DCT

1:23-cv-00881

AbbVie Inc v. Alkem Laboratories Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:23-cv-00881, D. Del., 08/10/2023
  • Venue Allegations: Plaintiff alleges venue is proper because Defendant is a foreign corporation subject to personal jurisdiction in the district. Personal jurisdiction is asserted based on Defendant's alleged continuous and systematic contacts with Delaware, its intent to sell the accused product in the state, and its history of litigating in the district without challenging jurisdiction.
  • Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Plaintiff’s ORILISSA® drug constitutes an act of infringement of a patent covering specific compositions of elagolix sodium.
  • Technical Context: The technology concerns pharmaceutical compositions of elagolix sodium, a GnRH receptor antagonist used for managing pain associated with endometriosis, a condition affecting a significant number of women.
  • Key Procedural History: This action was filed under the Hatch-Waxman Act following AbbVie’s receipt of a Paragraph IV Notice Letter from Alkem, which certified that Alkem’s generic product would not infringe the patent-in-suit or that the patent is invalid. AbbVie filed this suit within the 45-day statutory window, triggering a 30-month stay on the FDA’s approval of Alkem’s ANDA. This case is related to a prior lawsuit between the parties over the same ANDA, but concerning a different set of patents.

Case Timeline

Date Event
2018-07-23 ’239 Patent Priority Date
2018-07-23 ORILISSA® (NDA No. 210450) FDA Approval
2022-09-23 Alkem's First Notice Letter (related to "First Suit")
2022-10-27 "First Suit" Filed (Case No. 22-1423)
2023-01-03 ’239 Patent Issue Date
2023-06-26 Alkem's Second Notice Letter (for '239 patent)
2023-08-10 Complaint Filing Date

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

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

  • Patent Identification: 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 notes that the active pharmaceutical ingredient elagolix sodium is "generally amorphous," which can make its purification more complex compared to substances with established crystalline forms (’239 Patent, col. 2:52-56). The patent identifies a need for elagolix sodium with a very low, controlled impurity profile that meets regulatory standards and is suitable for efficient, cost-effective, and safe commercial-scale manufacturing (’239 Patent, col. 2:46-62).
  • The Patented Solution: The invention claims to solve this problem by defining a composition of elagolix sodium (identified as Compound (I)) that is substantially pure. Specifically, the patent claims compositions comprising at least 97% or 98% by weight of elagolix sodium and, critically, not more than a specified small percentage (e.g., 3%) of one or more impurities from a defined list of chemical structures (’239 Patent, Abstract; col. 2:16-23). This provides a defined, highly pure product with a known and limited impurity profile.
  • Technical Importance: For a commercially marketed pharmaceutical, achieving a high degree of purity and maintaining a consistent, minimal impurity profile is essential for obtaining and maintaining regulatory approval and ensuring patient safety (’239 Patent, col. 2:57-62).

Key Claims at a Glance

  • The complaint asserts infringement of at least one claim, without specifying which. The primary independent claims are composition claims 1, 5, 9, and 11, each defining a composition with different sets of specified impurities.
  • The essential elements of representative independent Claim 1 are:
    • A composition comprising: Compound (I) (elagolix sodium).
    • And one or more impurities selected from a specific group of five chemical structures identified as (iii), (v), (vi), (vii), and (viii).
    • 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.

III. The Accused Instrumentality

Product Identification

  • The accused instrumentality is "Alkem's Generic Product," a proposed generic version of ORILISSA® (elagolix sodium) oral tablets in 150 mg and 200 mg dosage forms, for which Alkem has filed ANDA No. 217668 seeking FDA approval (Compl. ¶¶1, 37).

Functionality and Market Context

  • The accused generic product is intended to be a substitute for ORILISSA® and is alleged to be "pharmaceutically and therapeutically equivalent" to it (Compl. ¶45). Its function is to act as a GnRH receptor antagonist for the management of endometriosis-associated pain (Compl. ¶5). The complaint alleges that upon approval, Alkem will market and sell the product in the United States, in direct competition with AbbVie’s branded product (Compl. ¶¶16, 41).

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 the ANDA is the statutory act of infringement. The substantive infringement analysis rests on the allegation that the product specified in Alkem's ANDA, if commercially produced, would meet all limitations of the asserted patent claims. The complaint does not include a claim chart. The following table summarizes the infringement theory for representative Claim 1 based on the complaint's allegations.

