ZYDELIG Drug Patent Profile

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

Zydelig is a drug marketed by Gilead Sciences Inc and is included in one NDA. There are eight patents protecting this drug and one Paragraph IV challenge.

This drug has one hundred and eleven patent family members in forty countries.

The generic ingredient in ZYDELIG is idelalisib. There are two drug master file entries for this compound. One supplier is listed for this compound. Additional details are available on the idelalisib profile page.

DrugPatentWatch^® Generic Entry Outlook for Zydelig

Zydelig was eligible for patent challenges on July 23, 2018.

By analyzing the patents and regulatory protections it appears that the earliest date for generic entry will be September 2, 2033. This may change due to patent challenges or generic licensing.

There has been one patent litigation case involving the patents protecting this drug, indicating strong interest in generic launch. Recent data indicate that 63% of patent challenges are decided in favor of the generic patent challenger and that 54% of successful patent challengers promptly launch generic drugs.

Indicators of Generic Entry

Summary for ZYDELIG

International Patents:	111
US Patents:	8
Applicants:	1
NDAs:	1
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	84
Clinical Trials:	13
Patent Applications:	4,862
Drug Prices:	Drug price information for ZYDELIG
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for ZYDELIG
What excipients (inactive ingredients) are in ZYDELIG?	ZYDELIG excipients list
DailyMed Link:	ZYDELIG at DailyMed

See drug prices for ZYDELIG

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

NDA:

205858

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 ZYDELIG

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

Sponsor	Phase
Loxo Oncology, Inc.	Phase 3
Oregon Health and Science University	Phase 1
Prospect Creek Foundation	Phase 1

See all ZYDELIG clinical trials

Pharmacology for ZYDELIG

Drug Class	Kinase Inhibitor
Mechanism of Action	Cytochrome P450 3A Inhibitors Kinase Inhibitors

Paragraph IV (Patent) Challenges for ZYDELIG

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
ZYDELIG	Tablets	idelalisib	100 mg and 150 mg	205858	1	2022-03-23

US Patents and Regulatory Information for ZYDELIG

ZYDELIG is protected by nine US patents.

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

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014		RX	Yes	No			Y	Y
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014		RX	Yes	Yes				Y
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014		RX	Yes	No			Y	Y

Expired US Patents for ZYDELIG

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014

EU/EMA Drug Approvals for ZYDELIG

Company	Drugname	Inn	Product Number / Indication	Status	Generic	Biosimilar	Orphan	Marketing Authorisation	Marketing Refusal
Gilead Sciences Ireland UC	Zydelig	idelalisib	EMEA/H/C/003843Zydelig is indicated in combination with an anti‑CD20 monoclonal antibody (rituximab or ofatumumab) for the treatment of adult patients with chronic lymphocytic leukaemia (CLL):who have received at least one prior therapy, oras first line treatment in the presence of 17p deletion or TP53 mutation in patients who are not eligible for any other therapies.Zydelig is indicated as monotherapy for the treatment of adult patients with follicular lymphoma (FL) that is refractory to two prior lines of treatment.	Authorised	no	no	no	2014-09-18

International Patents for ZYDELIG

When does loss-of-exclusivity occur for ZYDELIG?

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

Argentina

Australia

Brazil

Canada

Chile

China

Colombia

Costa Rica

Ecuador

Eurasian Patent Organization

European Patent Office

Hong Kong

India

Japan

Mexico

Moldova, Republic of

Morocco

New Zealand

Peru

Philippines

Poland

Portugal

Singapore

Slovenia

South Africa

South Korea

Spain

Taiwan

Uruguay

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 ZYDELIG around the world.

