DCT

1:16-cv-02442

AstraZeneca Ab v. Hetero USA Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:16-cv-02442, D.N.J., 04/29/2016
  • Venue Allegations: Plaintiffs allege venue is proper in the District of New Jersey because Defendant Hetero USA Inc. maintains its principal place of business there and acts as an agent for the other Hetero entities. The complaint further alleges that Defendants transact business in the state and have purposefully availed themselves of New Jersey law.
  • Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) to market a generic version of the heartburn medication NEXIUM® 24HR constitutes an act of infringement of two patents covering a specific crystalline form of esomeprazole magnesium.
  • Technical Context: The technology concerns a specific stable, crystalline hydrate form of esomeprazole, a popular proton pump inhibitor that reduces stomach acid.
  • Key Procedural History: This is a Hatch-Waxman action filed under 35 U.S.C. § 271(e)(2), triggered by Hetero’s submission of ANDA No. 208939 and a corresponding Paragraph IV certification notice. The complaint also notes numerous other, similar patent litigations initiated by the same plaintiffs against other generic drug manufacturers concerning the same patents-in-suit.

Case Timeline

Date Event
1997-05-30 Earliest Priority Date for '085 & '070 Patents
2002-04-09 '085 Patent Issue Date
2008-08-12 '070 Patent Issue Date
2016-03-17 Date of Defendant's ANDA Notice Letter
2016-04-29 Complaint Filing Date

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

U.S. Patent No. 6,369,085 - "Form of S-omeprazole," Issued April 9, 2002

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of developing a stable and consistent form of S-omeprazole, the therapeutically active single enantiomer of the widely used drug omeprazole. The background notes that single enantiomers can offer improved therapeutic profiles but also recognizes that S-omeprazole can exist in multiple, structurally different forms, which can complicate manufacturing and product stability ('085 Patent, col. 1:31-51, col. 2:11-13).
  • The Patented Solution: The invention is a "novel form" of the magnesium salt of S-omeprazole, specifically a trihydrate ('085 Patent, Abstract; col. 1:10-12). This trihydrate form is described as a "well defined compound" that is "more stable" and "easier to handle and store" than prior art forms of the compound. Its stability and high crystallinity are intended to make it easier to synthesize reproducibly on a large scale ('085 Patent, col. 2:15-29). The patent specifically characterizes this novel form by its unique X-ray powder diffractogram (XRPD) pattern ('085 Patent, Fig. 1; col. 2:40-49).
  • Technical Importance: The invention provided a specific, stable, and highly crystalline solid form of S-omeprazole, which is a critical feature for enabling large-scale, consistent pharmaceutical manufacturing and formulation ('085 Patent, col. 2:21-29).

Key Claims at a Glance

  • The complaint asserts infringement of one or more claims without specifying them (Compl. ¶33). Independent Claim 1 is representative:
  • Independent Claim 1:
    • The magnesium salt of S-omeprazole trihydrate,
    • wherein the compound is characterized by a specific set of major peaks in its X-ray diffractogram.

U.S. Patent No. 7,411,070 - "Form of S-omeprazole," Issued August 12, 2008

The Invention Explained

  • Problem Addressed: As a continuation of the '085 Patent, the '070 Patent addresses the same technical problem: the need for a stable, pure, and reliably manufacturable form of S-omeprazole for use in pharmaceutical products ('070 Patent, col. 2:26-34).
  • The Patented Solution: The solution described in the specification is the same as in the '085 Patent: a novel, highly crystalline trihydrate form of the magnesium salt of S-omeprazole. This form is asserted to be more stable and easier to handle in production than other known forms, and is identified by characteristics such as its XRPD pattern ('070 Patent, col. 2:20-34, Fig. 1).
  • Technical Importance: The development of this stable crystalline form was important for the creation of a commercial drug product (NEXIUM®) with a more consistent therapeutic profile than the racemic version of the drug ('070 Patent, col. 2:50-54).

Key Claims at a Glance

  • The complaint asserts infringement of one or more claims (Compl. ¶40). Independent Claim 1 is representative:
  • Independent Claim 1:
    • The magnesium salt of S-omeprazole trihydrate.

III. The Accused Instrumentality

Product Identification

"Hetero's Esomeprazole Magnesium Delayed-Release Capsules, 20 mg Eq. Base," for which Defendant filed Abbreviated New Drug Application (ANDA) No. 208939 with the FDA (Compl. ¶16).

Functionality and Market Context

The accused instrumentality is the filing of the ANDA itself, which seeks FDA approval for a generic version of Plaintiffs' NEXIUM® 24HR product (Compl. ¶¶1, 16). The product is an oral capsule intended to treat frequent heartburn by inhibiting gastric acid secretion (Compl. ¶¶11, 34). As an ANDA product, it is intended to be bioequivalent to the branded drug and, according to the complaint, contains the same active pharmaceutical ingredient, esomeprazole magnesium trihydrate (Compl. ¶¶11, 16).

