DCT

1:25-cv-01507

Azurity Pharma Inc v. Aurobindo Pharma Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:25-cv-01507, D. Del., 12/15/2025
  • Venue Allegations: Plaintiffs allege venue is proper in the District of Delaware based on statutory grounds for patent cases. Personal jurisdiction is asserted based on Defendant's intent to market its generic products in Delaware and its history of consenting to jurisdiction in prior Delaware litigation.
  • Core Dispute: Plaintiffs allege that Defendant’s submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of the hypertension drug EDARBI® constitutes an act of patent infringement under the Hatch-Waxman Act.
  • Technical Context: The lawsuit concerns a pharmaceutical formulation for azilsartan, an angiotensin II receptor antagonist used to treat hypertension, focusing on a method to improve the drug's stability and dissolution properties in a solid oral tablet.
  • Key Procedural History: This action was initiated under the Hatch-Waxman framework following Plaintiffs' receipt of a notice letter regarding Defendant's ANDA filing, which included a Paragraph IV certification asserting that the patent-in-suit is invalid, unenforceable, or would not be infringed. The complaint notes the action was filed within the 45-day statutory window.

Case Timeline

Date Event
2007-03-28 '936 Patent Priority Date
2015-06-30 '936 Patent Issue Date
2025-10-31 Date of Defendant's ANDA Notice Letter
2025-12-15 Complaint Filing Date

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

U.S. Patent No. 9,066,936 - Solid Pharmaceutical Composition Comprising a Benzimidazole-7-Carboxylate Derivative and a pH Control Agent

Issued June 30, 2015

The Invention Explained

  • Problem Addressed: The patent addresses a fundamental challenge in formulating a specific benzimidazole derivative (the active ingredient, "compound (I)"). This compound is unstable at the neutral pH levels typical for pharmaceutical preparations, but it has very low solubility at the acidic pH levels where it is stable (’936 Patent, col. 2:6-12). This creates a dilemma: a stable formulation may not dissolve effectively in the body, and a dissolvable formulation may not be stable on the shelf.
  • The Patented Solution: The invention is a solid pharmaceutical composition that combines the active ingredient with a "pH control agent" (’936 Patent, col. 1:15-19). The inventors found that the co-presence of a specific type of pH control agent—one that creates an acidic environment (pH 3 to 5) when dissolved in water—unexpectedly solves both problems, yielding a composition that is superior in both stability and dissolution properties (’936 Patent, Abstract; col. 2:26-34).
  • Technical Importance: This approach provides a method to formulate an otherwise difficult compound into a viable solid oral dosage form, enabling its use as a therapeutic for conditions like hypertension (’936 Patent, col. 2:1-6).

Key Claims at a Glance

The complaint does not specify which claims of the '936 Patent it asserts, stating only that Defendant has infringed "one or more claims" (Compl., Prayer for Relief ¶A). Independent claim 1 is a composition claim and is central to the patent.

  • Independent Claim 1:
    • A solid pharmaceutical composition comprising a compound which is (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl 2-ethoxy-1-{[2'-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl}-1H-benzimidazole-7-carboxylate potassium salt
    • and a solid pH control agent which provides a pH of 3 to 5 when dissolved or suspended in water at a concentration of 1% w/v at 25° C.

III. The Accused Instrumentality

Product Identification

  • Defendant’s generic oral tablets containing azilsartan medoxomil in 40 mg and 80 mg dosages, as described in ANDA No. 220957 (“the ANDA Products”) (Compl. ¶18).

Functionality and Market Context

  • The ANDA Products are generic versions of Plaintiffs’ branded EDARBI® tablets (Compl. ¶16). The complaint alleges that by filing the ANDA, Defendant has represented to the FDA that its products have the same active ingredient, dosage form, strength, and route of administration as EDARBI®, and are bioequivalent to it (Compl. ¶¶19, 25). The filing of the ANDA seeks FDA approval for commercial sale of the ANDA Products in the United States prior to the expiration of the ’936 Patent (Compl. ¶18).

