DCT

1:19-cv-00318

Merck Sharp & Dohme Corp v. Teva Pharma USA Inc

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:19-cv-00318, D. Del., 02/13/2019
  • Venue Allegations: Venue is alleged to be proper as to Teva USA because it is a Delaware corporation. Venue is alleged to be proper as to Teva Israel because it is a foreign corporation subject to personal jurisdiction in the district.
  • Core Dispute: Plaintiff alleges that Defendants' Abbreviated New Drug Applications (ANDAs) seeking approval to market generic versions of Januvia®, Janumet®, Juvisync®, and Janumet XR® constitute an act of infringement of a patent covering a specific phosphate salt form of sitagliptin.
  • Technical Context: The technology concerns a specific salt formulation of a dipeptidyl peptidase-IV (DPP-IV) inhibitor, a class of oral medications used to treat Type 2 diabetes.
  • Key Procedural History: The litigation was triggered by four Paragraph IV notice letters sent by Teva to Merck, informing Merck of Teva's ANDA filings. In these filings, Teva certified that U.S. Patent No. 7,326,708 is invalid, unenforceable, or will not be infringed by its proposed generic products. The complaint notes that Teva did not contest infringement of claim 1 in its notice letters.

Case Timeline

Date Event
2003-06-24 ’708 Patent Priority Date
2008-02-05 ’708 Patent Issue Date
2010-12-14 Teva's Notice Letter for ANDA No. 202487 (generic Januvia)
2010-12-14 Teva's Notice Letter for ANDA No. 202488 (generic Janumet)
2012-12-03 Teva's Notice Letter for ANDA No. 204524 (generic Juvisync)
2013-03-01 Teva's Notice Letter for ANDA No. 204591 (generic Janumet XR)
2019-02-13 Complaint Filing Date

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

U.S. Patent No. 7,326,708 - "Phosphoric Acid Salt of a Dipeptidyl Peptidase-IV Inhibitor"

Issued February 5, 2008 (Compl. ¶34; ’708 Patent, front page).

The Invention Explained

  • Problem Addressed: The patent background notes that while a class of beta-amino tetrahydotriazolo[4,3-a]pyrazines were known to be potent inhibitors of DP-IV for treating Type 2 diabetes, there was no specific disclosure of the particular dihydrogenphosphate salt form of the compound. (’708 Patent, col. 1:49-62). The development of specific salt forms is a critical step in creating a viable, stable, and manufacturable drug product from a base compound.
  • The Patented Solution: The invention is a novel dihydrogenphosphate salt of the active pharmaceutical ingredient 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine, commonly known as sitagliptin. (’708 Patent, col. 1:63 - col. 2:4). The patent asserts this salt form, particularly a crystalline monohydrate version, possesses advantageous properties for pharmaceutical manufacturing, including improved physical and chemical stability and better physicochemical properties like solubility, which are important for creating consistent and effective dosage forms. (’708 Patent, col. 2:5-18).
  • Technical Importance: For an orally administered drug, achieving a stable, crystalline salt form with predictable solubility is critical for ensuring consistent bioavailability and shelf-life, which are fundamental requirements for regulatory approval and commercial success. (’708 Patent, col. 2:5-18).

Key Claims at a Glance

  • The complaint asserts infringement of one or more claims, including at least independent claim 1. (Compl. ¶45).
  • Independent Claim 1:
    • A dihydrogenphosphate salt of 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine of structural formula I
    • or a hydrate thereof.
  • The complaint does not explicitly reserve the right to assert dependent claims but alleges infringement of "one or more claims." (Compl. ¶45).

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are Teva’s proposed generic drug products containing sitagliptin phosphate, as described in ANDA Nos. 202487, 202488, 204524, and 204591. (Compl. ¶1, ¶10).

Functionality and Market Context

The complaint alleges that Teva’s ANDA Products are generic versions of Merck’s branded products Januvia®, Janumet®, Juvisync®, and Janumet XR®. (Compl. ¶3, ¶5, ¶7, ¶9). The key technical feature alleged in the complaint is that these products contain "sitagliptin phosphate as an active ingredient." (Compl. ¶44, ¶64, ¶84, ¶104). These products are intended for the treatment of Type 2 diabetes. The filing of the ANDAs represents a commercial effort by Teva to enter the market for sitagliptin-based therapies upon expiration or invalidation of relevant patents. (Compl. ¶1).

