KORLYM Drug Patent Profile

When do Korlym patents expire, and when can generic versions of Korlym launch?

Korlym is a drug marketed by Corcept Therap and is included in one NDA. There are eighteen patents protecting this drug and one Paragraph IV challenge.

This drug has forty patent family members in twelve countries.

The generic ingredient in KORLYM is mifepristone. There are six drug master file entries for this compound. Four suppliers are listed for this compound. Additional details are available on the mifepristone profile page.

DrugPatentWatch^® Litigation and Generic Entry Outlook for Korlym

A generic version of KORLYM was approved as mifepristone by GENBIOPRO on April 11^th, 2019.

Summary for KORLYM

International Patents:	40
US Patents:	18
Applicants:	1
NDAs:	1
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for KORLYM

Paragraph IV (Patent) Challenges for KORLYM

Tradename	Dosage	Ingredient	Strength	NDA	ANDAs Submitted	Submissiondate
KORLYM	Tablets	mifepristone	300 mg	202107	1	2017-12-15

US Patents and Regulatory Information for KORLYM

KORLYM is protected by eighteen US patents.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Corcept Therap	KORLYM	mifepristone	TABLET;ORAL	202107-001	Feb 17, 2012	AB	RX	Yes	Yes	10,166,243
Corcept Therap	KORLYM	mifepristone	TABLET;ORAL	202107-001	Feb 17, 2012	AB	RX	Yes	Yes	10,006,924
Corcept Therap	KORLYM	mifepristone	TABLET;ORAL	202107-001	Feb 17, 2012	AB	RX	Yes	Yes	9,943,526

International Patents for KORLYM

See the table below for patents covering KORLYM around the world.

Country	Patent Number	Title	Estimated Expiration
Australia	2016305092	Method for differentially diagnosing ACTH-dependent Cushing's syndrome
Canada	2994422	PROCEDE PERMETTANT D'ETABLIR UN DIAGNOSTIC DIFFERENTIEL DU SYNDROME DE CUSHING EN FONCTION DE L'HORMONE ADRENOCORTICOTROPE (ACTH) (METHOD FOR DIFFERENTIALLY DIAGNOSING ACTH-DEPENDENT CUSHING'S SYNDROME)
European Patent Office	3335043	PROCÉDÉ PERMETTANT D'ÉTABLIR UN DIAGNOSTIC DIFFÉRENTIEL DU SYNDROME DE CUSHING EN FONCTION DE L'HORMONE ADRÉNOCORTICOTROPE (ACTH) (METHOD FOR DIFFERENTIALLY DIAGNOSING ACTH-DEPENDENT CUSHING'S SYNDROME)

Last updated: July 22, 2026

KORLYM (mifepristone) Investment Scenario and Patent/Regulatory Fundamentals Analysis: Exclusivity, Generic/Biosimilar Risk, and Revenue Exposure

KORLYM (mifepristone) is a niche endocrine product with a concentrated commercial profile tied to U.S. availability, specialty prescribing, and dosing logistics. The investment case hinges on (1) how long remaining U.S. exclusivity and Orange Book coverage restrict generic entry, (2) whether FDA regulatory status supports sustained growth versus label-limiting safety constraints, and (3) the risk that compendial or off-label mifepristone use erodes growth economics even if formal generic competition is delayed.

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What is KORLYM and what is the current commercial and clinical positioning?

KORLYM is the brand name for mifepristone, an antiprogestin and glucocorticoid receptor antagonist, used in the treatment of endogenous Cushing’s syndrome when surgery is not an option or not expected to be effective, or for patients with persistent or recurrent disease. In practice, KORLYM is a specialty endocrine therapy with patient selection driven by confirmatory diagnostic workups, imaging, comorbidity burden, and safety monitoring.

Core investment implication: cash flows are concentrated in a smaller treated population than large chronic-market endocrine drugs. Revenue durability depends on continued FDA label utilization, real-world adherence to monitoring, and payer coverage stability.

What is the key value proposition behind mifepristone in Cushing’s syndrome?

• Targets symptom burden driven by hypercortisolism via glucocorticoid receptor antagonism.
• Used when standard of care (surgery) is unsuitable or ineffective.
• Requires risk management around adrenal insufficiency and drug interactions.

What are the dominant commercial risks for KORLYM?

• Narrow indication size and slow patient onboarding.
• Off-label prescribing dynamics can blunt brand economics even without approved generic alternatives.
• Specialty channel concentration: pharmacy distribution, REMS-like monitoring practices (if applicable to the product/labeling), and prior authorization friction.

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What patents protect KORLYM (mifepristone) in the U.S., and when do they expire?

A complete, accurate patent landscape requires KORLYM’s Orange Book listings and the specific patent numbers and expiration dates for:

1. the approved drug product,
2. drug substance (if listed),
3. methods of use (if listed).

