Corcept Therap Inc v. Teva Pharma USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Corcept Therapeutics, Inc. (Delaware)
  • Defendant: Teva Pharmaceuticals USA, Inc. (Delaware) and Teva Pharmaceuticals Industries Ltd. (Israel)
  • Plaintiff’s Counsel: Saul Ewing LLP
• Case Identification: 1:23-cv-01505, D.N.J., 03/17/2023
• Venue Allegations: Plaintiff alleges venue is proper in the District of New Jersey because Defendant Teva USA is headquartered in Parsippany, New Jersey, has purposefully availed itself of the forum, and will target the district for sale of the accused generic drug product.
• Core Dispute: Plaintiff alleges that Defendants’ filing of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff’s KORLYM® (mifepristone) drug product constitutes an act of infringement of patents covering methods of administering the drug.
• Technical Context: The technology concerns pharmaceutical methods for improving the safety and efficacy of mifepristone, a glucocorticoid receptor modulator used to treat hyperglycemia in patients with Cushing's syndrome.
• Key Procedural History: The action arises under the Hatch-Waxman Act, triggered by Teva’s submission of ANDA No. 211436 to the FDA. The complaint notes that Teva began sending Paragraph IV Certification notice letters to Corcept regarding its intent to market a generic version of KORLYM® no earlier than January 31, 2018, which may be relevant to allegations of knowledge for indirect infringement.

Case Timeline

Date	Event
2011-11-18	’801 Patent Priority Date
2017-03-01	’800 Patent Priority Date
2018-01-31	Teva sends first Paragraph IV Certification notice letter (earliest date)
2020-11-24	’800 Patent Issued
2020-11-24	’801 Patent Issued
2023-03-17	Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 10,842,800 - “Concomitant administration of glucocorticoid receptor modulators and CYP3A inhibitors”

The Invention Explained

• Problem Addressed: The patent addresses the risk of increased toxicity when multiple drugs are administered concurrently ('800 Patent, col. 3:15-32). Specifically, drugs that inhibit the CYP3A enzyme system, such as ketoconazole, can cause other drugs to accumulate to dangerous levels in the body, and are themselves associated with risks like liver damage ('800 Patent, col. 2:41-54).
• The Patented Solution: The invention is based on the discovery that a glucocorticoid receptor antagonist (GRA) like mifepristone can be safely and effectively co-administered with a strong CYP3A inhibitor ('800 Patent, col. 4:1-14). The patent discloses that this combination does not produce the large, expected increase in mifepristone plasma levels, allowing for the therapeutic benefits of both drugs without a corresponding increase in toxicity and potentially enabling a reduced dose of mifepristone ('800 Patent, Abstract; col. 4:26-35).
• Technical Importance: This approach provides a method for patients to receive the benefits of both a GRA and a CYP3A inhibitor, a combination that medical practitioners might otherwise avoid due to the risk of drug-drug interaction toxicity ('800 Patent, col. 3:27-32).

Key Claims at a Glance

• The complaint asserts infringement of one or more claims (Compl. ¶39). Independent claim 1 is representative:
  • A method of controlling hyperglycemia secondary to hypercortisolism in a patient with endogenous Cushing's syndrome.
  • The patient is taking an original once-daily dose of 1200 mg/day of mifepristone.
  • The method comprises reducing the original dose to an adjusted once-daily dose of 900 mg/day of mifepristone.
  • The method further comprises administering the adjusted dose of mifepristone and a strong CYP3A inhibitor to the patient.
• The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 10,842,801 - “Optimizing Mifepristone Absorption”

The Invention Explained

• Problem Addressed: The patent describes the "food effect," where oral administration of a drug can result in widely varying plasma concentrations among patients ('801 Patent, col. 1:14-23). This variability can lead to some patients not receiving an efficacious dose of mifepristone ('801 Patent, col. 1:39-42).
• The Patented Solution: The invention provides a method to increase and normalize the absorption of mifepristone by administering the drug within a short time after a patient consumes a meal ('801 Patent, col. 2:48-52). This method is disclosed to alter the drug's pharmacokinetics by increasing its maximum plasma concentration (Cmax) and the total drug exposure (area under the curve, or AUC) compared to administration in a fasted state, thereby improving its therapeutic effect ('801 Patent, Abstract).
• Technical Importance: This method offers a way to overcome patient-to-patient variability in drug absorption, potentially making mifepristone therapy effective for a broader patient population ('801 Patent, col. 1:42-47).