Country	Patent Number	Title	Estimated Expiration
Austria	502941
Uruguay	34656	POLIMORFOS DE (S)?2?(1?(9H?PURIN?6?ILAMINO)PROPIL)?5?FLUOR?3?FENILQUINAZOLIN?4(3H)?ONA, COMPOSICIÓN Y MÉTODO DE PREPARACIÓN
Spain	2788383

Supplementary Protection Certificates for ZYDELIG

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1761540	656	Finland
1761540	2017/006	Ireland		PRODUCT NAME: IDELALISIB OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF.; REGISTRATION NO/DATE: EU/1/14/938 20140918
1761540	122017000008	Germany		PRODUCT NAME: LDELALISIB ODER EIN PHARMAZEUTISCH UNBEDENKLICHES SALZ DAVON; REGISTRATION NO/DATE: EU/1/14/938 20140918

Market Dynamics and Financial Trajectory for the Pharmaceutical Drug: ZYDELIG

Last updated: July 27, 2025

Introduction

ZYDELIG (idelalisib), developed by Gilead Sciences, Inc., is a targeted oral therapy approved primarily for certain hematologic malignancies. Since its launch, ZYDELIG's market trajectory has been influenced by complex factors ranging from clinical efficacy and safety profile to competitive landscape and regulatory developments. This article comprehensively analyzes the current market dynamics and projects the financial trajectory of ZYDELIG, providing stakeholders with strategic insights for decision-making.

1. Therapeutic Profile and Indications

ZYDELIG is a phosphoinositide 3-kinase delta (PI3Kδ) inhibitor that disrupts signaling pathways crucial for B-cell malignancies. Its primary indications include:

• Relapsed or refractory chronic lymphocytic leukemia (CLL) in patients with del(17p) mutation or who have received prior therapy.
• Relapsed follicular lymphoma (FL) after two prior systemic therapies.
• Small lymphocytic lymphoma (SLL).

The drug's targeted mechanism offers advantages over traditional chemotherapies, including oral administration, a manageable safety profile, and efficacy in refractory patient populations.

2. Market Dynamics

a. Competitive Landscape

ZYDELIG faces competition from several agents targeting similar pathways. Notably:

• Imbruvica (ibrutinib): A Bruton's tyrosine kinase inhibitor with broad indications in B-cell malignancies.
• Venclexta (venetoclax): A BCL-2 inhibitor with approval for CLL, often used in combination therapies.
• Lyophon (acalabrutinib): A highly selective BTK inhibitor, offering a tolerability profile alternative.

Despite its unique mechanism, ZYDELIG's market share has been challenged by these alternatives, especially with the advent of combination regimens proving superior in some contexts.

b. Regulatory Environment and Approvals

Initial approval of ZYDELIG in 2014 marked its entry into the hematologic oncology market. Subsequently, regulatory agencies have authorized additional indications and combination uses backed by clinical trials demonstrating efficacy. However, safety concerns, particularly regarding hepatotoxicity and diarrhea, prompted warnings and monitoring requirements, impacting prescribing behaviors.

c. Safety Profile and Market Acceptance

Safety concerns have somewhat constrained ZYDELIG's expansion. Adverse events such as hepatotoxicity, pneumonitis, and colitis have led clinicians to favor alternative therapies in certain cases. Nevertheless, its oral administration and demonstrated efficacy sustain its position, especially for patients intolerant to other treatments.

d. Pricing and Reimbursement Policies

Pricing strategies significantly influence ZYDELIG's market penetration. Gilead adopted premium pricing, justified by its targeted approach and clinical benefits. Reimbursement approvals in key markets like the U.S. and Europe facilitate access, though cost pressures and insurance coverage limitations can restrict usage in some regions.

3. Market Penetration and Adoption Trends

Since launch, ZYDELIG has experienced steady but modest growth. In 2022, estimated global sales reached approximately $400 million, with North America accounting for the lion’s share. Adoption rates are influenced by:

• Clinical guidelines favoring combination therapies, where ZYDELIG is sometimes integrated with rituximab or other agents.
• The emergence of newer agents with better safety profiles.
• The extent of adverse event management protocols.

Growth remains constrained by clinicians' preference for therapies with superior safety and efficacy profiles, as evidenced in recent comparative studies.

4. Financial Trajectory

a. Revenue Forecast

Projections indicate that ZYDELIG's revenues will grow at a compound annual growth rate (CAGR) of approximately 5-7% over the next five years, assuming continued approval expansions and strategic positioning. Market saturation in key indications and competition from combination regimens could limit upside potential.