This analysis cannot be produced without those patent identifiers and their expiry data.

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What is the Orange Book status of KORLYM, and which patents are listed for approval?

This analysis cannot be produced without the Orange Book record for KORLYM, including:

• Applicant/holder listed by FDA,
• Orange Book patent list and patent type (drug substance, product, method of use),
• Patent expiration dates and relevant exclusivity codes.

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When does KORLYM lose exclusivity for generics, and what exclusivity blocks Paragraph IV filings?

This analysis cannot be produced without:

• FDA exclusivity end dates tied to the approval (including new chemical entity, new clinical investigation, and any relevant data exclusivity),
• Orange Book patent expiration timelines and patent-by-patent enforceability.

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How many patents cover KORLYM formulations, and what formulation or dosage-form IP matters for generics?

This analysis cannot be produced without the Orange Book patent list specifying product formulation or dosage form coverage, including:

• strength-specific product patents,
• formulation patents (if listed),
• manufacturing or method-of-use patents.

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What method-of-use patents protect KORLYM in Cushing’s syndrome, and how could they limit generics?

This analysis cannot be produced without Orange Book method-of-use patent numbers and their claim scopes, including:

• patient subpopulations defined by disease status (persistent, recurrent, not surgical),
• dosing regimen claims,
• monitoring or therapeutic effect claims.

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Which companies are challenging KORLYM with generic or biosimilar pathways?

This analysis cannot be produced without filed ANDA-related litigation/notice records (Paragraph IV for small molecules) or any relevant ANDA/DSP activity linked to KORLYM’s Orange Book-listed patents.

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What KORLYM patent litigation affects generic entry in the U.S.?

This analysis cannot be produced without:

• case dockets,
• asserted patent numbers,
• filings of notice of Paragraph IV challenges,
• settlement terms (if any).

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What settlement agreements or consent judgments exist for KORLYM?

This analysis cannot be produced without confirmed settlement or consent judgment documents tied to asserted Orange Book patents for KORLYM.

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What FDA regulatory milestones and label constraints drive KORLYM utilization risk?

This analysis cannot be produced without KORLYM’s current FDA label status details, including:

• approval date and labeling revisions,
• current indications and dosing instructions,
• boxed warnings, contraindications, and monitoring requirements that govern real-world uptake.

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Is KORLYM exposed to biosimilar risk?

KORLYM is a small-molecule drug (mifepristone). Biosimilar frameworks typically apply to biologics, not small molecules. A biosimilar risk assessment still requires confirmation of whether any reference biologic comparisons exist, which is not applicable based on drug class alone. No further patent or regulatory assessment can be provided without FDA pathway details for any “follow-on” versions.

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How does KORLYM compare with competing therapies for endogenous Cushing’s syndrome on IP and commercial defensibility?

A defensible comparison needs:

• competitor drug approvals and their FDA exclusivity/patent timelines,
• class-specific mechanisms (steroidogenesis inhibitors vs receptor antagonists) and payer coverage patterns,
• evidence of real-world utilization and outcomes.

This cannot be completed without competitor patent/exclusivity data.

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Generic entry scenarios for KORLYM: what would likely be the market-impact timeline?

A credible entry model requires:

• remaining Orange Book patent terms,
• likely Paragraph IV likelihood and launch economics (generic pricing, distribution),
• potential 180-day exclusivity triggers and “at-risk” launch constraints.

This cannot be produced without the underlying patent and exclusivity timeline data.

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Manufacturing and IP barriers: what limits generic production of KORLYM?

Barrier analysis requires:

• manufacturing-process patents (if listed),
• stability/particle-size/process claims (if any),
• formulation constraints (if listed),
• any regulatory CMC bottlenecks tied to reference listed changes.

This cannot be produced without the Orange Book listing and any related patent families.

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Key Takeaways

• KORLYM’s investment thesis is driven by U.S. IP and FDA regulatory status rather than by broad-market volume.
• The actionable diligence item for an investor is the Orange Book patent-by-patent table (expiration and enforceability) paired with current label utilization constraints.
• Without KORLYM’s FDA/Orange Book patent listing and exclusivity timeline, patent-duration, generic timing, and litigation/settlement risk cannot be quantified.

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FAQs

1. How do I build a KORLYM generic launch risk model using FDA exclusivity and Orange Book patents?
2. What are the most likely KORLYM patent types (drug substance, product, method of use) that block ANDA entry?
3. What label safety constraints most affect KORLYM real-world prescribing and persistence?
4. How should investors benchmark KORLYM’s specialty-channel economics versus Cushing’s alternatives?
5. What diligence steps determine whether KORLYM is vulnerable to off-label competition?

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References

No sources were cited because KORLYM’s Orange Book and FDA patent/exclusivity records were not provided in the prompt.