DCT

1:23-cv-00684

AbbVie Inc v. Sun Pharmaceutical Industries Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:23-cv-00684, D. Del., 06/23/2023
  • Venue Allegations: Venue is asserted on the basis that Defendant is a foreign corporation and is subject to personal jurisdiction in the district through its business activities, including its intent to market and sell the accused generic product in Delaware upon receiving regulatory approval.
  • Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff's ORILISSA® product constitutes an act of infringement of a patent covering compositions of the drug's active ingredient, elagolix sodium.
  • Technical Context: The technology concerns pharmaceutical compositions of elagolix sodium, an amorphous active ingredient used to treat endometriosis, focusing on achieving high purity by controlling specific process-related impurities.
  • Key Procedural History: This action was filed under the Hatch-Waxman Act following Plaintiff’s receipt of a Paragraph IV notice letter from Defendant regarding the patent-in-suit. The complaint notes that the same ANDA is the subject of a prior lawsuit filed in 2022 by Plaintiff involving a different set of patents.

Case Timeline

Date Event
2018-07-23 '239 Patent Priority Date
2019-07-23 FDA Approval of ORILISSA® (NDA 210450)
2022-10-27 "First Suit" Filed Against Sun's ANDA
2023-01-03 '239 Patent Issued
2023-05-10 Sun's Second Notice Letter to AbbVie
2023-06-23 Complaint Filed

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

U.S. Patent No. 11,542,239 - "Elagolix Sodium Compositions and Processes", issued January 3, 2023

The Invention Explained

  • Problem Addressed: The patent's background section explains that since the active pharmaceutical ingredient (API) elagolix sodium is "generally amorphous," its purification can be more complex than for substances with stable crystalline forms ('239 Patent, col. 2:53-57). The patent identifies a need for elagolix sodium with a "very low impurity profile" suitable for commercial-scale manufacturing that is "reproducible, efficient, cost-effective and safe" ('239 Patent, col. 2:46-52).
  • The Patented Solution: The invention is a composition of elagolix sodium (identified as Compound (I)) that is substantially pure, defined by having at least 97% of the desired compound by weight and no more than 3% of certain specified impurities ('239 Patent, Abstract; col. 2:16-20). The specification discloses that this high purity can be achieved through processes involving a novel crystalline salicylate salt of a key intermediate (Compound II), which improves manufacturability and purification compared to prior methods that involved difficult liquid-liquid separations ('239 Patent, col. 14:29-41).
  • Technical Importance: This approach provides a method for producing a highly pure amorphous API, which is a critical step in meeting stringent regulatory standards and enabling consistent, large-scale commercial manufacturing ('239 Patent, col. 2:57-62).

Key Claims at a Glance

  • The complaint asserts infringement of at least one claim; independent claim 1 is representative.
  • Independent Claim 1 requires:
    • A composition comprising: Compound (I), which is elagolix sodium;
    • and one or more impurity selected from a specific group of four chemical structures identified as compounds (iii), (v), (vi), and (vii);
    • wherein Compound (I) comprises at least 97 weight percent of the composition;
    • and wherein the one or more impurity is present in an amount greater than zero and equal to or less than 3 weight percent of the composition.
  • The complaint's general allegation of infringement of "one or more claims" suggests the right to assert other independent or dependent claims is reserved (Compl. ¶2).

III. The Accused Instrumentality

Product Identification

  • The accused instrumentality is Sun's proposed generic elagolix sodium oral tablets (equivalent to 150 mg and 200 mg base), as described in its ANDA No. 215804 (Compl. ¶1).

Functionality and Market Context

  • The proposed product is a generic version of Plaintiff's ORILISSA® tablets, which are indicated for the management of moderate to severe pain associated with endometriosis (Compl. ¶1, ¶5). The complaint alleges that Sun's ANDA represents its product as "pharmaceutically and therapeutically equivalent" to ORILISSA®, meaning it contains the same active ingredient and is intended for the same use (Compl. ¶45). The infringement is statutory, based on the filing of the ANDA, rather than the sale of a commercial product (Compl. ¶2).

