Idelalisib - Generic Drug Details

What are the generic sources for idelalisib and what is the scope of freedom to operate?

Idelalisib is the generic ingredient in one branded drug marketed by Gilead Sciences Inc and is included in one NDA. There are eight patents protecting this compound. Additional information is available in the individual branded drug profile pages.

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

There are two drug master file entries for idelalisib. One supplier is listed for this compound.

Summary for idelalisib

International Patents:	111
US Patents:	8
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	2
Finished Product Suppliers / Packagers:	1
Raw Ingredient (Bulk) Api Vendors:	106
Clinical Trials:	65
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for idelalisib
What excipients (inactive ingredients) are in idelalisib?	idelalisib excipients list
DailyMed Link:	idelalisib at DailyMed

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

Constraining patent/regulatory exclusivity:

9,469,643

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 idelalisib

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

Sponsor	Phase
Eli Lilly and Company	PHASE4
Dizal (Jiangsu) Pharmaceutical Co., Ltd.	PHASE3
BeiGene	PHASE3

See all idelalisib clinical trials

Pharmacology for idelalisib

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

Anatomical Therapeutic Chemical (ATC) Classes for idelalisib

L01EM	Phosphatidylinositol-3-kinase (Pi3K) inhibitors
L01E	PROTEIN KINASE INHIBITORS
L01	ANTINEOPLASTIC AGENTS
L	Antineoplastic and immunomodulating agents

Paragraph IV (Patent) Challenges for IDELALISIB

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 idelalisib

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	205858-002	Jul 23, 2014		RX	Yes	Yes	9,492,449
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014		RX	Yes	Yes	9,149,477
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014		RX	Yes	No	9,469,643			Y
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014		RX	Yes	No	8,865,730		Y	Y

Expired US Patents for idelalisib

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	Patent No.	Patent Expiration
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014	6,800,620
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-002	Jul 23, 2014	8,138,195
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014	8,637,533
Gilead Sciences Inc	ZYDELIG	idelalisib	TABLET;ORAL	205858-001	Jul 23, 2014	RE44638

EU/EMA Drug Approvals for idelalisib

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 idelalisib

Country	Patent Number	Title	Estimated Expiration
Netherlands	300867
Lithuania	C1761540
Japan	2017008088	血液学的な悪性疾患のための療法 (THERAPIES FOR HEMATOLOGIC MALIGNANCIES)
Lithuania	1761540

Supplementary Protection Certificates for idelalisib

Patent Number	Supplementary Protection Certificate	SPC Country	SPC Expiration	SPC Description
1761540	PA2017004,C1761540	Lithuania		PRODUCT NAME: IDELALISIBAS ARBA FARMACINIU POZIURIU PRIIMTINA JO DRUSKA; REGISTRATION NO/DATE: EU/1/14/938 20140918
1761540	132017000031007	Italy		PRODUCT NAME: IDELALISIB O UN SUO SALE FARMACEUTICAMENTE ACCETTABILE(ZYDELIG); AUTHORISATION NUMBER(S) AND DATE(S): EU/1/14/938, 20140919
1761540	CR 2017 00007	Denmark		PRODUCT NAME: IDELALISIB ELLER ET FARMACEUTISK ACCEPTABELT SALT DERAF; REG. NO/DATE: EU/1/14/938 20140919
1761540	LUC00005	Luxembourg		PRODUCT NAME: IDELALISIB OU UN SEL PHARMACEUTIQUEMENT ACCEPTABLE DE CELUI-CI; AUTHORISATION NUMBER AND DATE: EU/1/14/938 20140919

Market Dynamics and Financial Trajectory for the Pharmaceutical Drug: Idelalisib

Last updated: July 27, 2025

---

Introduction

Idelalisib, marketed under the brand name Zydelig, is an oral kinase inhibitor developed by Gilead Sciences for the treatment of hematological malignancies, particularly chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), follicular lymphoma (FL), and marginal zone lymphoma (MZL). Approved by the U.S. Food and Drug Administration (FDA) in 2014, idelalisib has since carved a niche within targeted oncology therapies. This report analyzes the compound's market dynamics and financial trajectory, offering insights into its commercial performance, competitive position, and future prospects within the evolving oncology landscape.

---

Market Landscape and Therapeutic Positioning

Market Demand Drivers

The global hematological oncology market experienced robust growth, driven chiefly by increasing incidence rates of CLL and FL, aging populations, and a shift towards targeted therapies. The global leukemia market alone is projected to reach over $13 billion by 2027, with targeted therapies accounting for a significant share due to their improved safety and efficacy profiles [1].

Idelalisib’s mechanism of action as a PI3K delta inhibitor aligns with current trends toward precision medicine, notably targeting pathways critical for malignant cell survival. Its oral administration favors patient compliance, positioning the drug well within outpatient treatment paradigms. However, competition from other targeted agents such as ibrutinib and venetoclax directly impacts its market share.

Competitive Landscape

Idelalisib faces competition from various agents:

• Ibrutinib (Imbruvica): A BTK inhibitor with superior efficacy and safety data, capturing a substantial share since its approval in 2013.
• Venetoclax (Venclyxto): A BCL-2 inhibitor with demonstrated efficacy in CLL, often used in combination with anti-CD20 antibodies.
• Obinutuzumab (Gazyva): A monoclonal antibody supplementing chemotherapy, used in combination therapies [2].

