DCT

1:25-cv-00344

Sumitomo Pharma Switzerland GmbH v. Hetero Labs Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

Case Timeline

Date Event
2012-09-28 U.S. Patent No. 11,795,178 Priority Date
2016-09-30 U.S. Patent No. 12,097,198 Priority Date
2016-09-30 U.S. Patent No. 12,144,809 Priority Date
2020-12-18 Orgovyx® (relugolix) New Drug Application (NDA) approved by FDA
2023-10-24 U.S. Patent No. 11,795,178 Issued
2024-09-24 U.S. Patent No. 12,097,198 Issued
2024-11-19 U.S. Patent No. 12,144,809 Issued
2025-02-04 Hetero sends Paragraph IV Notice Letter regarding its relugolix ANDA
2025-03-19 Complaint Filed

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

U.S. Patent No. 11,795,178 - Compositions of Thienopyrimidine Derivatives (issued October 24, 2023)

The Invention Explained

  • Problem Addressed: The patent describes a demand for developing a safe and high-yield production method for a thienopyrimidine derivative (relugolix) that results in a product of high quality and purity (’178 Patent, col. 2:9-15). The control of impurities is a critical aspect of pharmaceutical manufacturing.
  • The Patented Solution: The patent claims a specific composition, or mixture, of the relugolix active ingredient. The invention is not the compound itself, but rather a mixture that includes the active ingredient along with a specific, named impurity—6-(4-aminophenyl)-1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione—at a controlled level of 4.45% or less, as measured by high-performance liquid chromatography (HPLC) (’178 Patent, col. 31:65-32:9). This suggests the invention resides in achieving a defined purity profile for the final drug product.
  • Technical Importance: For an orally administered drug, controlling the impurity profile is crucial for ensuring safety, efficacy, and batch-to-batch consistency, which are fundamental requirements for regulatory approval and safe patient use (’178 Patent, col. 2:9-15).

Key Claims at a Glance

  • The complaint asserts independent claims 1 and 25, along with dependent claims 26-28 (Compl. ¶48).
  • Independent Claim 1 requires:
    • A mixture comprising 1-{4-[1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-6-yl]phenyl}-3-methoxyurea (relugolix).
    • The mixture also comprises a second compound, 6-(4-aminophenyl)-1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione.
    • This second compound is present in an amount of about 4.45% or less of the mixture, as determined by HPLC.
  • The complaint does not specify which dependent claims may be asserted beyond those listed (Compl. ¶48).

U.S. Patent No. 12,097,198 - Treatment of Prostate Cancer (issued September 24, 2024)

The Invention Explained

  • Problem Addressed: The patent background describes challenges with existing prostate cancer treatments, particularly GnRH agonists, which are administered via injection and can cause an initial "clinical flare"—a temporary worsening of symptoms due to a surge in testosterone. This creates a need for an oral treatment that avoids this flare and allows for more flexible dosing, including easier suspension and resumption of therapy (’198 Patent, col. 2:4-23).
  • The Patented Solution: The invention is a method for treating prostate cancer by administering a specific oral formulation of relugolix once-daily at a dose of at least 80 mg (’198 Patent, col. 61:24-34). This method is designed to rapidly suppress testosterone to castration levels without the initial testosterone surge seen with agonists, offering a more convenient and potentially safer oral treatment regimen (’198 Patent, col. 2:13-23). The patent includes extensive clinical data in its figures and description, demonstrating the effect of various doses on hormone levels over time (’198 Patent, FIG. 1, FIG. 7).
  • Technical Importance: An effective oral GnRH antagonist provides a significant clinical alternative to injected depot formulations, offering greater patient convenience and allowing physicians more control over the treatment course, including the ability to pause therapy if needed for other medical reasons.

Key Claims at a Glance

  • The complaint asserts independent claim 1, among others (Compl. ¶58).
  • Independent Claim 1 requires a method for treating prostate cancer in a subject, comprising:
    • Administering once-daily to the subject.
    • An oral formulation comprising at least 80 mg of N-(4-(1-(2,6-difluorobenzyl)-5-((dimethylamino)methyl)-3-(6-methoxy-3-pyridazinyl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-6-yl)phenyl)-N'-methoxyurea (relugolix), or a corresponding amount of a pharmaceutically acceptable salt thereof.
  • The complaint also asserts claims 2, 4-6, and 10-12 (Compl. ¶58).

