DCT

1:20-cv-01585

Boehringer Ingelheim Pharma Inc v. Sun Pharmaceutical Industries Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:20-cv-01585, D. Del., 11/23/2020
  • Venue Allegations: Venue is alleged to be proper in the District of Delaware because certain defendants are incorporated in the state, and thus "reside" there for venue purposes, and/or have committed acts of infringement and maintain a regular and established place of business in the district.
  • Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (“ANDA”) to the FDA seeking approval to market a generic version of Plaintiff's TRIJARDY XR® tablets constitutes an act of patent infringement.
  • Technical Context: The patent-in-suit relates to a class of chemical compounds known as glucopyranosyl-substituted phenyl derivatives, which function as SGLT2 inhibitors for the treatment of metabolic disorders such as type 2 diabetes.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following Plaintiff's receipt of a Paragraph IV Certification letter from Defendant on or about October 14, 2020. In that letter, Defendant asserted that certain claims of the patent-in-suit are either invalid or will not be infringed by the commercial manufacture or sale of its proposed generic product.

Case Timeline

Date Event
2004-03-16 U.S. Patent No. 7,579,449 Priority Date
2009-08-25 U.S. Patent No. 7,579,449 Issue Date
2020-10-14 Plaintiff receives Defendant’s Paragraph IV Certification letter
2020-11-23 Complaint Filing Date

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

U.S. Patent No. 7,579,449 - "Glucopyranosyl-Substituted Phenyl Derivatives, Medicaments Containing Such Compounds, Their Use and Process For Their Manufacture", issued August 25, 2009

The Invention Explained

  • Problem Addressed: The patent seeks to identify new chemical compounds that exhibit an enhanced inhibitory effect on the sodium-dependent glucose cotransporter SGLT2, as well as improved pharmacological or pharmacokinetic properties, compared to structurally similar compounds known in the prior art (’449 Patent, col. 2:56-65).
  • The Patented Solution: The invention discloses a class of glucopyranosyl-substituted benzene derivatives, defined by a general chemical structure (Formula I), that are described as having an inhibitory effect on SGLT2 ('449 Patent, Abstract; col. 2:44-48). By inhibiting this transporter, which is involved in glucose reabsorption in the kidneys, the compounds are intended for use in treating metabolic disorders, particularly diabetes ('449 Patent, col. 2:2-5).
  • Technical Importance: The development of selective SGLT2 inhibitors provided a novel therapeutic mechanism for managing hyperglycemia in patients with type 2 diabetes by promoting the excretion of glucose in the urine ('449 Patent, col. 29:3-10).

Key Claims at a Glance

  • The complaint alleges infringement of "at least one claim" of the patent without specifying which claims are asserted (Compl. ¶37). Independent claim 1 is a composition of matter claim defining a broad class of compounds.
  • The essential elements of independent claim 1 define a glucopyranosyl-substituted benzene derivative according to a specific chemical structure (Formula 1.2c) with the following key variable substituents:
    • R¹ is selected from a group including hydrogen, fluorine, chlorine, bromine, cyano, methyl, ethyl, and others.
    • R² is selected from a group including hydrogen, fluorine, hydroxy, methoxy, and others.
    • R³ is selected from a group including trimethylsilylethyl, ethynyl, various substituted ethynyl and propynyl groups, and various cyclic ether groups such as cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, and tetrahydrofuran-3-yloxy.
    • R⁴ and R⁵ are independently defined as hydrogen or fluorine.
    • R⁶, R⁷ᵃ, R⁷ᵇ, and R⁷ᶜ are defined as hydrogen or specific acyl groups, with the claim reciting that R⁷ᵃ, R⁷ᵇ, and R⁷ᶜ are hydrogen.
  • The complaint’s broad allegation of infringing "at least one claim" may be interpreted to implicitly include dependent claims (Compl. ¶37, ¶39).

III. The Accused Instrumentality

Product Identification

Defendant Sun’s proposed generic empagliflozin/linagliptin/metformin hydrochloride extended-release tablets (the "Sun ANDA Product"), for which it submitted ANDA No. 214843 to the FDA (Compl. ¶11).