While idelalisib initially led the targeted therapy segment, its position has been compromised by these newer, more tolerable options with superior efficacy profiles.

---

Market Performance and Commercial Dynamics

Sales Trajectory

Gilead’s disclosures indicate that idelalisib’s sales peaked approximately between 2015 and 2017, with annual revenues exceeding $300 million worldwide. However, subsequent years saw a decline, attributable to:

• Efficacy and Safety Concerns: Notable adverse effects such as hepatotoxicity and severe diarrhea led to adverse event-related label warnings, limiting its use.
• Market Competition: The approval and rapid uptake of competitor agents reduced idelalisib’s share.
• Regulatory Challenges: Some markets restricted or limited its approval, narrowing its global footprint.

Pricing Strategy

Idelalisib’s pricing aligns with other targeted oncology treatments—initially premium, with ongoing negotiations, especially in cost-conscious markets. The drug’s cost-effectiveness is often debated, given its adverse effect profile and diminishing selectivity compared to newer agents.

Regulatory and Commercial Adjustments

Amidst declining sales, Gilead shifted focus toward combination regimens and expanded indications to sustain revenue streams. However, the market’s saturation and evolving standards of care have constrained growth prospects. Gilead’s strategic investments now favor next-generation PI3K inhibitors with improved safety profiles.

---

Recent Developments and Future Outlook

Pipeline and Indications Expansion

Current research explores combinations of idelalisib with other targeted agents, such as rituximab or venetoclax, aiming to enhance efficacy and safety. Additionally, investigational studies are examining its utility in other hematological malignancies and autoimmune diseases. Despite these efforts, regulatory hurdles and competition temper the commercial outlook.

Emerging Market Dynamics

Emerging markets exhibit growing demand for targeted therapies due to expanding healthcare infrastructure, but pricing pressures and local regulatory landscapes limit rapid uptake. Reimbursement challenges and patient access programs significantly influence market penetration.

Impact of Precision Medicine Trends

The increasing adoption of personalized treatment regimens underscores a broader shift towards therapies with manageable safety profiles and improved survival benefits. This trend favors novel agents over existing drugs like idelalisib unless they demonstrate clear therapeutic advantages.

Long-Term Financial Trajectory

Given the competitive landscape, idelalisib’s revenues are anticipated to decline steadily over the next five years unless repositioned through novel combination strategies or extended indications. Gilead’s focus may shift toward pipeline candidates or next-generation kinase inhibitors with better tolerability and efficacy profiles.

---

Regulatory Factors and Market Risks

Key regulatory factors influencing idelalisib’s market include:

• Safety Warnings: The FDA’s black box warning and EH-associated adverse events curtail its use.
• Labeling and Indications: Restrictions on use in specific patient populations narrow market scope.
• Generic Competition: Pending patent expirations may introduce biosimilars or generics, intensifying price competition.

Market risks also include:

• Adverse Safety Profile: Leading to off-label restrictions and reduced prescriber confidence.
• Market Saturation: An influx of superior agents diminishes potential growth.
• Pricing Pressures: Heightened in both developed and emerging markets, impacting margins.

---

Conclusion

Idelalisib’s journey exemplifies the challenges faced by targeted therapies in a rapidly evolving oncology market. Its initial promise was undermined by safety concerns and stiff competition from more efficacious and better-tolerated agents. While current revenues are declining, strategic combination therapies and ongoing research could salvage its relevance. Nevertheless, Gilead’s investment corroborates the importance of continual innovation within targeted kinase inhibitor development.

---

Key Takeaways

• Market Decline: Idelalisib’s revenues peaked early and are now diminishing due to safety issues and competition.
• Competitive Pressure: Ibrutinib and venetoclax dominate the hematological malignancy market, limiting idelalisib’s growth.
• Strategic Shift Needed: Repositioning through combination therapies or pipeline advancement is essential.
• Regulatory Challenges: Safety warnings significantly impact prescriber adoption.
• Future Outlook: Steady decline expected unless novel formulations or indications emerge.

---

FAQs

1. What are the primary therapeutic indications for idelalisib?
Idelalisib is mainly approved for relapsed/refractory CLL, SLL, follicular lymphoma, and marginal zone lymphoma, often in patients unsuitable for chemotherapy.

2. How does idelalisib compare to other targeted therapies?
While initially promising, idelalisib is challenged by its safety profile and limited efficacy compared to newer agents like ibrutinib and venetoclax, which offer improved tolerability and survival benefits.

3. What are the main safety concerns associated with idelalisib?
Serious adverse effects include hepatotoxicity, diarrhea, colitis, pneumonitis, and infections, leading to black box warnings and restricted use.

4. What strategies could prolong idelalisib’s market relevance?
Combining idelalisib with other agents, developing next-generation inhibitors, or expanding indications through clinical trials could sustain its market presence.

5. What is the outlook for idelalisib’s commercial future?
Absent significant repositioning, sales are expected to decline sharply, with the product gradually losing market share to more advanced therapies in the hematology sector.

---

References

[1] MarketWatch. "Global Leukemia Therapeutics Market Size, Forecast till 2027,” March 2022.
[2] National Cancer Institute. "Targeted Therapy for Blood Cancers," 2021.