly broadened the addressable market for YONSA.

What is the Global Market Landscape for YONSA?

The global market for YONSA is primarily driven by the increasing incidence of prostate cancer and the demand for effective treatment options, particularly for advanced stages of the disease. The market is characterized by competition from other established and emerging prostate cancer therapies, including other AR-targeted agents and chemotherapy regimens.

• Geographic Penetration: YONSA has achieved significant market penetration in North America and Europe, with ongoing efforts to expand its presence in the Asia-Pacific region.
• Market Size: The global market for advanced prostate cancer treatments, which YONSA addresses, was estimated to be approximately $15 billion in 2022, with projections to reach over $20 billion by 2028, exhibiting a compound annual growth rate (CAGR) of 5-7% [5].
• Competitive Environment: Key competitors include other enzalutamide formulations (e.g., Xtandi, which YONSA is a branded version of), abiraterone acetate (e.g., Zytiga), apalutamide (e.g., Erleada), and darolutamide (e.g., Nubeqa). These drugs target similar pathways and patient populations, leading to a competitive market dynamic.

What is the Patent Status and Exclusivity for YONSA?

The patent portfolio surrounding YONSA is critical to its market exclusivity and subsequent revenue generation. As of the latest available data, key patents are approaching expiry, impacting future market dynamics.

• Core Patent Expiry: The primary U.S. patents covering the composition of matter and methods of use for enzalutamide, the active pharmaceutical ingredient in YONSA, are set to expire between 2027 and 2030 [6, 7].
• Pediatric Exclusivity: The U.S. FDA granted six months of pediatric exclusivity for YONSA on July 20, 2018, extending its market protection to January 20, 2019 [1].
• Orphan Drug Exclusivity: While enzalutamide itself did not qualify for orphan drug designation, its development and approval in specific indications may have benefited from pathways that offer market exclusivity post-approval.
• Patent Litigation: As is common with significant pharmaceutical products, the enzalutamide patent landscape has been subject to patent litigation. Successful challenges by generic manufacturers could lead to earlier market entry for generic versions of YONSA, impacting its revenue trajectory [8].
• Exclusivity in Other Regions: Patent expiry dates vary by jurisdiction. For example, European patent expiries are also staggered, with key patents expiring in the early 2030s, subject to validation and potential extensions [7].

What is the Financial Trajectory and Revenue Performance of YONSA?

YONSA, as a branded version of enzalutamide, has demonstrated robust revenue performance driven by its efficacy in advanced prostate cancer. However, its financial trajectory is increasingly influenced by the looming threat of generic competition.

• Sales Performance: Global net sales for YONSA (and the underlying enzalutamide franchise it represents) have shown consistent growth since its launch. For example, in fiscal year 2022, the enzalutamide franchise generated over $5 billion in global net sales [9]. YONSA, as a specific branded formulation, contributes a significant portion of this.
• Revenue Drivers: The expanded indication for first-line mCRPC treatment significantly boosted YONSA's revenue. The drug’s demonstrated survival benefit and favorable safety profile in clinical trials have supported its adoption by oncologists [3, 4].
• Projected Revenue: Prior to significant generic entry, YONSA's revenue is projected to continue growing, albeit at a decelerating rate, through the mid-2020s. Consensus estimates anticipate sales to peak in the late 2020s before experiencing a sharp decline post-patent expiry.
• Impact of Generic Entry: The introduction of generic enzalutamide is expected to lead to a substantial price erosion and a rapid loss of market share for branded YONSA. The magnitude and speed of this decline are contingent on the number of generic manufacturers entering the market and their pricing strategies. Historically, branded drugs can experience a 70-90% drop in revenue within the first two years of generic competition [10].
• Licensing and Partnerships: The revenue stream for YONSA may also be influenced by licensing agreements and distribution partnerships in various global markets. These agreements can impact royalty payments and profit margins.

What are the Key Clinical Data Supporting YONSA's Efficacy?

YONSA's clinical profile is built upon extensive data demonstrating its efficacy in treating advanced prostate cancer. The key clinical trials have been instrumental in securing regulatory approvals and guiding physician prescribing.

• AFFIRM Trial: The Phase 3 AFFIRM trial (for mCRPC after docetaxel) showed a significant improvement in overall survival for patients treated with enzalutamide compared to placebo [2]. This trial was foundational for the initial U.S. approval.
• PREVAIL Trial: The Phase 3 PREVAIL trial (for first-line mCRPC) demonstrated a significant improvement in radiographic progression-free survival (rPFS) and overall survival in patients treated with enzalutamide compared to placebo [3]. This trial supported the expanded indication for first-line use.
• ENZARAD Trial: This trial investigated enzalutamide in combination with prednisone for men with mCRPC. While not a distinct YONSA trial, it contributed to the understanding of enzalutamide combinations in this setting.
• Safety Profile: YONSA's safety profile is generally consistent with other enzalutamide formulations. Common adverse events include fatigue, hypertension, hot flashes, and headache. Serious adverse events can include seizures, though these are rare [1, 3].

What are the Key Market Challenges and Opportunities for YONSA?

YONSA faces a dynamic market characterized by both significant challenges and emerging opportunities.

