DCT

3:19-cv-22193

Actelion Pharma Ltd v. Zydus Pharma USA Inc

Log In

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 3:19-cv-22193, D.N.J., 12/31/2019
  • Venue Allegations: Venue is alleged to be proper over Zydus Pharmaceuticals (USA) Inc. because it is incorporated in New Jersey and maintains a regular and established place of business in the district. Venue over foreign entity Cadila Healthcare Ltd. is asserted on the basis that it may be sued in any judicial district where it is subject to the court's personal jurisdiction.
  • Core Dispute: Plaintiff alleges that Defendant’s proposed generic version of TRACLEER®, the subject of an Abbreviated New Drug Application, infringes a patent related to a dispersible tablet formulation of the drug bosentan.
  • Technical Context: The dispute concerns pharmaceutical formulations of bosentan, a treatment for pulmonary arterial hypertension, specifically a tablet designed to be dispersed in water for easier administration, particularly to pediatric patients.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendants' submission of an Abbreviated New Drug Application (ANDA) to the FDA. The ANDA submission included a "Paragraph IV" certification asserting that the patent-in-suit is invalid, unenforceable, or will not be infringed by the proposed generic product. The patent is listed in the FDA's "Orange Book" for Plaintiff's TRACLEER® product. This lawsuit was filed within the 45-day statutory window, triggering a potential 30-month stay on FDA approval of the Defendants' ANDA.

Case Timeline

Date Event
2005-05-17 ’126 Patent Priority Date
2012-11-13 ’126 Patent Issue Date
2019-11-19 Date of Zydus Notice Letter
2019-11-21 Plaintiff receives Zydus Notice Letter (approx.)
2019-12-31 Complaint Filing Date

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

  • Patent Identification: U.S. Patent No. 8,309,126, “Dispersible Bosentan Tablet,” issued November 13, 2012. (Compl. ¶11).

The Invention Explained

  • Problem Addressed: The patent's background section notes that conventional tablet formulations are not convenient for administration to children, who often have difficulty swallowing solid pills (’126 Patent, col. 4:1-3).
  • The Patented Solution: The invention is a dispersible tablet containing the active ingredient bosentan, which is designed to disintegrate in water to form a suspension prior to administration (’126 Patent, col. 4:5-8). This approach creates a "children-friendly" dosage form. The specification further describes that the presence of an acidifying agent can decrease the solubility of the bitter-tasting bosentan, thereby preventing an unpleasant taste when the tablet is dispersed in water before administration (’126 Patent, col. 5:38-42).
  • Technical Importance: The development of a pediatric-friendly formulation allows for more "optimized and individualized dosing according to body weight" and is intended to improve patient compliance, particularly in pediatric populations (’126 Patent, col. 4:19-22).

Key Claims at a Glance

  • The complaint asserts claims "including but not limited to Claims 4, 6, and 8" (Compl. ¶50). These claims depend on independent claim 1.
  • Independent Claim 1:
    • A dispersible tablet composition
    • comprising an active ingredient consisting of compound I (bosentan) or a pharmaceutically acceptable salt or solvate thereof,
    • and pharmaceutically acceptable excipients.
  • The complaint also notes that Defendants allegedly do not deny infringement of claims 1-4, 6, 8, 10, and 11 apart from their invalidity defense (Compl. ¶51).

III. The Accused Instrumentality

Product Identification

  • The accused instrumentality is the "Zydus ANDA Product," identified as a generic version of TRACLEER® (bosentan) 32 mg dispersible tablets for oral suspension, for which Defendants have submitted Abbreviated New Drug Application (ANDA) No. 213981 to the FDA (Compl. ¶¶8, 16).

Functionality and Market Context

  • The complaint alleges the Zydus ANDA Product is a "generic version" of Plaintiffs' TRACLEER® product, which is indicated for the treatment of pediatric patients with pulmonary arterial hypertension (Compl. ¶¶14, 16). The act of infringement alleged is the submission of the ANDA seeking FDA approval to commercially manufacture, use, and sell this product in the United States prior to the expiration of the ’126 Patent (Compl. ¶17). The complaint does not provide specific technical details regarding the composition or manufacturing process of the Zydus ANDA Product, as these details are contained within the confidential ANDA submission.

