DCT

1:13-cv-01212

UCB Inc v. Glenmark Generics Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:13-cv-01212, D. Del., 07/10/2013
  • Venue Allegations: Venue is alleged to be proper in the District of Delaware based on Defendant Glenmark USA being a Delaware corporation and both defendants allegedly conducting business in the district, including developing and selling pharmaceutical products.
  • Core Dispute: Plaintiffs allege that Defendants' filing of Abbreviated New Drug Applications (ANDAs) to market generic versions of the drug Vimpat® constitutes an act of infringement of a patent covering the drug's active ingredient, lacosamide.
  • Technical Context: The technology relates to specific chemical compounds known as enantiomeric amino acid derivatives used as anticonvulsant agents for the treatment of epilepsy.
  • Key Procedural History: The patent-in-suit, RE 38,551, is a reissue of U.S. Patent No. 5,773,475. The complaint states the patent term was extended under 35 U.S.C. § 156, with an expiration date of March 17, 2022. The complaint also outlines a chain of ownership and licensing from the original assignee, Research Corporation Technologies, Inc., to the current marketer, UCB, Inc.

Case Timeline

Date Event
1996-03-15 Priority Date for U.S. Reissued Patent No. RE 38,551
1998-06-30 Issue Date for Original U.S. Patent No. 5,773,475
2004-07-06 Issue Date for U.S. Reissued Patent No. RE 38,551
2008-10-28 FDA Approval Date for Vimpat® Tablets and Intravenous Solution (NDAs 022253 & 022254)
2010-04-20 FDA Approval Date for Vimpat® Oral Solution (NDA 022255)
2013-05-30 Date of Defendant's Notice of Certification Letters for ANDAs 204980 and 205006
2013-07-10 Complaint Filing Date
2022-03-17 Extended Expiration Date for U.S. Reissued Patent No. RE 38,551

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

U.S. Reissued Patent No. RE 38,551 - Anticonvulsant Enantiomeric Amino Acid Derivatives

  • Patent Identification: U.S. Reissued Patent No. RE 38,551, Anticonvulsant Enantiomeric Amino Acid Derivatives, issued July 6, 2004.

The Invention Explained

  • Problem Addressed: The patent's background describes a need for improved anticonvulsant drugs to treat epilepsy. It notes that many existing therapies fail to achieve total seizure control for a significant portion of the patient population and are associated with "disturbing side effects," particularly liver toxicity with long-term (chronic) use (RE 38,551 Patent, col. 2:61-col. 3:7).
  • The Patented Solution: The invention addresses this problem by identifying a specific enantiomer (a type of stereoisomer) of a class of amino acid derivatives that exhibits high anticonvulsant potency with minimal toxicity. The patent discloses that compounds in the "R configuration" are "significantly more efficacious than the corresponding S enantiomer or a racemic mixture thereof" (RE 38,551 Patent, col. 5:1-4). The invention covers the specific R-enantiomer compound, compositions containing it, and methods of using it to treat central nervous system disorders (RE 38,551 Patent, Abstract; col. 3:56-65).
  • Technical Importance: The isolation of a single, more potent, and less toxic enantiomer from a racemic mixture represented a potential therapeutic advance, offering a path to more effective and safer long-term treatment for epilepsy patients (RE 38,551 Patent, col. 23:26-54).

Key Claims at a Glance

  • The complaint alleges infringement of "one or more claims" without specifying them (Compl. ¶36). However, the central dispute concerns the compound lacosamide, which corresponds to independent claim 8.
  • Independent Claim 8:
    • A compound which is (R)-N-Benzyl 2-Acetamido-3-methoxypropionamide.

III. The Accused Instrumentality

Product Identification

  • The accused instrumentalities are Defendant Glenmark USA's proposed generic drug products submitted to the FDA for approval under ANDA No. 204980 (lacosamide oral solution, 10 mg/ml) and ANDA No. 205006 (lacosamide tablets, 50 mg, 100 mg, 150 mg, and 200 mg) (Compl. ¶¶26-28).

Functionality and Market Context

  • The accused products are generic versions of Plaintiffs' branded drug, Vimpat®, which is indicated as adjunctive therapy for treating partial-onset seizures in epilepsy patients (Compl. ¶15). The complaint alleges that Glenmark's ANDA filings seek approval to commercially manufacture and sell these generic products in the United States prior to the expiration of the ’551 patent, which is a statutory act of infringement under the Hatch-Waxman Act (Compl. ¶¶7, 30). The active ingredient in the accused products is alleged to be lacosamide (Compl. ¶35).

