DCT

2:19-cv-18555

Horizon Medicines LLC v. Ajanta Pharma Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:19-cv-18555, D.N.J., 09/30/2019
  • Venue Allegations: Venue is based on Defendant Ajanta Pharma USA, Inc. being a New Jersey corporation with its principal place of business in Bridgewater, NJ. The complaint alleges that both defendants conduct substantial and continuous business in the district, including the marketing and sale of generic drugs.
  • Core Dispute: Plaintiffs allege that Defendants' filing of an Abbreviated New Drug Application (ANDA) to market a generic version of VIMOVO® Delayed-Release Tablets constitutes an act of infringement of six U.S. patents related to pharmaceutical compositions for the coordinated delivery of an NSAID and an acid inhibitor.
  • Technical Context: The technology addresses the well-known gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) by combining an NSAID with an acid-inhibiting agent in a single dosage form that coordinates their release to protect the stomach lining.
  • Key Procedural History: This is an ANDA litigation initiated under the Hatch-Waxman Act, triggered by Defendants' filing of ANDA No. 213699 with a Paragraph IV certification. The complaint notes a concurrent action involving the same parties and patents filed in the District of Delaware, as well as prior litigation in the District of New Jersey involving the same patents against different generic manufacturers.

Case Timeline

Date Event
2001-06-01 Earliest Priority Date for all Patents-in-Suit
2014-10-07 U.S. Patent No. 8,852,636 Issues
2014-10-14 U.S. Patent No. 8,858,996 Issues
2015-10-20 U.S. Patent No. 9,161,920 Issues
2015-12-01 U.S. Patent No. 9,198,888 Issues
2016-05-24 U.S. Patent No. 9,345,695 Issues
2017-07-18 U.S. Patent No. 9,707,181 Issues
2019-09-30 Complaint Filed

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

U.S. Patent No. 9,345,695 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

The Invention Explained

  • Problem Addressed: The patent addresses the development of gastroduodenal lesions, such as ulcers and erosions, which can occur in individuals taking non-steroidal anti-inflammatory drugs (NSAIDs) for pain and inflammation (’695 Patent, col. 1:36-41). A major contributing factor is the presence of acid in the stomach and upper small intestine (’695 Patent, col. 1:41-44).
  • The Patented Solution: The invention is a unit dosage form that coordinates the release of two active agents. It first releases an acid inhibitor to raise the gastric pH to a safer level (e.g., above 3.5). Only after the pH is raised is the NSAID released from an enteric-coated core (’695 Patent, col. 3:9-21; Fig. 1). This sequential delivery is designed to minimize the NSAID's contact with the gastroduodenal mucosa while the environment is highly acidic, thereby reducing the risk of ulcers (’695 Patent, col. 3:12-21).
  • Technical Importance: This approach allows for the therapeutic benefits of NSAID treatment while mitigating one of its most significant and dose-limiting side effects, thereby improving patient safety and compliance (’695 Patent, col. 1:20-27).

Key Claims at a Glance

  • The complaint does not identify specific asserted claims, but Claim 1 is the sole independent claim.
  • Essential elements of Claim 1:
    • A pharmaceutical composition in unit dosage form comprising therapeutically effective amounts of esomeprazole and naproxen.
    • At least a portion of the esomeprazole is not surrounded by an enteric coating.
    • The naproxen is surrounded by a coating that inhibits its release unless the dosage form is in a medium with a pH of 3.5 or higher.
    • The coating comprises methacrylic acid copolymers.
    • The composition provides for release of esomeprazole such that upon introduction into a medium, at least a portion is released regardless of the pH.

U.S. Patent No. 8,852,636 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

The Invention Explained

  • Problem Addressed: The patent addresses the same technical problem as the ’695 Patent: NSAID-induced gastroduodenal damage due to the presence of stomach acid (’636 Patent, col. 1:36-44).
  • The Patented Solution: The patent describes a unit dosage form, such as a multilayer tablet, that achieves coordinated delivery of an acid inhibitor and an NSAID (’636 Patent, Abstract; Fig. 1). An outer layer containing the acid inhibitor (e.g., esomeprazole) dissolves immediately upon ingestion to raise the gastric pH. An inner core containing the NSAID (e.g., naproxen) is protected by a pH-sensitive enteric coating, which prevents the NSAID's release until the stomach environment is no longer highly acidic (’636 Patent, col. 12:47-65).
  • Technical Importance: This coordinated release mechanism provides a gastroprotective effect, allowing patients to receive anti-inflammatory and analgesic treatment with a reduced risk of gastrointestinal damage like ulcers and erosions (’636 Patent, Abstract).

