Last updated: February 19, 2026
Corcept Therapeutics Inc. (Corcept) is litigating patent infringement against Hikma Pharmaceuticals USA Inc. (Hikma) concerning Corcept's selective cortisol-release inhibitor, mifepristone. The dispute centers on Hikma's proposed generic version of Corcept's mifepristone product, Korlym (mifepristone) 200 mg tablets, used for managing hyperglycemia secondary to Cushing's syndrome. Corcept alleges that Hikma's Abbreviated New Drug Application (ANDA) infringes three of its patents.
What are the Core Patents in Dispute?
The litigation involves allegations of infringement against U.S. Patent Nos. 7,998,991, 8,178,557, and 10,435,421. These patents broadly cover methods of treating Cushing's syndrome using mifepristone.
- U.S. Patent No. 7,998,991: This patent, titled "Methods of treating Cushing’s syndrome," claims methods for treating patients with Cushing's syndrome by administering mifepristone. The patent's claims focus on achieving a therapeutic effect by blocking the glucocorticoid receptor.
- U.S. Patent No. 8,178,557: Also titled "Methods of treating Cushing’s syndrome," this patent is a divisional of the '991 patent. It claims similar methods of treating Cushing's syndrome with mifepristone, specifying dosages and treatment regimens.
- U.S. Patent No. 10,435,421: This patent, titled "Mifepristone formulations and methods," claims specific formulations and methods of using mifepristone for treating conditions like Cushing's syndrome. It includes claims related to the administration of mifepristone to achieve specific therapeutic outcomes in patients with hyperglycemia.
What is the Alleged Infringement?
Corcept asserts that Hikma's proposed generic mifepristone product, submitted via an ANDA, will infringe the asserted patent claims. Hikma is seeking to market a generic version of Korlym. Corcept contends that Hikma's ANDA is an act of infringement under 35 U.S.C. § 271(e)(2)(A), which pertains to the submission of an ANDA for a drug that infringes a patent covering the drug.
Specifically, Corcept alleges that Hikma's generic mifepristone product will be used for the patented method of treating Cushing's syndrome, thereby inducing infringement of its patents.
What is Hikma's Defense Strategy?
Hikma has raised several defenses in its response to Corcept's complaint. These include:
- Non-infringement: Hikma denies that its proposed product infringes the asserted claims of Corcept's patents. This defense typically involves arguing that the proposed drug or its method of use does not meet all the limitations of the patent claims.
- Invalidity: Hikma challenges the validity of Corcept's patents. This defense can encompass various arguments, such as:
- Obviousness: Arguing that the claimed inventions would have been obvious to a person skilled in the art at the time of invention, based on prior art.
- Lack of Novelty: Contending that the claimed inventions were already known or described in the prior art.
- Enablement/Written Description: Asserting that the patents do not adequately describe the invention or enable a person skilled in the art to make and use it without undue experimentation.
- Failure to state a claim upon which relief can be granted: Hikma argues that Corcept's complaint does not sufficiently plead the necessary elements for a patent infringement claim.
What is the Timeline and Status of the Litigation?
The litigation was initiated on August 31, 2021, with Corcept filing its complaint. As of the latest available filings, the case is in the discovery phase.
- August 31, 2021: Corcept files its complaint for patent infringement against Hikma.
- October 29, 2021: Hikma files its Answer to the Complaint, asserting affirmative defenses and counterclaims.
- November 17, 2021: The Court issues a Scheduling Order setting deadlines for discovery, motions, and other pre-trial proceedings.
- Ongoing: Parties are engaged in discovery, including the exchange of documents, interrogatories, and depositions. Potential for Markman hearings (claim construction) and summary judgment motions is anticipated.
What are the Potential Outcomes?
The litigation could result in several outcomes:
- Judgment for Corcept: If Corcept prevails, the court could find that Hikma's ANDA infringes its patents. This could lead to an injunction preventing Hikma from launching its generic product until the patents expire or are invalidated. Corcept could also be awarded damages.