Functionality and Market Context

The Sun ANDA Product is a generic drug intended to be a therapeutic equivalent to Plaintiff’s branded TRIJARDY XR® tablets, which are used to treat type 2 diabetes (Compl. ¶1, ¶35). The complaint alleges that the '449 Patent is listed in the FDA's "Orange Book" as covering the pharmaceutical composition and use of TRIJARDY XR®, which contains empagliflozin, one of the active ingredients in the Sun ANDA Product (Compl. ¶31, ¶32). The act of infringement alleged is the submission of the ANDA seeking approval to market this generic product in the United States prior to the expiration of the ’449 Patent (Compl. ¶1, ¶37).

IV. Analysis of Infringement Allegations

The complaint does not provide a claim chart or detailed, element-by-element infringement allegations. The central allegation is that Defendant committed a statutory act of infringement under 35 U.S.C. § 271(e)(2)(A) by submitting its ANDA for a product containing a compound allegedly covered by the '449 Patent (Compl. ¶37). The theory is that the empagliflozin active pharmaceutical ingredient in the Sun ANDA Product is a chemical compound that falls within the scope of at least one claim of the patent, and the future commercial manufacture, use, or sale of the product would constitute direct infringement (Compl. ¶32, ¶39).

No probative visual evidence provided in complaint.

Identified Points of Contention

  • Scope Questions: A primary issue will be whether the specific chemical structure of empagliflozin, the active ingredient in the accused product, is encompassed by the scope of an asserted claim of the ’449 Patent. The analysis will turn on whether empagliflozin's structure meets all limitations of the Markush groups defined in the asserted claim(s).
  • Technical Questions: The complaint relies on the Orange Book listing for TRIJARDY XR® to assert that the ’449 Patent covers empagliflozin (Compl. ¶31, ¶32). A key question for the court will be the factual and legal sufficiency of this basis for infringement, particularly in light of Defendant’s assertion of non-infringement in its Paragraph IV Certification letter (Compl. ¶36).

V. Key Claim Terms for Construction

The complaint does not provide sufficient detail for a full analysis of claim construction disputes. However, based on the known structure of empagliflozin, certain terms may become central to the case.

  • The Term: "tetrahydrofuran-3-yloxy"
  • Context and Importance: The empagliflozin molecule contains a tetrahydrofuran-3-yloxy substituent at a position corresponding to the R³ variable in the claimed chemical structure. The interpretation of this term within the context of the larger Markush group defining R³ in claim 1 will be fundamental to the infringement analysis.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent explicitly recites "tetrahydrofuran-3-yloxy" as one of the possible species for the R³ group in independent claim 1 ('449 Patent, col. 67:25-34). The specification further provides working examples for synthesizing compounds containing both the (R)- and (S)-stereoisomers of this group, suggesting the term as used in the claim is not limited to a particular stereoisomer ('449 Patent, col. 17:19-25, Examples 1(2) and 1(3)).
    • Evidence for a Narrower Interpretation: A party seeking a narrower construction might argue that statements made during prosecution or subtle distinctions in the specification limit the scope of the term. For example, arguments could arise concerning the stereochemistry of the tetrahydrofuran ring, even though it is not specified in the claim language itself.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendant's future sale of the Sun ANDA Product would induce infringement by others, such as patients and physicians, based on Defendant's knowledge of the ’449 Patent and its promotional activities and package inserts that will allegedly instruct on an infringing use (Compl. ¶43, ¶44). It also alleges contributory infringement, stating the product is a material component of the invention, is not a staple article of commerce, and is especially adapted for an infringing use (Compl. ¶41).
  • Willful Infringement: The complaint does not contain an explicit allegation of willful infringement. However, it does request a finding that the case is "exceptional" under 35 U.S.C. § 285, which would entitle Plaintiff to an award of attorney's fees (Compl. ¶47). This allegation is based on the totality of the circumstances, including Defendant’s alleged knowledge of the patent as evidenced by its Paragraph IV certification (Compl. ¶36, ¶43).

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

  • A core issue will be one of claim scope: does the specific chemical compound empagliflozin, including its stereochemistry, fall within the literal scope of at least one asserted claim of the '449 Patent? The resolution will depend on the judicial construction of the terms defining the variable R³ substituent in the patent's Markush claims.
  • A second central question will be patent validity: in response to the infringement claim, the case will almost certainly involve a challenge to the validity of the asserted patent claims. As indicated by Defendant's Paragraph IV letter, the court will likely be asked to determine whether the asserted claims are valid over the prior art, an issue that lies at the heart of nearly all Hatch-Waxman litigation.