IV. Analysis of Infringement Allegations

The complaint provides a "notice pleading" of infringement typical in ANDA litigation and does not contain an element-by-element claim chart. The infringement analysis is based on the statutory act of filing an ANDA with a Paragraph IV certification for a product that, if marketed, would infringe the asserted patents.

No probative visual evidence provided in complaint.

'085 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
The magnesium salt of S-omeprazole trihydrate, Defendant's ANDA seeks approval for a generic version of NEXIUM® 24HR, the active ingredient of which is esomeprazole magnesium trihydrate. An ANDA filing implies the generic product contains the same active ingredient as the branded drug. ¶¶11, 16, 33 col. 10:17-18
wherein the compound is characterized by the following major peaks in its X-ray diffractogram... By seeking to market a generic version of a product covered by the '085 patent, Defendant's ANDA product is alleged to possess the same specific crystalline structure defined by the XRPD peaks recited in the claim. The filing of the ANDA is the alleged act of infringement under 35 U.S.C. § 271(e)(2). ¶¶32, 33 col. 10:19-29

'070 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
The magnesium salt of S-omeprazole trihydrate Defendant's ANDA filing for a generic version of NEXIUM® 24HR, whose active ingredient is esomeprazole magnesium trihydrate, is alleged to constitute infringement of this claim, as the proposed generic product is necessarily or contains this chemical compound. ¶¶11, 16, 40 col. 10:52
  • Identified Points of Contention:
    • Technical Question: A central factual dispute will likely be whether the esomeprazole magnesium in Defendant's ANDA product is the specific crystalline trihydrate form claimed in the '085 Patent. Defendant's non-infringement defense, noted in its Paragraph IV certification letter, suggests it may argue that its product utilizes a different, non-infringing polymorph or form of the compound (Compl. ¶32).
    • Scope Question: For the '085 Patent, a potential claim construction dispute may arise over the phrase "characterized by the following major peaks." The court may need to determine if an accused product must exhibit all listed peaks, and how closely the relative intensities must match, to fall within the claim's scope.
    • Validity Question: The breadth of Claim 1 of the '070 Patent, which claims the compound without the specific XRPD limitations, raises the question of whether it is valid over prior art. Defendant's assertion of invalidity in its Paragraph IV certification may target this broad claim ('070 Patent, col. 10:52; Compl. ¶39).

V. Key Claim Terms for Construction

For the '085 Patent:

  • The Term: "trihydrate"
  • Context and Importance: This term is critical because the patent distinguishes the claimed invention from other forms, including a dihydrate ('085 Patent, col. 7:62-65). The infringement analysis will depend on whether Defendant’s product is in fact a trihydrate or another form. Practitioners may focus on this term to determine if Defendant's product, which might have a different water content or crystalline structure, falls outside the literal scope of the claim.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent does not provide significant evidence for an interpretation beyond its plain chemical meaning.
    • Evidence for a Narrower Interpretation: The specification repeatedly refers to the invention as a "well defined compound" and provides a detailed example of its preparation and analysis, distinguishing it from a dihydrate polymorph ('085 Patent, col. 2:15-16, col. 2:4-6, Example 1). This emphasis on a specific, distinct chemical entity may support a narrow construction limited to the precise form described.

For the '070 Patent:

  • The Term: "The magnesium salt of S-omeprazole trihydrate"
  • Context and Importance: This term constitutes the entirety of the independent claim, making its construction determinative of infringement and validity for this patent. The dispute will center on what chemical structures meet this definition and whether the claim should be limited to the specific crystalline form detailed in the specification.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself is broad and contains no process or structural limitations (e.g., XRPD peaks). This may suggest that the claim covers the compound regardless of its crystalline form.
    • Evidence for a Narrower Interpretation: A defendant may argue that the term should be limited by the specification's repeated emphasis on a single, "highly crystalline" form that is "more stable" than other forms ('070 Patent, col. 2:26-34, col. 2:48-49). This could be an attempt to import limitations from the specification to narrow the claim's scope and avoid infringement or a validity challenge.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that upon approval, Defendant will induce infringement by marketing its generic product. It states that administration to patients will occur at Defendant's "active behest and with their intent, knowledge, and encouragement," which points to inducement based on the product's labeling and instructions for use (Compl. ¶¶ 34, 41).
  • Willful Infringement: The complaint does not contain an explicit allegation of willful infringement. However, it pleads facts that could support such a claim for post-filing conduct by alleging that Defendant was put on notice of the patents-in-suit via the ANDA Notice Letter dated March 17, 2016 (Compl. ¶17).

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

  • A core issue will be one of factual proof: does the active ingredient in Defendant's proposed generic product have the specific crystalline structure, as defined by the X-ray diffraction peaks recited in the '085 patent, or does it utilize a chemically distinct, non-infringing polymorph?
  • A second key issue will be a question of claim scope versus validity for the '070 patent: can the broad claim to "The magnesium salt of S-omeprazole trihydrate" be interpreted to cover any form of the compound and remain valid over the prior art, or must it be construed narrowly in light of the specification's disclosure of a single, specific crystalline form?