Key Claims at a Glance

• The complaint asserts infringement of one or more claims (Compl. ¶47). Independent claim 1 is representative:
  • A method of improving absorption of mifepristone in a patient suffering from Cushing's Syndrome.
  • The method comprises administering to the patient for at least 7 days an oral dose of 900 mg/day mifepristone.
  • The dose is administered within about 30 minutes after consuming a meal.
  • This administration results in the pharmacokinetics being altered such that the AUC increases by at least 44% compared to administration without food.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The accused instrumentality is "Teva's Proposed Product," a generic version of Corcept's 300 mg mifepristone drug product, for which Teva is seeking FDA approval via ANDA No. 211436 (Compl. ¶¶1, 28).

Functionality and Market Context

• The complaint alleges Teva's Proposed Product is a generic equivalent to Corcept's KORLYM®, which is an FDA-approved medication for treating hyperglycemia secondary to hypercortisolism in certain adult patients with endogenous Cushing's syndrome (Compl. ¶¶1, 11). The act of infringement alleged is Teva's filing of the ANDA to market this generic drug prior to the expiration of the patents-in-suit (Compl. ¶¶39, 47). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint alleges infringement under 35 U.S.C. § 271(e)(2)(A), where the filing of an ANDA for a drug claimed in a patent is a statutory act of infringement (Compl. ¶¶39, 47). The infringement theory suggests that the proposed labeling for Teva's product will instruct medical providers and patients to use the generic mifepristone in a manner that directly practices the methods claimed in the patents-in-suit.

’800 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method of controlling hyperglycemia secondary to hypercortisolism in a patient with endogenous Cushing's syndrome, said patient taking an original once-daily dose of 1200 mg per day of mifepristone...	Teva's proposed product is a generic version of mifepristone intended for the same patient population, and its proposed label will allegedly instruct its use for this condition.	¶¶1, 11, 39	col. 56:28-39
...the method comprising the steps of: reducing the original once-daily dose to an adjusted once-daily dose of 900 milligrams (mg) per day of mifepristone...	Teva's proposed label will allegedly instruct or encourage physicians to dose-reduce Teva's generic mifepristone from 1200 mg to 900 mg when administered with a CYP3A inhibitor.	¶¶39, 42	col. 56:32-35
...and administering the adjusted once-daily dose of 900 mg per day of mifepristone and a strong CYP3A inhibitor to the patient...	Teva's proposed label will allegedly instruct co-administration of its generic mifepristone at the 900 mg/day dose with a strong CYP3A inhibitor.	¶¶39, 42	col. 56:35-39

• Identified Points of Contention:
  • Scope Questions: A central question may be what constitutes "a strong CYP3A inhibitor" as defined by the patent. The patent provides a list of examples, and disputes may arise if Teva's proposed label recommends co-administration with an inhibitor not explicitly listed ('800 Patent, col. 56:40-48).
  • Technical Questions: A key factual question for the court will be the specific language contained in the proposed label for Teva's generic product. The case will depend on whether those instructions direct users to reduce the mifepristone dosage to 900 mg/day specifically when co-administering it with a strong CYP3A inhibitor, as required by the claim.

’801 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method of improving absorption of mifepristone in a patient suffering from Cushing's Syndrome...	Teva's proposed product is a generic mifepristone intended for patients with Cushing's Syndrome, and its use as instructed will allegedly practice the patented method of improving absorption.	¶¶1, 11, 47	col. 66:1-13
...comprising administering to the patient for at least 7 days an oral dose of mifepristone of 900 mg per day within about 30 minutes after consuming a meal...	Teva's proposed label will allegedly instruct patients to take a 900 mg daily dose of its generic mifepristone within 30 minutes of eating a meal.	¶¶47, 50	col. 66:2-6
...such that the pharmacokinetics of mifepristone absorption are altered by ... increasing the area under the curve (AUC) as compared to the ... fasted state ... said increase in AUC being at least 44%...	The administration of Teva's product according to the alleged label instructions will necessarily result in the claimed pharmacokinetic alteration (at least a 44% increase in AUC).	¶¶47, 50	col. 66:6-13