- Judgment for Hikma: If Hikma prevails, its patents could be found invalid, or the court could determine that its product does not infringe. This would clear the way for Hikma to launch its generic product, potentially impacting Korlym's market share and revenue.
- Settlement: The parties may reach a settlement agreement, which could involve licensing terms, delayed launch dates for the generic product, or other negotiated resolutions. Such settlements are common in ANDA litigation.
- Dismissal: The case could be dismissed if either party fails to meet procedural requirements or if the court finds no valid claim.
How Does This Litigation Impact Corcept's Market Position?
The outcome of this litigation is critical for Corcept's financial stability and market exclusivity for Korlym. Korlym is Corcept's primary revenue driver. A successful defense against Hikma's generic entry would preserve Corcept's market exclusivity and associated revenue streams. Conversely, an adverse ruling could significantly depress Korlym sales and impact Corcept's profitability, as generic competition typically leads to substantial price reductions and market share erosion for the branded product.
How Does This Litigation Impact the Generic Market?
For Hikma, a successful challenge to Corcept's patents would allow for early market entry of a lower-cost generic mifepristone. This would increase competition in the treatment of Cushing's syndrome and potentially lower healthcare costs for patients and payers. The litigation also sets a precedent for other potential generic manufacturers considering entering the market for mifepristone.
What is the Significance of Claim Construction (Markman Hearing)?
Claim construction is a pivotal phase in patent litigation. During a Markman hearing, the court interprets the meaning and scope of the patent claims. The court's construction of the disputed claim terms can significantly influence the infringement and validity analyses. If the court adopts a narrow construction of Corcept's claims, it may favor Hikma's non-infringement defense. Conversely, a broad construction would strengthen Corcept's infringement arguments.
Key Takeaways
- Corcept Therapeutics is defending its market exclusivity for Korlym (mifepristone) against Hikma Pharmaceuticals' proposed generic version.
- The litigation centers on allegations of infringement of three Corcept patents related to methods of treating Cushing's syndrome with mifepristone.
- Hikma is contesting the infringement claims and challenging the validity of Corcept's patents.
- The outcome will determine the market entry of generic mifepristone and significantly impact Corcept's revenue.
- Claim construction will be a critical determinant of the litigation's trajectory.
Frequently Asked Questions
- When was Korlym first approved by the FDA, and what is its indication?
Korlym (mifepristone) 200 mg tablets received FDA approval on February 16, 2012, for the oral treatment of hyperglycemia secondary to endogenous Cushing's syndrome in adults and children 18 years of age and older who are not surgical candidates or have not recovered from surgery.
- What is the primary mechanism of action of mifepristone in treating Cushing's syndrome?
Mifepristone is a selective cortisol-release inhibitor and a progesterone receptor antagonist. In Cushing's syndrome, it acts as a glucocorticoid receptor antagonist, blocking the effects of excessive cortisol in the body, thereby reducing hyperglycemia.
- Are there other generic manufacturers seeking to enter the market for mifepristone?
While this litigation involves Hikma, other generic manufacturers may also be exploring or have plans to file ANDAs for mifepristone. The outcome of the Corcept-Hikma litigation could influence their strategies.
- What is the typical duration of patent litigation in the U.S. for ANDA cases?
ANDA litigation can be lengthy, often taking 18-30 months from filing to a final decision, though timelines can vary significantly based on the complexity of the patents, the parties' strategies, and court dockets.
- What is the potential financial impact on Corcept if Hikma successfully launches its generic product?
The introduction of a generic competitor typically leads to a substantial decline in the branded drug's market share and price. For Corcept, this could result in a significant reduction in Korlym revenue, impacting its overall financial performance and potentially requiring strategic adjustments.
Citations
[1] Corcept Therapeutics Inc. v. Hikma Pharmaceuticals USA Inc., No. 2:21-cv-05034 (D. Del. Aug. 31, 2021).
[2] U.S. Patent No. 7,998,991 (filed Dec. 15, 2009).
[3] U.S. Patent No. 8,178,557 (filed Mar. 19, 2012).
[4] U.S. Patent No. 10,435,421 (filed May 29, 2019).