U.S. Patent No. 12,144,809 - Treatment of Prostate Cancer (issued November 19, 2024)

The Invention Explained

  • Technology Synopsis: This patent, like the ’198 Patent, is directed to methods of treating prostate cancer with relugolix. It specifically claims dosing regimens that involve an initial oral loading dose (e.g., 360 mg) followed by a daily oral maintenance dose (e.g., 120 mg) to achieve and maintain testosterone suppression (’809 Patent, col. 143:43-144:67). This approach is designed to rapidly achieve therapeutic hormone levels.

Key Claims at a Glance

  • Asserted Claims: Claims 1, 3, 5, 9, 12, 19, and 23-29 are asserted (Compl. ¶68). Independent claim 1 is among the asserted claims.
  • Accused Features: Hetero’s ANDA Product, a 120 mg relugolix tablet, is accused of infringing because its proposed use for treating prostate cancer will follow the patented dosing methods (Compl. ¶¶ 68-71).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Hetero’s proposed generic version of Orgovyx®, described as 120 mg tablets of relugolix, submitted for FDA approval under ANDA No. 220143 (the "ANDA Product") (Compl. ¶1, ¶40).

Functionality and Market Context

The complaint alleges that Hetero's ANDA Product has the same active ingredient (relugolix), dosage form (tablet), and strength (120 mg) as the branded drug Orgovyx® and is bioequivalent to it (Compl. ¶41). Relugolix functions as a nonpeptide GnRH receptor antagonist for oral administration, approved for treating adult patients with advanced prostate cancer (Compl. ¶33). The filing of the ANDA signifies Hetero’s intent to market this generic product in the United States upon receiving FDA approval (Compl. ¶42).

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

U.S. Patent No. 11,795,178 Infringement Allegations

Claim Element (from Independent Claim 1) - Alleged Infringing Functionality - Complaint Citation Patent Citation
a mixture comprising 1-{4-[1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-6-yl]phenyl}-3-methoxyurea... The complaint alleges that Hetero's ANDA Product will be a generic version of Orgovyx® and will therefore contain the claimed relugolix compound as its active ingredient. - ¶1, ¶41 col. 31:66-32:2
and 6-(4-aminophenyl)-1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione - The complaint does not provide specific detail on the impurity profile of Hetero's ANDA Product but alleges that the product will infringe, which implies the presence of the claimed mixture. - ¶49, ¶50 col. 32:3-9
wherein the 6-(4-aminophenyl)-1-(2,6-difluorobenzyl)-5-dimethylaminomethyl-3-(6-methoxypyridazin-3-yl)thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione is present in an amount of about 4.45% or less of the mixture... The complaint alleges that the commercial manufacture and sale of the ANDA product will infringe the claims, suggesting the impurity will be present within the claimed percentage range. - ¶49, ¶50 col. 32:10-16

U.S. Patent No. 12,097,198 Infringement Allegations

Claim Element (from Independent Claim 1) - Alleged Infringing Functionality - Complaint Citation Patent Citation
A method for treating prostate cancer in a subject... - The complaint alleges that Hetero's ANDA product, a generic version of Orgovyx®, is intended for the treatment of prostate cancer. - ¶1, ¶33, ¶40 col. 1:11-14
...comprising administering once-daily to the subject, an oral formulation... - The proposed labeling for Hetero's ANDA product will allegedly instruct or encourage healthcare providers and patients to administer the drug on a once-daily, oral basis. - ¶61 col. 61:25-27
...comprising at least 80 mg of N-(4-(1-(2,6-difluorobenzyl)-5-((dimethylamino)methyl)-3-(6-methoxy-3-pyridazinyl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-6-yl)phenyl)-N'-methoxyurea... Hetero's ANDA Product is a 120 mg tablet of relugolix, which satisfies the "at least 80 mg" dosage limitation. - ¶1, ¶40 col. 61:27-33

Identified Points of Contention

  • Scope Questions: For the ’178 Patent, a central issue may be whether Hetero’s ANDA product will, in fact, constitute the claimed "mixture." This raises the evidentiary question of whether Hetero's manufacturing process results in the specified impurity at the claimed level. For the ’198 and ’809 Patents, a key question for induced infringement will be the precise language of Hetero’s proposed product labeling and whether it directs users to perform all steps of the claimed methods.
  • Technical Questions: A potential technical dispute regarding the ’178 Patent could concern the specific HPLC method used to measure the impurity percentage. The claim recites measurement "as determined by high performance liquid chromatography (HPLC)," and parties may dispute whether Hetero's quality control methods are consistent with the method implicitly or explicitly defined by the patent.