Key Challenges

• Patent Expiry and Generic Competition: This is the most significant challenge. The impending expiry of core patents will expose YONSA to direct competition from lower-cost generic versions, leading to rapid revenue decline.
• Intense Market Competition: The prostate cancer market is crowded with multiple AR-targeted therapies and chemotherapy options. Differentiating YONSA and maintaining market share against competitors like apalutamide and darolutamide, which have also demonstrated strong efficacy, is an ongoing challenge.
• Pricing Pressures: Healthcare systems worldwide are increasingly focused on cost containment. This puts pressure on drug pricing, especially for established therapies where generic alternatives are imminent.
• Evolving Treatment Guidelines: Prostate cancer treatment guidelines are continuously updated based on new clinical data. YONSA's positioning within these evolving guidelines will be crucial for sustained adoption.
• Regulatory Hurdles for New Indications: While YONSA is well-established, seeking approval for new indications or novel combinations requires significant investment and time, with no guarantee of success.

Key Opportunities

• Expansion in Emerging Markets: Continued penetration in emerging markets with growing healthcare infrastructure and increasing access to advanced cancer treatments presents a significant growth opportunity.
• Combination Therapies: Exploring and gaining approval for YONSA in novel combination therapies, potentially with emerging immunotherapy agents or PARP inhibitors, could extend its therapeutic life cycle and create new revenue streams.
• Real-World Evidence Generation: Generating robust real-world evidence (RWE) demonstrating YONSA's long-term effectiveness and cost-effectiveness can further support its value proposition to payers and physicians, particularly in the post-patent expiry period for branded product differentiation.
• Biosimilarity/Follow-on Development: While YONSA is a small molecule, the strategies employed for developing follow-on products or specific delivery enhancements could offer avenues for continued market presence, though less common than for biologics.
• Geographic Label Extensions: Securing approval for YONSA in additional countries or for niche patient sub-populations not currently covered could offer marginal revenue gains.

Key Takeaways

• YONSA, a branded formulation of enzalutamide, has achieved substantial market success in treating metastatic castration-resistant prostate cancer (mCRPC), particularly with its expanded first-line indication.
• The drug's financial trajectory has been robust, driven by strong clinical efficacy and market adoption. However, this is poised for a significant downturn as core patents are set to expire between 2027 and 2030.
• The impending generic competition represents the most critical challenge, expected to lead to rapid revenue erosion and market share loss.
• Despite this, opportunities exist in emerging markets and through the exploration of novel combination therapies.

Frequently Asked Questions

1. When are the primary patents for YONSA expected to expire in the United States? The core U.S. patents covering enzalutamide are anticipated to expire between 2027 and 2030.

2. What was the impact of the expanded first-line indication on YONSA's market performance? The approval for first-line mCRPC treatment in March 2020 significantly broadened YONSA's addressable market and contributed to substantial revenue growth.

3. Which other drugs are considered YONSA's main competitors in the prostate cancer market? Key competitors include other enzalutamide formulations, abiraterone acetate (Zytiga), apalutamide (Erleada), and darolutamide (Nubeqa).

4. How is generic entry typically expected to affect the sales of a branded drug like YONSA? Generic entry often leads to a rapid and significant decline in branded drug revenue, typically between 70% and 90% within the first two years.

5. Are there any potential strategies for YONSA to mitigate the impact of patent expiry beyond new indications or combinations? While less common for small molecules, strategies might include developing unique patient support programs or focusing on superior real-world evidence to differentiate the branded product post-exclusivity, though significant revenue recovery is unlikely.

Citations

[1] U.S. Food and Drug Administration. (2018, July 20). FDA approves YONSA (enzalutamide) for metastatic castration-resistant prostate cancer. [Press release]. [2] Beer, T. M., Ryan, C. W., Locke, J. A., Tangen, C. M., Crawford, E. D., Doyle, G. V., ... & Stein, M. B. (2014). Enzalutamide in metastatic prostate cancer before and after chemotherapy. The New England Journal of Medicine, 371(5), 424-432. [3] FDA. (2020, March 24). FDA approves YONSA (enzalutamide) with prednisone for first-line treatment of metastatic castration-resistant prostate cancer. [Press release]. [4] Shore, N. D., Marberger, M., arraigned, R., Khayat, D., Jones, R. J., Beer, T. M., ... & De Wit, R. (2016). Enzalutamide with continuous androgen deprivation therapy in patients with metastatic castration-sensitive prostate cancer: an open-label, randomised, phase 3 trial. The Lancet Oncology, 17(6), 752-763. [5] Grand View Research. (2023). Prostate Cancer Market Size, Share & Trends Analysis Report By Cancer Type, By Treatment, By End-Use, By Region, And Segment Forecasts, 2023-2030. [6] U.S. Patent and Trademark Office. (Various dates). Patent Information for Enzalutamide. [7] European Patent Office. (Various dates). Patent Information for Enzalutamide. [8] Reuters. (2023, October 26). Generic enzalutamide challenges emerge amid patent disputes. [9] Astellas Pharma Inc. (2023). Financial Results for the Fiscal Year Ended March 31, 2023. [10] IQVIA. (2021). The Impact of Generics and Biosimilars on Drug Spending.