UCB Inc v. Hetero USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: UCB, Inc. (Delaware); UCB BioPharma SPRL (Belgium); Research Corporation Technologies, Inc. (Delaware); Harris FRC Corporation (Delaware)
  • Defendant: Hetero USA Inc. (Delaware); Hetero Labs Limited (India)
  • Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP
• Case Identification: 1:16-cv-00452, D. Del., 06/17/2016
• Venue Allegations: Venue is alleged to be proper in the District of Delaware based on Defendant Hetero USA Inc. being a Delaware corporation and both Defendants having previously submitted to personal jurisdiction in the district in a prior case involving the same patent and Abbreviated New Drug Application (ANDA).
• Core Dispute: Plaintiffs allege that Defendants' filing of an ANDA to market generic lacosamide tablets constitutes an act of infringement of a reissued patent covering the lacosamide compound and its use for treating central nervous system disorders.
• Technical Context: The technology concerns a specific stereoisomer of a functionalized amino acid derivative, known as lacosamide, which is the active ingredient in the anti-epileptic drug Vimpat®.
• Key Procedural History: The complaint details a significant litigation history between the parties over the same patent and ANDA. In a prior case (C.A. No. 13-1213-LPS), Hetero allegedly stipulated that its generic product would infringe the asserted claims. Hetero later amended its ANDA to state it would not seek approval before patent expiration and was dismissed from that suit. The current lawsuit was triggered after Hetero allegedly reversed its position months later and submitted a new ANDA certification asserting the patent is invalid or not infringed. A Markman claim construction hearing was held in the prior consolidated litigation.

Case Timeline

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

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 section describes a need for improved anticonvulsant drugs, noting that a significant portion of the epileptic population is poorly managed by existing therapies, which often cause "disturbing side effects" and can have liver toxicity associated with long-term use ('551 Patent, col. 2:61-col. 3:7).
• The Patented Solution: The invention discloses a class of functionalized amino acid derivatives, and specifically claims compounds in the "R configuration," which are asserted to be highly effective anticonvulsants ('551 Patent, col. 3:63-col. 4:14). The specification states that these R-isomers are "significantly more efficacious" than their S-isomer counterparts or racemic mixtures, and that they exhibit minimal neurological and organ toxicity, making them suitable for chronic administration ('551 Patent, col. 5:1-4; col. 3:56-62).
• Technical Importance: The invention's focus on a specific stereoisomer (the R-isomer) represented a more targeted approach to anticonvulsant therapy, suggesting the potential for improved efficacy and a better safety profile compared to mixtures of isomers ('551 Patent, col. 5:1-4).

Key Claims at a Glance

• The complaint asserts infringement of at least claims 9, 10, and 13 and reserves the right to assert others (Compl. ¶43). The asserted claims depend from independent claims 1 and 11.
• Independent Claim 1 (Compound):
  • A compound in the R configuration
  • having a specific chemical structure shown in the patent
  • wherein "Ar" is an unsubstituted or halo-substituted phenyl group
  • "Q" is lower alkoxy
  • "Q₁" is methyl
• Independent Claim 10 (Composition):
  • A therapeutic composition
  • comprising an "anticonvulsant effective amount" of a compound from claims 1-9
  • and a "pharmaceutical carrier"
• Independent Claim 11 (Method of Use):
  • A method of treating central nervous system disorders in an animal
  • by administering an "anticonvulsant effective amount" of a compound from claims 1-9

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are "Hetero USA's ANDA Products," which are generic lacosamide tablets in 50 mg, 100 mg, 150 mg, and 200 mg dosage forms for which Hetero seeks FDA approval via ANDA No. 204787 (Compl. ¶¶ 27, 28).

Functionality and Market Context

• The complaint alleges that the active ingredient in the accused products is lacosamide (Compl. ¶42). The products are generic versions of Plaintiffs' Vimpat® tablets, which are indicated for treating partial-onset seizures in people with epilepsy (Compl. ¶¶ 15, 27). The filing of the ANDA itself is the statutorily defined act of infringement under 35 U.S.C. § 271(e)(2), signifying an intent to commercially manufacture, use, and sell the generic product in the United States upon approval (Compl. ¶¶ 29-30). The complaint provides the chemical structure of lacosamide, the compound at issue. (Compl. ¶18).

