DCT

2:18-cv-02065

Sumitomo Dainippon Pharma Co Ltd v. Emcure Pharma Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:18-cv-02065, D.N.J., 06/08/2018
  • Venue Allegations: Plaintiffs allege venue is proper in the District of New Jersey because Defendant committed an act of infringement in the district by submitting its Abbreviated New Drug Application (ANDA) to the FDA, and upon approval, intends to market its generic product in the state.
  • Core Dispute: Plaintiffs allege that Defendant's submission of an ANDA to market a generic version of the antipsychotic drug Latuda® constitutes an act of infringement of patents covering methods of treatment that avoid weight gain and specific pharmaceutical compositions of the drug.
  • Technical Context: The technology concerns atypical antipsychotic drugs for treating schizophrenia and bipolar disorder, with a focus on methods and formulations designed to improve patient outcomes by minimizing common side effects like weight gain and ensuring consistent drug delivery across various dosage strengths.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following Defendant’s submission of ANDA No. 208058, which seeks FDA approval to market a generic version of Plaintiffs’ Latuda® product. The complaint states that the asserted patents are listed in the FDA’s Orange Book for Latuda®, and that Plaintiffs filed suit within the 45-day statutory window after receiving Defendant's Paragraph IV certification notice letters. The FDA has granted tentative approval to Defendant's ANDA.

Case Timeline

Date Event
2002-08-22 U.S. Patent No. 9,815,827 Priority Date
2005-05-26 U.S. Patent No. 9,907,794 Priority Date
2017-11-14 U.S. Patent No. 9,815,827 Issued
2018-01-08 Plaintiff Sunovion receives '827 Patent Notice Letter
2018-01-09 Plaintiff Sumitomo receives '827 Patent Notice Letter
2018-03-06 U.S. Patent No. 9,907,794 Issued
2018-06-06 Plaintiff Sunovion receives '794 Patent Notice Letter
2018-06-08 Plaintiff Sumitomo receives '794 Patent Notice Letter
2018-06-08 First Amended Complaint Filed

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

U.S. Patent No. 9,815,827 - Agent for Treatment of Schizophrenia, issued November 14, 2017

The Invention Explained

  • Problem Addressed: The patent notes that while medications are used to treat psychotic symptoms, conventional antipsychotic drugs are known to cause serious side effects, with weight gain being a well-known example (Compl. ¶¶ 18-19; ’827 Patent, col. 1:57-63). There exists a need for effective antipsychotics that do not cause such undesirable side effects (Compl. ¶22).
  • The Patented Solution: The invention is a method of treatment using the compound lurasidone. It discloses that by orally administering a specific daily dose of lurasidone (20 mg to 120 mg) as the sole active ingredient, a patient can be treated for conditions like schizophrenia without experiencing a clinically significant weight gain, including after six weeks of administration (Compl. ¶29; ’827 Patent, col. 7:55-65). The invention is premised on the discovery of this specific therapeutic window and its advantageous side-effect profile, which the complaint alleges was not a well-understood or conventional technique (Compl. ¶29).
  • Technical Importance: An antipsychotic treatment that avoids weight gain can improve patient health outcomes and adherence to long-term therapy, a critical factor in managing chronic conditions like schizophrenia (’827 Patent, col. 2:1-4).

Key Claims at a Glance

  • The complaint identifies independent claim 40 as illustrative (Compl. ¶30).
  • Essential elements of claim 40 include:
    • A method of treating a patient with an antipsychotic without a clinically significant weight gain, comprising:
    • orally administering once daily to the patient a pharmaceutical composition comprising 20 to 120 mg of lurasidone or a pharmaceutically acceptable salt thereof as the sole active ingredient;
    • such that the patient does not experience a clinically significant weight gain.
  • The complaint also recites dependent claim 43, which adds the limitation that the patient does not experience clinically significant weight gain "after six weeks of administration" (Compl. ¶30).