'239 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A composition comprising: Compound (I), [elagolix sodium] Alkem's Generic Product is a composition containing elagolix sodium, which is Compound (I) of the patent. ¶37, ¶45 col. 91:2-19
and one or more impurity selected from a group consisting of: [structures (iii), (v), (vi), (vii), and (viii)] The complaint alleges that Alkem's Generic Product, as specified in its ANDA, will contain a composition that infringes, which implies it will contain one or more of the claimed impurities. ¶38, ¶47 col. 91:23-col. 92:44
wherein Compound (I) comprises at least 97 weight percent of the composition The complaint's allegation that the ANDA product is therapeutically equivalent to ORILISSA® implies it meets the high purity standards that are alleged to be covered by this claim limitation. ¶45 col. 92:45-46
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. The composition defined in Alkem's ANDA is alleged to meet this quantitative limitation regarding the maximum allowable level of the specified impurity. ¶45 col. 92:47-49
  • Identified Points of Contention:
    • Factual Question: The central dispute will likely be factual: does the composition of the generic drug, as detailed in Alkem's confidential ANDA submission, actually contain one or more of the specific impurities listed in the asserted claims (e.g., in Claim 1), and do the relative amounts of elagolix sodium and any such impurities fall within the claimed percentage ranges?
    • Scope Question: A key legal question, potentially tied to Alkem's invalidity defense (Compl. ¶38), is whether claiming a specific purity level of a known compound constitutes a patentable invention over the prior art processes for making that compound.

V. Key Claim Terms for Construction

  • The Term: "a composition comprising"

  • Context and Importance: This phrase appears at the start of every independent claim. Its construction is critical to determining if the presence of a claimed impurity is a required element for infringement. If Alkem were to produce elagolix sodium with an impurity not on the claimed list, or with no impurities at all, the question of whether its product is still "a composition comprising" the claimed elements would be central. Practitioners may focus on this term to determine if the claims can be designed around.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The term "comprising" is well-established as open-ended, meaning the composition can include other, unlisted components. A party could argue the claims are not limited to only Compound (I) and the listed impurities.
    • Evidence for a Narrower Interpretation: The structure "comprising Compound (I) ... and one or more impurity" suggests that the presence of both the active ingredient and at least one listed impurity is required. The patent’s detailed description emphasizes the invention as a product with a controlled, known impurity profile, not just the pure compound itself (’239 Patent, col. 2:46-62).

  • The Term: "at least about 97 weight percent"

  • Context and Importance: The word "about" introduces a degree of ambiguity to the numerical purity threshold. The scope of "about" will define the lower boundary for infringement. A product with 96.8% purity might be infringing or non-infringing depending on the construction of this term.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The specification uses "about" repeatedly in the context of weight percentages and other measurements, suggesting the patentee did not intend for the claim to be limited to the exact numerical value but to encompass minor, reasonable variations (’239 Patent, col. 2:18, 2:21, 2:60).
    • Evidence for a Narrower Interpretation: The patent’s focus is on achieving high purity to meet stringent standards. A party could argue that "about" should be construed narrowly to mean only the degree of variability inherent in standard measurement techniques. The patent also provides numerous examples with precise measurements, which could suggest that the inventors were capable of, and intended, greater precision (’239 Patent, col. 81-90, Examples 12-29).

VI. Other Allegations

  • Indirect Infringement: The complaint alleges active inducement under 35 U.S.C. § 271(b). The factual basis is Alkem’s alleged knowledge of the ’239 Patent, as evidenced by its Paragraph IV notice letter, and its intent for healthcare providers to prescribe and patients to use the generic product in accordance with its proposed package insert, which allegedly describes an infringing use (Compl. ¶¶49-51).
  • Willful Infringement: The complaint does not use the term "willful," but it requests a finding that the case is "exceptional" and an award of attorney fees, which is the relief typically associated with findings of willful infringement or litigation misconduct in ANDA cases (Compl. ¶G, Request for Relief). The basis for this allegation is Alkem's knowledge of the patent, at the latest, upon sending its notice letter dated June 26, 2023 (Compl. ¶51).

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

  • A key evidentiary question will be one of compositional fact: does the product defined in Alkem’s confidential ANDA literally fall within the scope of AbbVie’s claims? This will require discovery of Alkem’s manufacturing specifications to determine if its generic product contains the specific impurities within the specific quantitative ranges claimed in the ’239 patent.
  • A core issue will be one of patentability and scope: are the claims, which are directed to specific purity profiles of a known compound, valid in light of the prior art? The court will likely have to assess whether achieving these particular purity levels would have been obvious to a person of ordinary skill in the art at the time of the invention.
  • A determinative legal question may be one of definitional breadth: what is the proper construction of the term "about" as it applies to the weight-percent limitations in the claims? The court's interpretation will establish the precise boundary between infringement and non-infringement for Alkem's product.