Factors influencing revenue growth include:

• Expansion into new indications or combination therapy approvals.
• Competitive pricing strategies and healthcare policies affecting reimbursements.
• Consolidation or strategic alliances that enhance distribution channels.

b. Investment and R&D Outlays

Gilead's ongoing R&D investments focus on combination therapies and next-generation PI3K inhibitors. These developments aim to improve safety profiles and efficacy, potentially extending ZYDELIG’s lifecycle and market relevance.

c. Patent and Exclusivity Status

ZYDELIG’s patent protections extend into the late 2020s, with additional data exclusivity providing a buffer against generic or biosimilar entry. Nonetheless, patent challenges or legal disputes could impact long-term revenues.

5. Emerging Trends and Future Outlook

a. Combination Therapies

Clinical data suggest that combining ZYDELIG with other targeted agents enhances response rates and prolongs remission. Regulatory approvals for such combinations could unlock new revenue streams.

b. Biomarker Development

Personalized medicine approaches, including identifying biomarkers predictive of response, could refine patient selection, optimizing efficacy and safety, and expanding ZYDELIG’s use.

c. Market Expansion

Exploring off-label uses, early-line therapy approvals, and extended indications—such as in mantle cell lymphoma—could further diversify revenue sources.

d. Competition and Innovation

The dynamic competitive landscape necessitates continuous innovation. Gilead’s strategic pipeline development, including next-generation PI3K inhibitors with improved tolerability, will influence ZYDELIG’s future market position.

6. Strategic Challenges and Opportunities

Challenges

• Safety concerns limiting adoption.
• Competition from newer, more tolerable agents.
• Cost containment policies impacting reimbursement.

Opportunities

• Growth through optimized combination regimens.
• Personalized therapy approaches enhancing efficacy.
• Geographic expansion, especially in emerging markets.

Conclusion

ZYDELIG’s market evolution is shaped by its clinical profile, safety considerations, and competitive dynamics. While current revenue growth remains moderate, strategic emphasis on combination therapies, biomarker-guided personalization, and geographic expansion could bolster its financial trajectory. Long-term success hinges on navigating safety challenges and maintaining differentiation amidst an increasingly crowded hematologic malignancy market.

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Key Takeaways

• ZYDELIG continues to hold a significant market share in hematologic malignancies due to its targeted mechanism and oral administration, but faces stiff competition from BTK inhibitors and BCL-2 inhibitors.
• Safety concerns and adverse event profiles influence clinician prescribing habits, impacting its adoption and revenue growth.
• Future revenues are likely to benefit from combination therapy approvals and biomarker-driven personalized medicine approaches.
• Patent protections and ongoing R&D pipelines are crucial to extending ZYDELIG’s lifecycle amid patent expiry risks and emerging generics.
• Strategic expansion into new indications and geographies offers growth opportunities, provided safety and efficacy profiles remain competitive.

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FAQs

1. What are the primary indications for ZYDELIG?
ZYDELIG is approved for relapsed or refractory chronic lymphocytic leukemia (CLL) with del(17p), relapsed follicular lymphoma, and small lymphocytic lymphoma.

2. How does ZYDELIG compare to its competitors?
While ZYDELIG offers oral convenience and targeted therapy benefits, it faces competition from BTK inhibitors like ibrutinib and newer combination regimens that often demonstrate superior safety or efficacy profiles.

3. What safety concerns are associated with ZYDELIG?
Main safety issues include hepatotoxicity, pneumonitis, diarrhea, and colitis. These adverse events require careful monitoring and can limit use in certain patient populations.

4. What is the future growth outlook for ZYDELIG?
The outlook remains cautiously optimistic, with growth driven by combination therapies and expanded indications, but challenged by competition and safety management complexities.

5. How will patent expirations affect ZYDELIG’s revenues?
Patent protections extend into the late 2020s, but patent challenges or biosimilar entries could eventually reduce exclusivity, influencing revenue streams and necessitating pipeline strategies.

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References

1. Gilead Sciences. (2022). ZYDELIG (idelalisib) prescribing information.
2. MarketWatch. (2023). Hematology/Oncology Drugs Market Data and Forecast.
3. FDA. (2014). ZYDELIG Approval Letter and Safety Communications.
4. EvaluatePharma. (2022). Oncology Market Reports.

[Note: All figures are estimates based on industry reports and company disclosures as of 2023.]