Key Claims at a Glance

  • The complaint does not identify specific asserted claims, but Claim 1 is a representative independent claim.
  • Essential elements of Claim 1:
    • A pharmaceutical composition in unit dose form suitable for oral administration.
    • Comprising esomeprazole in an amount effective to raise gastric pH to at least 3.5.
    • Comprising naproxen in an amount effective to reduce pain or inflammation.
    • The composition is a tablet with naproxen in a core.
    • The tablet has a coating surrounding the core that does not release naproxen until the pH is 3.5 or higher.
    • Esomeprazole is in one or more layers outside the core, which are not surrounded by an enteric coating and release upon ingestion.

U.S. Patent No. 8,858,996 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

  • Patent Identification: U.S. Patent No. 8,858,996, entitled "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs", issued October 14, 2014.
  • Technology Synopsis: This patent covers a pharmaceutical tablet for oral administration that contains naproxen and esomeprazole. The invention is structured to release the esomeprazole regardless of pH, while a coating inhibits the release of the naproxen core until the surrounding pH is 3.5 or higher, thereby protecting the gastrointestinal tract (’996 Patent, col. 21:23-34).
  • Asserted Claims: Independent Claim 1.
  • Accused Features: The entirety of Defendants' ANDA Product, which is alleged to be a generic equivalent of VIMOVO®, is accused of infringement (Compl. ¶¶95-96).

U.S. Patent No. 9,161,920 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

  • Patent Identification: U.S. Patent No. 9,161,920, entitled "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs", issued October 20, 2015.
  • Technology Synopsis: This patent claims a method of reducing the incidence of NSAID-associated gastric ulcers by administering a pharmaceutical composition containing naproxen and esomeprazole. The composition is formulated as a tablet where the naproxen core is coated to prevent release below a pH of 3.5, while the esomeprazole is released immediately to raise gastric pH (’920 Patent, col. 21:12-29).
  • Asserted Claims: Independent Claims 1 and 11.
  • Accused Features: The intended use of Defendants' ANDA Product to treat conditions like osteoarthritis and rheumatoid arthritis is accused of infringing the claimed methods (Compl. ¶¶117-118).

U.S. Patent No. 9,198,888 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

  • Patent Identification: U.S. Patent No. 9,198,888, entitled "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs", issued December 1, 2015.
  • Technology Synopsis: This patent is directed to a pharmaceutical composition in a unit dosage form containing naproxen and esomeprazole. The claims specify that the esomeprazole is released regardless of pH, while the naproxen is surrounded by a coating that prevents its release until the ambient pH is at least 3.5, thereby providing gastroprotection (’888 Patent, col. 21:28-40).
  • Asserted Claims: Independent Claim 1.
  • Accused Features: Defendants' ANDA Product as a whole is accused of infringing the claimed composition (Compl. ¶¶139-140).

U.S. Patent No. 9,707,181 - "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs"

  • Patent Identification: U.S. Patent No. 9,707,181, entitled "Pharmaceutical Compositions for the Coordinated Delivery of NSAIDs", issued July 18, 2017.
  • Technology Synopsis: This patent covers a pharmaceutical composition comprising naproxen and esomeprazole in a multilayer tablet. The claims require the esomeprazole to be located in one or more layers outside a naproxen core, and for the naproxen core to be surrounded by a coating that inhibits its release until the pH is 3.5 or higher (’181 Patent, col. 21:10-30).
  • Asserted Claims: Independent Claim 1.
  • Accused Features: Defendants' ANDA Product, alleged to be a generic version of the multilayer VIMOVO® tablet, is accused of infringing the claimed structure (Compl. ¶¶161-162).

III. The Accused Instrumentality

Product Identification

  • Defendants' naproxen and esomeprazole magnesium delayed-release tablets, for which Defendants filed ANDA No. 213699 seeking FDA approval for commercial manufacture and sale in the United States (Compl. ¶26).

Functionality and Market Context

  • The accused instrumentality is a generic version of Plaintiffs' VIMOVO® tablets, offered in 375 mg/20 mg and 500 mg/20 mg (naproxen/esomeprazole magnesium) strengths (Compl. ¶26). It is a prescription drug intended to relieve the signs and symptoms of arthritis and to decrease the risk of gastric ulcers from treatment with NSAIDs (Compl. ¶7). The complaint alleges that the ANDA Product contains the same active ingredients and is intended for the same uses as VIMOVO®, implying it possesses the same coordinated-release functionality as the patented invention (Compl. ¶¶51, 73, 95, 117, 139, 161). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not provide claim charts or detailed infringement contentions. The infringement theory is based on the allegation that Defendants' ANDA filing for a generic equivalent of VIMOVO® constitutes an act of infringement under 35 U.S.C. § 271(e)(2), as the product described in the ANDA will necessarily meet the limitations of the asserted claims upon approval and commercialization.