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

The core of the infringement allegation is statutory infringement under 35 U.S.C. § 271(e)(2)(A), which defines the submission of an ANDA as an act of infringement if the proposed product would infringe a patent. (Compl. ¶47).

'708 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A dihydrogenphosphate salt of 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine of structural formula I... or a hydrate thereof. Teva’s '487, '488, '524, and '591 ANDA Products each contain "sitagliptin phosphate as an active ingredient." ¶44, ¶64, ¶84, ¶104 col. 15:64 - col. 16:16

Identified Points of Contention

  • Validity vs. Infringement: The complaint states that Teva, in its notice letters, "did not contest infringement of claim 1 of the '708 patent." (Compl. ¶46, ¶66, ¶86, ¶106). However, Teva's Paragraph IV certification asserts that the patent is "invalid, unenforceable, and/or will not be infringed." (Compl. ¶43, ¶63, ¶83, ¶103). This suggests the central dispute in the litigation may not be over whether Teva's product meets the claim limitations, but rather whether the claims of the '708 Patent are valid and enforceable in the first place.
  • Technical Questions: While infringement of claim 1 is allegedly not contested, the complaint does not specify the exact form (e.g., crystalline, amorphous, specific hydrate) of sitagliptin phosphate in Teva's proposed products. If Teva's product differs from the specific crystalline monohydrate embodiment described in the patent, it raises the question of whether any such differences could form the basis for a non-infringement argument despite the general concession.

V. Key Claim Terms for Construction

  • The Term: "a hydrate thereof"
  • Context and Importance: This term appears in the independent claim and broadens its scope beyond the anhydrous salt. The patent specification places significant emphasis on a specific "crystalline monohydrate" form. (’708 Patent, col. 2:3-4, col. 13:20-25). Practitioners may focus on this term because the infringement analysis could depend on whether Teva's product is a hydrate and, if so, whether its specific form falls within the proper construction of this term.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The plain language of claim 1 uses the indefinite article "a" ("a hydrate"), which could support a construction that covers any form of the salt associated with water, including non-stoichiometric or amorphous hydrates, not just the specific monohydrate embodiment. (’708 Patent, col. 16:16).
    • Evidence for a Narrower Interpretation: An argument for a narrower construction could be based on the specification's repeated and detailed description of a specific, stable "crystalline monohydrate." (’708 Patent, Abstract; col. 2:2-4; FIG. 1, 4, 5). A defendant might argue that the invention is limited to this disclosed stable form, and that other hydrated forms were not contemplated or enabled.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges active inducement, stating that Teva plans to "actively induce infringement" and that its actions "will be done with knowledge of the '708 patent and specific intent to infringe." (Compl. ¶51, ¶71, ¶91, ¶111). The basis for this is the proposed product labeling, which will allegedly direct infringing uses. (Compl. ¶50, ¶70, ¶90, ¶110). Contributory infringement is also alleged, based on the assertion that Teva's products are not staple articles of commerce and are not suitable for substantial noninfringing use. (Compl. ¶52, ¶72, ¶92, ¶112).
  • Willful Infringement: Willfulness is alleged based on Teva having "acted with full knowledge of the '708 patent" as a result of the notice letters and continuing "to assert its intent to manufacture, offer for sale, sell, distribute, and/or import" its ANDA products. (Compl. ¶53, ¶55, ¶73, ¶75, ¶93, ¶95, ¶113, ¶115). The allegations are based on post-notice knowledge.

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

  • A core issue will be one of patent validity: As the complaint alleges that infringement of the primary claim is not contested by Teva, the case will likely center on Teva's defenses, asserted in its Paragraph IV certification, that the '708 patent is invalid or unenforceable. The litigation will turn on the specific grounds for these defenses, such as potential obviousness over the prior art base compound.
  • A central legal question will be inducement and willfulness: The court will need to assess whether Teva's act of filing an ANDA with a Paragraph IV certification, coupled with its alleged knowledge from the notice letters and intent to market its product with infringing labeling, rises to the level of willful infringement or inducement, particularly in the context of the Hatch-Waxman Act framework.