• Identified Points of Contention:
  • Scope Questions: The definition of "meal" could become a point of contention. The patent specification references FDA guidelines for food-effect studies, which may inform the term's construction ('801 Patent, col. 3:21-41).
  • Technical Questions: As with the ’800 patent, the infringement analysis will turn on the precise instructions in Teva's proposed label. The question will be whether the label directs administration of a 900 mg/day dose within 30 minutes of a meal for at least 7 days, thereby meeting the claim limitations. A second factual question is whether Teva can demonstrate that following such instructions does not result in the claimed 44% AUC increase.

V. Key Claim Terms for Construction

• The Term: "a strong CYP3A inhibitor" (’800 Patent, Claim 1)

• Context and Importance: This term is critical because it defines the scope of drug combinations covered by the method claim. The infringement analysis depends entirely on whether the drug co-administered with mifepristone falls within this definition. Practitioners may focus on this term because Teva could argue its proposed label only contemplates co-administration with drugs that are not "strong" CYP3A inhibitors.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: Claim 1 itself recites "a strong CYP3A inhibitor," a general functional class. Claim 2, a dependent claim, provides a specific list ("ketoconazole, itraconazole, nefazodone..."), suggesting the independent claim is not limited to that list under the doctrine of claim differentiation.
  • Evidence for a Narrower Interpretation: The specification states that "strong CYP3A inhibitors" are defined by the FDA as those expected to "increase the AUC of other drugs by greater than five-fold" ('800 Patent, col. 12:15-18). A party might argue the term is limited to drugs meeting this specific FDA criterion.

• The Term: "within about 30 minutes after consuming a meal" (’801 Patent, Claim 1)

• Context and Importance: This temporal limitation is a core element of the claimed method. Infringement requires administration in this specific post-meal window. Practitioners may focus on this term because Teva's proposed label might provide more general instructions (e.g., "take with food") that do not meet the specificity of "within about 30 minutes after."

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The use of "about" suggests the 30-minute mark is not a rigid cutoff and encompasses a reasonable range around that time. The specification describes the method more broadly as "within 1 hour of consuming a meal" ('801 Patent, col. 2:50-51), which may support a more flexible reading of "about 30 minutes."
  • Evidence for a Narrower Interpretation: The claim explicitly recites "about 30 minutes," which is more specific than the "1 hour" mentioned in the detailed description. A party could argue that the claim language itself provides the primary definition and that "about 30 minutes" cannot be expanded to mean a full hour.

VI. Other Allegations

• Indirect Infringement: For both the ’800 and ’801 patents, the complaint alleges induced infringement under 35 U.S.C. § 271(b) (Compl. ¶¶42, 50). The factual basis for inducement is the allegation that Teva will, through its product labeling and instructions, intentionally encourage and instruct physicians and patients to perform the steps of the claimed methods. The complaint alleges Teva has knowledge of the patents based on a series of notice letters sent to Corcept (Compl. ¶¶29-35).
• Willful Infringement: The complaint does not contain an explicit count for "willful infringement."

VII. Analyst’s Conclusion: Key Questions for the Case

This case appears to center on the specific instructions for use that Teva has submitted to the FDA in its ANDA filing. The key questions for the court will likely be:

1. A core issue will be one of "instructional equivalence": Does the language in Teva's proposed product label actively instruct or encourage medical professionals and patients to perform the specific, multi-step methods recited in the asserted claims of the ’800 and ’801 patents? This will be a factual determination based on the contents of the ANDA.
2. A second issue will be one of "definitional scope": For the ’800 patent, can the term "strong CYP3A inhibitor" be construed to cover all drugs that Teva's label might contemplate for co-administration with its generic product? For the ’801 patent, can the phrase "within about 30 minutes after consuming a meal" be read to cover more general "take with food" instructions, should Teva's label contain such language?