V. Key Claim Terms for Construction

  • The Term: "a mixture comprising" (from ’178 Patent, Claim 1)

    • Context and Importance: This term is fundamental to the composition claim of the ’178 Patent. The dispute may turn on whether the presence of the active ingredient and the specified impurity, along with other excipients in a final tablet form, constitutes the claimed "mixture," or if the term implies a more specific relationship between the two listed chemical compounds established during manufacturing. Practitioners may focus on this term because its construction determines whether the claim covers the final drug product or only an intermediate composition.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The use of the open-ended term "comprising" suggests the mixture can include other unlisted ingredients, such as pharmaceutical excipients, which may support an interpretation that the claim reads on a final drug product. The patent's claims extend to pharmaceutical compositions containing the mixture, which could imply the "mixture" itself is a component within the larger composition (’178 Patent, col. 32:29-31).
      • Evidence for a Narrower Interpretation: The specification focuses heavily on production methods and the purity of the active pharmaceutical ingredient (’178 Patent, col. 2:9-15). This context could support an argument that the claimed "mixture" refers specifically to the active ingredient bulk substance before it is formulated with excipients into a final tablet.

  • The Term: "administering once-daily" (from ’198 Patent, Claim 1)

    • Context and Importance: The definition of this term is critical for determining infringement of the method claims in the ’198 and ’809 Patents. The infringement analysis will question whether the instructions on Hetero’s proposed label will direct a course of treatment that meets this limitation. Practitioners may focus on this term because deviations from a strict once-every-24-hours schedule (e.g., missed doses, patient non-compliance) could be argued to fall outside the claim scope, impacting the analysis of induced infringement.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The patent describes clinical studies where patients were administered the drug on a once-daily basis as a general regimen, which is the common understanding in the pharmaceutical field and implies a standard daily dosing schedule rather than a rigid, minute-by-minute requirement (’198 Patent, col. 61:35-43).
      • Evidence for a Narrower Interpretation: The patent’s detailed description and figures show pharmacokinetic and pharmacodynamic data tied to specific, controlled dosing intervals from clinical trials (’198 Patent, FIG. 1, FIG. 7). A defendant may argue that the term should be limited to the controlled conditions under which the patented effects were demonstrated, potentially excluding real-world scenarios with less-than-perfect patient adherence.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents-in-suit. The inducement allegations are based on the assertion that Hetero's marketing and proposed product labeling for its ANDA Product will intentionally encourage and instruct healthcare providers and patients to use the generic drug in a manner that directly infringes the patented methods of use (’198 Patent, Compl. ¶61; ’809 Patent, Compl. ¶71). The contributory infringement allegations are based on the assertion that Hetero’s ANDA product is not a staple article of commerce and is especially made or adapted for use in an infringing manner (’178 Patent, Compl. ¶52; ’198 Patent, Compl. ¶62; ’809 Patent, Compl. ¶72).
  • Willful Infringement: The complaint does not use the word "willful" but alleges that this is an "exceptional case" under 35 U.S.C. § 285 for each asserted patent (Compl. ¶¶ 55, 65, 75). This allegation is based on Hetero's alleged knowledge of the patents-in-suit, at least as of the date it submitted its ANDA, and its proceeding to seek FDA approval "without a reasonable basis for believing that it would not be liable" (Compl. ¶¶ 55, 65, 75).

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

  • A core issue will be one of evidentiary proof: for the ’178 Patent, can Plaintiffs demonstrate that Hetero's future commercial product will necessarily contain the specific impurity at the levels defined by the "mixture" claim? This will likely require analysis of Hetero's confidential ANDA filing and potentially testing of product samples.
  • A central question will be one of induced infringement: for the ’198 and ’809 method-of-use patents, does the language of Hetero's proposed drug label actively instruct or merely describe a condition of use? The outcome may depend on whether the label is found to teach physicians and patients to perform the patented dosing regimens, thereby inducing infringement.
  • A foundational dispute will be over validity: Hetero has asserted in its Paragraph IV letter that the patents are invalid. A key question for the court will be whether Hetero can present clear and convincing evidence to invalidate the asserted claims, potentially based on prior art that was not before the patent office or arguments that the claimed inventions would have been obvious to a person of ordinary skill in the art.