U.S. Patent No. 9,345,695 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A pharmaceutical composition in unit dosage form comprising therapeutically effective amounts of...esomeprazole...and naproxen The ANDA Product is a unit dosage form tablet containing therapeutically effective amounts of esomeprazole magnesium and naproxen. ¶26 col. 21:49-53
wherein at least a portion of said esomeprazole is not surrounded by an enteric coating The ANDA Product, as a generic of VIMOVO®, is alleged to have an immediate-release component of esomeprazole designed to act first in the stomach. ¶¶26, 51, 58 col. 12:47-54
and wherein said naproxen is surrounded by a coating that inhibits its release from said unit dosage form unless said dosage form is in a medium with a pH of 3.5 or higher The ANDA Product is alleged to have a delayed-release naproxen core with a pH-sensitive coating that prevents release in a highly acidic environment. ¶¶26, 51, 58 col. 12:55-65
wherein said coating comprises methacrylic acid copolymers The ANDA Product is alleged to utilize a pH-sensitive enteric coating material that falls within this class of polymers. ¶¶26, 51, 58 col. 14:35-45

U.S. Patent No. 8,852,636 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A pharmaceutical composition in unit dose form...said unit dosage form is a tablet in which said naproxen is present in a core; The ANDA Product is a unit dosage form tablet alleged to contain a core comprising naproxen. ¶¶26, 73, 80 col. 12:47-51
said tablet comprises a coating, wherein said coating surrounds said core...and does not release said naproxen until the pH of the surrounding medium is 3.5 or higher; The ANDA Product is alleged to have a pH-sensitive enteric coating over the naproxen core that prevents release in highly acidic conditions. ¶¶26, 73, 80 col. 12:55-61
and said esomeprazole is in one or more layers outside said core, wherein said one or more layers: A) do not include an naproxen; B) are not surrounded by an enteric coating; and C) upon ingestion...release said esomeprazole into said patient's stomach. The ANDA Product, as a generic of VIMOVO®, is alleged to have one or more immediate-release layers of esomeprazole outside the coated naproxen core. ¶¶26, 73, 80 col. 12:47-54

Identified Points of Contention

  • Scope Questions: A primary question will be whether the specific formulation of the Defendants' ANDA product meets every limitation of the asserted claims. For instance, does the term "inhibits its release...unless said dosage form is in a medium with a pH of 3.5 or higher" read on the in vitro dissolution profile and in vivo performance of the specific enteric coating used in the ANDA product?
  • Technical Questions: What evidence exists that the specific methacrylic acid copolymers and other excipients used in the ANDA product function in the precise manner required by the claims? The case may turn on expert analysis of the ANDA filing's chemistry, manufacturing, and controls (CMC) section to determine if the generic product's formulation and release mechanism are identical to those claimed, or merely bioequivalent.

V. Key Claim Terms for Construction

  • The Term: "inhibits its release...unless said dosage form is in a medium with a pH of 3.5 or higher" (’695 Patent, Claim 1; ’636 Patent, Claim 1).
  • Context and Importance: This term is central to the invention's coordinated-release mechanism. The infringement analysis will depend on the precise dissolution characteristics required to meet this limitation. Practitioners may focus on whether this requires a sharp, switch-like dissolution at pH 3.5 or allows for a more gradual onset of release around that pH, and what level of "inhibition" is required below pH 3.5.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification discusses the goal of preventing NSAID release until the pH is raised, suggesting the specific numeric value may be an exemplary threshold rather than a rigid, absolute trigger (’636 Patent, col. 3:12-21). The claims use the open-ended term "higher," which may support a construction covering any coating that begins to dissolve at or above pH 3.5.
    • Evidence for a Narrower Interpretation: The patent repeatedly and consistently recites the 3.5 pH value, suggesting its importance (’636 Patent, col. 12:59-61; col. 22:10-12). Specific examples of enteric coating materials are provided, which could be used to argue that the claims are limited to coatings with dissolution profiles characteristic of those specific polymers, such as certain Eudragit® copolymers (’636 Patent, col. 15:7-22).

VI. Other Allegations

  • Indirect Infringement: The complaint includes declaratory judgment counts asserting infringement under 35 U.S.C. §§ 271(b) and (c) (Compl. ¶¶59, 81, 103, 125, 147, 169). The basis for these allegations is that Defendants, by seeking FDA approval, intend for their ANDA Product to be used in accordance with its labeling for the same patented indications as VIMOVO®, which would induce physicians and patients to infringe the method claims.
  • Willful Infringement: The complaint does not contain specific allegations of willful infringement.

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

  • A core issue will be one of claim scope and chemical formulation: Does the specific combination of polymers, plasticizers, and other excipients described in Defendants' ANDA No. 213699 result in a product that meets every limitation of the asserted composition claims? The dispute will likely focus on whether the generic formulation is merely bioequivalent or is a precise replica of the claimed pharmaceutical structure and composition.
  • A key evidentiary question will be one of functional performance: Can Plaintiffs demonstrate, based on the contents of the ANDA and potentially laboratory testing, that Defendants' product exhibits the specific pH-dependent dissolution profile required by the claim term "inhibits its release...unless said dosage form is in a medium with a pH of 3.5 or higher"? The case will likely hinge on a technical comparison of the release kinetics of the generic product against the boundaries established by claim construction.