IV. Analysis of Infringement Allegations

The complaint does not provide a detailed, element-by-element mapping of the asserted claims to the accused ANDA Products. The central allegation is that Defendant's submission of ANDA No. 220957, which seeks approval to market a generic version of EDARBI®, constitutes a technical act of infringement under 35 U.S.C. § 271(e)(2)(A) (Compl. ¶28). The infringement theory appears to rest on the assertion that for the ANDA product to be bioequivalent to EDARBI®, it must necessarily possess the characteristics of the claimed composition. The complaint alleges that the future commercial manufacture and sale of the ANDA Products, if approved, would constitute direct and indirect infringement (Compl. ¶29).

No probative visual evidence provided in complaint.

  • Identified Points of Contention:
    • Compositional Questions: The primary technical question will be whether the specific formulation detailed in Defendant's confidential ANDA contains both the claimed active ingredient and a "pH control agent" that meets the functional requirements of the asserted claims. The identity and properties of the excipients used in the generic formulation will be the central factual dispute.
    • Scope Questions: A likely point of contention is whether an excipient in the ANDA product, which may have other primary functions (e.g., as a binder or filler), can also be classified as a "pH control agent" as that term is used in the patent.

V. Key Claim Terms for Construction

  • The Term: "pH control agent"

    • Context and Importance: This term is the central inventive element differentiating the claimed composition from the prior art. Its construction will determine whether any of the excipients in Defendant's generic formulation fall within the scope of the claims.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification states that "any pH control agent can be used as long as it can simultaneously achieve the stability of compound (I) in a drug product and dissolution property thereof" (’936 Patent, col. 5:63-66). This language may support a broad, functional definition not limited to specific chemical classes.
      • Evidence for a Narrower Interpretation: The specification provides a list of "preferable examples," including "monosodium fumarate" and a "combination of fumaric acid and sodium hydroxide" (’936 Patent, col. 6:36-42). Defendant may argue that the term should be construed more narrowly to cover only substances with known pH-buffering capabilities or those similar to the disclosed examples.

  • The Term: "provides a pH of 3 to 5 when dissolved or suspended in water at a concentration of 1% w/v at 25° C."

    • Context and Importance: This phrase sets the specific functional requirement for the "pH control agent." The dispute will likely focus on whether this is merely a test performed on the agent in isolation or if it implies a functional role within the final drug product.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The claim language presents a straightforward, objective test for an ingredient. Plaintiffs may argue that if an excipient used by Defendant meets this standalone test, it satisfies the limitation, regardless of the final tablet's overall pH.
      • Evidence for a Narrower Interpretation: Defendant may argue that this property must be tied to the agent's purpose and effect within the composition itself, suggesting that the "pH control" function must be operative in the solid dosage form, not just in a laboratory water suspension. The patent's objective is to stabilize "compound (I) in a preparation" (’936 Patent, col. 2:27-28).

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendant’s future commercial activities, if its ANDA is approved, would induce infringement by others and contribute to infringement, based on the product's use in accordance with its proposed labeling (Compl. ¶29).
  • Willful Infringement: The complaint alleges that Defendant had "actual and constructive knowledge" of the ’936 Patent before submitting its ANDA and had "specific intent to infringe" when it filed the application (Compl. ¶¶30-31). These allegations form the basis for a claim of willfulness.

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

  • A central factual issue will be one of compositional identity: Does the specific formulation disclosed in Defendant's confidential ANDA contain an excipient that qualifies as a "pH control agent" by providing "a pH of 3 to 5" under the test conditions specified in claim 1? The outcome will depend entirely on the evidence obtained from the ANDA during discovery.
  • The key legal question will be one of definitional scope: How will the court construe the term "pH control agent"? The case may turn on whether the term is interpreted broadly to cover any substance with the claimed pH effect, or more narrowly to require a substance whose primary purpose is pH modification or that is structurally similar to the patent's examples.