U.S. Patent No. 9,907,794 - Pharmaceutical Composition, issued March 6, 2018

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of creating oral drug formulations for slightly water-soluble active ingredients like lurasidone. Specifically, it highlights the difficulty in developing formulations that exhibit rapid and equivalent dissolution across a wide range of dosage strengths, a requirement for ensuring bioequivalence and simplifying patient dosing regimens (’794 Patent, col. 1:42-54, col. 2:5-23).
  • The Patented Solution: The patent discloses a specific tablet formulation that solves this problem. The solution lies in a composition comprising lurasidone, a "pregelatinized starch," a water-soluble excipient (like mannitol), a water-soluble polymer binder, and a lubricant (’794 Patent, col. 3:2-19). This combination of ingredients is asserted to provide a rapid and consistent dissolution profile, even as the dosage of the active ingredient is varied across tablets of different strengths (’794 Patent, col. 7:44-54).
  • Technical Importance: This formulation technology enables the creation of a family of drug products (e.g., 20 mg, 40 mg, 80 mg tablets) that are bioequivalent on a dose-adjusted basis, which is crucial for both clinical flexibility and streamlined regulatory pathways (’794 Patent, col. 2:40-54).

Key Claims at a Glance

  • The complaint identifies independent claims 1 and 15 as illustrative (Compl. ¶44).
  • Essential elements of claim 1 include:
    • A tablet for oral administration comprising: 20 to 120 mg of lurasidone, a pregelatinized starch, a water-soluble excipient, a water-soluble polymer binder, and a lubricant.
    • A specific content ratio of lurasidone (20 to 45% wt/wt).
    • A dissolution rate of 80% or more at 30 minutes under specified test conditions.
    • A "similar dissolution profile" to a second tablet with a different lurasidone content, where similarity is defined by a similarity factor "f2 value of 50 or more" and other criteria.

III. The Accused Instrumentality

Product Identification

Defendant Emcure's "Proposed ANDA Product" is a generic version of lurasidone hydrochloride tablets, intended for marketing in 20 mg, 40 mg, 60 mg, 80 mg, and 120 mg strengths (Compl. ¶45, 63).

Functionality and Market Context

The product is an atypical antipsychotic drug intended for the same therapeutic uses as the branded drug, Latuda®, namely the treatment of schizophrenia and depressive episodes associated with bipolar I disorder (Compl. ¶50). As a generic product submitted via an ANDA, it is intended to be a bioequivalent copy of Latuda® (Compl. ¶8, 45). The complaint alleges that the proposed label for Emcure's product will instruct for these uses and will contain data relating to patient weight gain derived from clinical studies of Latuda® (Compl. ¶¶ 50-51).

IV. Analysis of Infringement Allegations

'827 Patent Infringement Allegations

Claim Element (from Independent Claim 40) Alleged Infringing Functionality Complaint Citation Patent Citation
A method of treating a patient with an antipsychotic without a clinically significant weight gain, comprising: Defendant's proposed product label will allegedly instruct physicians to administer the drug to treat schizophrenia and manic depressive psychosis, and will include data showing a lack of clinically significant weight gain. ¶52 col. 10:50-58
orally administering once daily to the patient a pharmaceutical composition comprising 20 to 120 mg of ... lurasidone or a pharmaceutically acceptable salt thereof as the sole active ingredient Defendant's product is a generic lurasidone hydrochloride tablet offered in 20, 40, 60, 80, and 120 mg strengths. The proposed label will allegedly instruct once-daily administration. ¶50 col. 10:59-65
such that the patient does not experience a clinically significant weight gain. The complaint alleges that Defendant's proposed label will contain clinical data demonstrating that patients taking the product will not experience clinically significant weight gain. This is supported by visual evidence in the complaint. Table 9 from the Latuda® Prescribing Information, included in the complaint, shows mean weight change data for adult schizophrenia patients, comparing various doses of Latuda® to a placebo over a six-week period. ¶37, ¶51, ¶52 col. 10:65-67

'794 Patent Infringement Allegations

The complaint does not provide a detailed, element-by-element infringement analysis for the ’794 patent. The infringement theory is based on the allegation that for Defendant's product to be approved as a bioequivalent generic, it must necessarily possess the formulation and performance characteristics claimed in the ’794 patent (Compl. ¶¶ 45, 60). Plaintiffs state they have obtained a copy of the Defendant's ANDA, which would contain the specific formulation, but these details are not pleaded in the complaint (Compl. ¶59). The core allegation is that the accused product will infringe by containing the claimed combination of lurasidone, a pregelatinized starch, a water-soluble excipient, a binder, and a lubricant, and will exhibit the claimed dissolution and f2 similarity profiles (Compl. ¶¶ 44, 60).