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

The complaint does not contain a claim chart or provide a detailed, element-by-element analysis of infringement. The infringement allegations are premised on the statutory act of infringement under 35 U.S.C. § 271(e)(2), which defines the submission of an ANDA seeking approval to market a generic version of a patented drug as an act of infringement (Compl. ¶52). The complaint makes the conclusory allegation that the "use of Zydus' ANDA Product is covered by one or more claims of the '126 patent, including but not limited to Claims 4, 6, and 8" (Compl. ¶50).

  • Identified Points of Contention: The core of the dispute, as framed by the complaint, arises from Defendants' Paragraph IV certification asserting non-infringement and/or invalidity of the ’126 patent (Compl. ¶18).
    • Scope Questions: A central issue will be whether the specific formulation detailed in Zydus's confidential ANDA falls within the scope of the asserted claims. For instance, a dispute may arise over whether the accused product meets the patent’s definition of a "dispersible tablet," which the specification describes as a tablet that "disintegrates completely in water at 15-22° C. in not more than 5 minutes" (’126 Patent, col. 4:57-60; col. 8:50-52).
    • Technical Questions: The case will likely involve a technical comparison between the excipients used in the Zydus ANDA Product and the elements of the asserted dependent claims. For example, should Plaintiff press claim 4, a key question for the court may be whether the accused product contains an "acidifying agent" that performs the taste-masking function described in the patent (’126 Patent, col. 5:38-42).

V. Key Claim Terms for Construction

  • The Term: "dispersible tablet"
  • Context and Importance: This term appears in the preamble of independent claim 1 and is fundamental to the invention. The outcome of the non-infringement analysis could depend heavily on whether the Zydus ANDA Product is properly characterized as a "dispersible tablet" as the patent construes the term.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A party might argue that the term should be given its plain and ordinary meaning in the pharmaceutical arts, as the body of claim 1 itself does not contain an explicit structural or functional definition.
    • Evidence for a Narrower Interpretation: The specification provides a clear, functional definition, stating that a "dispersible tablet" is a tablet "which disintegrates completely in water at 15-22° C. in not more than 5 minutes" (’126 Patent, col. 4:56-60). This language, along with dependent claim 11 which recites this exact limitation (’126 Patent, col. 8:50-52), provides strong intrinsic evidence that the patentee may have intended to act as its own lexicographer, thereby narrowing the scope of the term.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges active inducement and contributory infringement (Compl. ¶53). The inducement allegation is based on the assertion that Defendants' proposed product labeling will instruct users to infringe the ’126 patent (Compl. ¶54). The contributory infringement allegation is based on the assertion that the Zydus ANDA Product and its labeling are "especially made or adapted for use in infringing the '126 patent" and are "not suitable for any substantial noninfringing use" (Compl. ¶57).
  • Willful Infringement: The complaint alleges that Defendants "have knowledge of the '126 patent and will be knowingly and willfully infringing" it (Compl. ¶59). This allegation is supported by the fact that Defendants submitted a Paragraph IV certification with respect to the ’126 patent and sent a notice letter to Plaintiffs, which demonstrates pre-suit knowledge (Compl. ¶¶16, 20).

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

This Hatch-Waxman litigation will likely focus on the two central pillars of patent disputes: non-infringement and invalidity. The resolution of the case may turn on the answers to the following questions:

  • A central question of non-infringement will be one of formulation equivalence: Does the specific combination of active ingredient and excipients in the confidential Zydus ANDA product meet all limitations of the asserted claims, particularly the functional requirements for a "dispersible tablet" as defined within the ’126 patent's specification?
  • A key issue will concern validity: Given the apparent breadth of independent claim 1, which claims a "dispersible tablet" of bosentan with "pharmaceutically acceptable excipients," a primary question for the court will be whether Defendants can prove by clear and convincing evidence that this claimed composition was anticipated or rendered obvious by prior art pharmaceutical formulation techniques existing before May 2005.