IV. Analysis of Infringement Allegations

The complaint’s infringement theory is based on the filing of ANDAs for products whose active ingredient is the compound claimed in the ’551 patent. The complaint provides a 2D chemical structure of lacosamide, the active ingredient at issue (Compl. ¶18).

RE 38,551 Infringement Allegations

Claim Element (from Independent Claim 8) Alleged Infringing Functionality Complaint Citation Patent Citation
The compound which is (R)-N-Benzyl 2-Acetamido-3-methoxypropionamide. The complaint alleges that the active ingredient in Glenmark's proposed ANDA Products is lacosamide, which it identifies chemically as (R)-2-acetamido-N-benzyl-3-methoxypropionamide. ¶18, ¶35 col. 3:58-59
  • Identified Points of Contention:
    • Technical Questions: In this type of pharmaceutical case, where infringement is based on the chemical identity of the active ingredient, the primary dispute is typically over patent validity rather than infringement. The complaint notes that Glenmark's ANDA certification letter asserts the ’551 patent is "invalid and/or will not be infringed" (Compl. ¶32). The infringement analysis itself raises the factual question of whether Glenmark's proposed product formulation contains the exact chemical compound of claim 8.
    • Scope Questions: Claim 8 claims the chemical compound itself. Dependent claim 9, which may be asserted later, adds a purity limitation of "at least 90% (w/w) R stereoisomer" (RE 38,551 Patent, col. 38:39-40). Should this or other dependent claims be asserted, a point of contention may arise regarding the enantiomeric purity of the lacosamide in the accused generic products.

V. Key Claim Terms for Construction

In a case centered on a specific compound claim like claim 8, claim construction disputes are less common than in other technology areas. However, looking at the broader claim set from which claim 8 depends, certain terms may be scrutinized, particularly in the context of validity challenges.

  • The Term: "lower alkoxy" (from independent claim 1)
  • Context and Importance: This term is part of the generic chemical formula in claim 1, which provides the foundation for the specific compound in claim 8. The definition of "lower alkoxy" helps define the scope of the invention and its relationship to prior art. A defendant challenging the patent's validity might argue for a particular construction of this term to bring more prior art into play.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification provides a definition for the related term "lower alkyl" as a group "containing 1-6 carbon atoms which may be straight chained or branched" (RE 38,551 Patent, col. 6:65-68). This could support a reading of "lower alkoxy" that also encompasses a 1-6 carbon chain.
    • Evidence for a Narrower Interpretation: The specification also identifies preferred embodiments, stating that alkoxy groups "more preferably" contain "one to three carbon atoms" and that the "most preferred alkoxy groups are propoxy, isopropoxy, ethoxy and especially methoxy" (RE 38,551 Patent, col. 3:36-39). Parties may argue that such statements limit the term's effective scope to these specific examples.

VI. Other Allegations

  • Indirect Infringement: The complaint does not contain separate counts for indirect infringement. However, it alleges that Glenmark USA's actions were performed with the "cooperation, participation assistant of, and at least in part for the benefit of, Glenmark Ltd." (Compl. ¶37), which could form the basis for later arguments regarding joint or vicarious liability.
  • Willful Infringement: The complaint alleges that Glenmark was "aware of the '551 patent" when it filed its ANDAs (Compl. ¶31). This alleged pre-suit knowledge, evidenced by the requirement to file a Paragraph IV certification against the patent, forms the basis for the willfulness allegation.

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

  • The primary issue in this litigation will almost certainly be one of patent validity. Given that the infringement allegation rests on the straightforward identity of a chemical compound, the case will likely turn on whether claim 8 of the ’551 patent, covering the specific (R)-enantiomer of lacosamide, is invalid as anticipated or obvious in light of prior art, as Glenmark's certification letter suggests (Compl. ¶32).
  • A central evidentiary question will be one of chemical identity and purity. While infringement of claim 8 seems direct, the assertion of dependent claims (such as claim 9) would introduce a factual dispute over whether the enantiomeric purity of Glenmark's proposed generic drug meets the specific percentage thresholds required by those claims.
  • A third area of focus may be on prosecution history. The patent-in-suit is a reissue that also received a patent term extension. This history may give rise to arguments of prosecution history estoppel or disclaimer, creating potential limitations on claim scope that the court will need to resolve.