  • Identified Points of Contention:
    • Scope Questions ('827 Patent): The case may raise the question of whether a method claim defined by achieving a desired result (treatment) while avoiding an undesirable one ("without a clinically significant weight gain") claims a patent-eligible invention or merely an inherent, natural consequence of using a known drug at a known therapeutic dose.
    • Technical Questions ('794 Patent): A primary point of dispute will likely be factual: does the formulation detailed in Defendant's confidential ANDA literally meet every limitation of the asserted claims? Specifically, this will involve analysis of whether the accused product contains "pregelatinized starch" as claimed and whether it meets the quantitative dissolution and f2 similarity requirements across its different dosage strengths.

V. Key Claim Terms for Construction

  • For the ’827 Patent:

    • The Term: "clinically significant weight gain"
    • Context and Importance: This negative limitation is the central feature of the asserted method claims. The outcome of the infringement and validity analyses will depend heavily on its construction. Practitioners may focus on this term because its potential ambiguity could be a basis for an indefiniteness challenge under 35 U.S.C. § 112.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The patent specification does not provide a precise numerical definition for the term, instead discussing weight gain as a general "serious side effect" of conventional antipsychotics (’827 Patent, col. 1:57-63). This could support a more flexible, context-dependent interpretation based on a physician's judgment.
      • Evidence for a Narrower Interpretation: The patent's clinical trial data, presented in tables and a figure, shows specific, small mean weight changes (e.g., Table 2 shows a -11.3 kg change in BPRS score with minimal weight gain). Parties may argue the term should be limited by the magnitude of weight gain observed in the patent's own successful embodiments (’827 Patent, FIG. 1, Tables 2-5).

  • For the ’794 Patent:

    • The Term: "pregelatinized starch"
    • Context and Importance: This excipient is presented as a key component for achieving the invention's goal of consistent dissolution. Whether Defendant's product contains this specific type of starch, as opposed to another binder or a different form of starch, will be critical to the infringement analysis.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification states the term "may include pregelatinized starch or partly pregelatinized starch described in Japanese Pharmaceutical Excipients," suggesting it is not limited to a single chemical entity but a class of materials (’794 Patent, col. 5:32-35).
      • Evidence for a Narrower Interpretation: The specification identifies specific commercial examples like "PCS...or Starch 1500" and describes preferred properties, such as a "pregelatinization ratio...in the range of 80 to 95%" (’794 Patent, col. 5:46-53). A party could argue the term should be construed to require these specific properties.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges induced infringement of the ’827 patent, stating that Defendant’s proposed product label will instruct and encourage physicians and healthcare providers to administer the generic product in a manner that directly infringes the patented methods (Compl. ¶¶ 53, 83-86).
  • Willful Infringement: The complaint alleges that Defendant had knowledge of the ’827 patent, at the latest, upon its issuance and listing in the Orange Book, and that its continued activities toward marketing an infringing product constitute willful infringement (Compl. ¶¶ 78, 96). The Paragraph IV notice letter is also evidence of pre-suit knowledge of the patent.

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

  • A core issue will be one of inherency and patent eligibility: Can the '827 patent's method claims, which are defined by the absence of a negative side effect ("without a clinically significant weight gain"), survive challenges that they merely claim an inherent property of a known drug administered at a therapeutic dosage?
  • A key dispute will be one of claim construction and definiteness: The infringement and validity analysis for the '827 patent will likely turn on whether the court can construe the term "clinically significant weight gain" with sufficient objective clarity to be enforceable, a term not explicitly defined with a numerical boundary in the patent.
  • A central evidentiary question will be one of technical and factual infringement: The case for the '794 patent will depend on a direct comparison between the patent's formulation claims and the confidential details of Defendant's ANDA. This will focus on whether the accused product's composition and performance data (e.g., its use of "pregelatinized starch" and its f2 similarity values) fall within the literal scope of the claims.