IV. Analysis of Infringement Allegations

The complaint does not include a claim chart. The infringement theory is based on Sun's filing of an ANDA for a product that is represented to be a generic equivalent of ORILISSA®. The core allegation is that any product meeting the FDA's standards for equivalence to ORILISSA® will necessarily be a composition that falls within the scope of the asserted claims.

No probative visual evidence provided in complaint.

11,542,239 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A composition comprising: Compound (I),... Sun's Generic Product contains elagolix sodium oral tablets as its active ingredient, which corresponds to the chemical structure of Compound (I) (elagolix sodium). ¶1, ¶33, ¶45 col. 2:1-12
and one or more impurity selected from a group consisting of: [compounds (iii), (v), (vi), and (vii)] The complaint alleges that Sun's Generic Product will infringe, which implies that it will contain at least one of the specifically recited impurities as a necessary consequence of being a bioequivalent version of ORILISSA®. ¶46 col. 92:25-45
wherein Compound (I) comprises at least 97 weight percent of the composition Sun's ANDA represents that its product is therapeutically equivalent to ORILISSA®, which allegedly requires it to meet the purity level specified in the claim. ¶45, ¶46 col. 92:46-48
and wherein the one or more impurity is present in an amount that is greater than zero and equal to or less than 3 weight percent of the composition. Sun's ANDA represents that its product is therapeutically equivalent to ORILISSA®, which allegedly requires its impurity profile to fall within the concentration range specified in the claim. ¶45, ¶46 col. 92:49-53
  • Identified Points of Contention:
    • Technical Question: A primary point of contention will be factual: does the product described in Sun's ANDA contain one or more of the four specific impurities recited in Claim 1? The complaint does not provide evidence on this point, which will be a central focus of discovery.
    • Technical Question: Assuming one of the listed impurities is present, does the purity profile of Sun's proposed product meet the claimed weight-percentage limitations (i.e., ≥97% Compound (I) and ≤3% of the specified impurities)?
    • Scope Question: The claim is limited to a composition containing a specific, closed list of impurities. The case may raise the question of whether Sun's manufacturing process is capable of producing elagolix sodium that avoids generating these particular impurities, thereby designing around the patent's scope.

V. Key Claim Terms for Construction

  • The Term: "composition"
  • Context and Importance: The construction of this term is critical for determining the universe of materials to which the weight-percent limitations apply. Practitioners may focus on this term to clarify whether the claim covers the bulk active pharmaceutical ingredient (API) or the final formulated drug product including excipients.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The term is not explicitly defined in the patent, which could support an argument for its plain and ordinary meaning.
    • Evidence for a Narrower Interpretation: The specification consistently discusses the purity of the "elagolix sodium active substance" and the challenges of its purification ('239 Patent, col. 2:53-62). The listed impurities are byproducts of the chemical synthesis process, not formulation excipients. This intrinsic evidence strongly suggests that "composition" refers to the bulk API substance prior to its formulation into the final tablet.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges active inducement of infringement under 35 U.S.C. § 271(b) (Compl. ¶47). This is based on the allegation that Sun's proposed package insert for its generic product will instruct healthcare professionals and patients to administer the drug, which would constitute an infringing use of the claimed composition (Compl. ¶50).
  • Willful Infringement: The complaint does not contain an explicit count for willful infringement. However, it requests a declaration that the case is "exceptional" under 35 U.S.C. § 285, which is often predicated on a finding of willfulness (Compl., p. 13, ¶G). This allegation appears to be based on Sun's alleged knowledge of the '239 patent, as evidenced by its May 10, 2023 notice letter (Compl. ¶51).

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

  • A central issue will be one of evidentiary proof: can AbbVie demonstrate through chemical analysis that Sun’s proposed generic product, as detailed in its ANDA, will necessarily contain one or more of the specific chemical impurities recited in the asserted claims and fall within the claimed weight-percent limitations? The outcome will likely depend on facts established during discovery regarding Sun's manufacturing process and final product specifications.
  • The case will also turn on a question of infringement scope and design-around: does Sun’s manufacturing process for elagolix sodium yield a final API that successfully avoids the specific impurities claimed in the '239 patent? Because the patent claims a composition, not a process, a generic product with a different impurity profile would not infringe, regardless of its therapeutic equivalence to ORILISSA®.