IV. Analysis of Infringement Allegations

RE 38,551 Infringement Allegations

Identified Points of Contention

• Scope Questions: The complaint alleges that in prior litigation, Hetero stipulated that its ANDA products "will infringe claims 9, 10, and 13 of the '551 patent" (Compl. ¶36). A central question for the court may be whether Defendant can proffer a viable non-infringement argument after previously conceding the issue for the same product and patent. The dispute will likely focus on Defendant's renewed assertion of invalidity (Compl. ¶40).
• Technical Questions: As infringement was allegedly stipulated previously, the primary technical dispute is likely to be patent validity rather than a mismatch between the claims and the accused product. The complaint alleges that Hetero's 2016 notice letter does not assert any new bases for invalidity beyond those raised in the earlier litigation (Compl. ¶41). A key question will be whether these invalidity challenges (e.g., based on obviousness or lack of written description) can overcome the patent's presumption of validity.

V. Key Claim Terms for Construction

The complaint notes that the court in a prior, consolidated case held a Markman hearing and issued a claim construction opinion (Compl. ¶35). While the constructions are not provided in the complaint, certain terms are central to the patent.

• The Term: "R configuration" / "substantially enantiomerically pure"
• Context and Importance: The patent's core assertion is the superior efficacy of the R-isomer of the claimed compound compared to the S-isomer or a racemic mixture ('551 Patent, col. 5:1-4). Therefore, the scope of the claims hinges on the required degree of stereochemical purity. Practitioners may focus on this concept because it defines the threshold at which the presence of the S-isomer might place a composition outside the scope of the claims.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification provides specific, non-absolute purity levels, stating it is "more preferred that the compounds...contain at least 90% (w/w) R stereoisomer, and most preferably greater than about 95% (w/w) in the R stereoisomer" ('551 Patent, col. 5:14-17). This language could support a construction that does not require 100% purity.
  • Evidence for a Narrower Interpretation: The abstract and detailed description repeatedly frame the invention in terms of the specific "R configuration" and its unique benefits. A party might argue that the claims require a level of purity sufficient to manifest these touted advantages, potentially pointing to the "95% (w/w)" language as the minimum standard intended by the inventors for the "most preferred" embodiment.

VI. Other Allegations

• Indirect Infringement: The complaint alleges infringement of method of use claims (Compl. ¶43). The basis for indirect infringement under 35 U.S.C. § 271(e)(2) is Hetero's act of filing an ANDA for a drug to be used in a patented method. The product's proposed label, which would instruct physicians and patients on the infringing use (treating seizures), would be the instrument of inducement (Compl. ¶¶ 15, 29).
• Willful Infringement: The complaint alleges that Hetero was aware of the '551 patent when it filed its ANDA (Compl. ¶31). The willfulness allegation is further supported by the extensive history of the prior litigation, which included a Markman ruling and Hetero's own stipulation of infringement (Compl. ¶¶ 35-36). The subsequent re-filing of a certification of invalidity/non-infringement forms the basis for an allegation of egregious conduct. Plaintiffs seek a determination that the case is "exceptional" under 35 U.S.C. § 285 (Compl. p. 10, ¶G).

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

• A core issue will be one of judicial estoppel: given Defendant’s alleged prior stipulation that its product infringes the asserted claims, to what extent is it precluded from re-litigating infringement, thereby focusing the case almost exclusively on its challenge to the patent's validity?
• A second central question relates to willfulness and exceptionality: does Defendant's decision to re-initiate a patent challenge by filing a new Paragraph IV certification for the same product, after years of litigation and a stipulation of infringement, constitute the type of egregious conduct necessary to support a finding of willful infringement or an "exceptional case" award of attorneys' fees?
• Finally, the case will present a key question of patent validity: can Defendant's invalidity contentions—which the complaint alleges are unchanged from the prior litigation—overcome the '551 patent's statutory presumption of validity, particularly in a context where the infringement of the claims by the accused product appears to be well-established?