DCT

1:25-cv-01262

Bayer Healthcare Pharma Inc v. Apotex Inc

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:25-cv-01262, D. Del., 10/15/2025
  • Venue Allegations: Venue is alleged to be proper as to Defendant Apotex Corp. because it is a Delaware corporation. Venue over Defendant Apotex Inc., a Canadian corporation, is alleged based on its substantial contacts with Delaware, including through its control of Apotex Corp., sales of products in the state, and a history of consenting to jurisdiction by litigating in the district.
  • Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) to market a generic version of the drug KERENDIA® (finerenone) constitutes an act of infringement of a patent covering a method for preparing and purifying finerenone and the resulting crystalline form.
  • Technical Context: The dispute is in the field of pharmaceutical process chemistry, focusing on the industrial-scale synthesis and purification of an active pharmaceutical ingredient (API).
  • Key Procedural History: The patent-in-suit is a reissue of U.S. Patent No. 10,336,749. The litigation was triggered by Apotex’s Paragraph IV Notice Letter, which certified to the FDA that its proposed generic product would not infringe the patent-in-suit or that the patent is invalid. Bayer filed this complaint within the 45-day statutory window following receipt of the notice.

Case Timeline

Date Event
2015-08-21 RE’826 Patent Priority Date
2019-07-02 Original U.S. Patent No. 10,336,749 Issue Date
2021-07-09 FDA Approval of KERENDIA® (NDA No. 215341)
2024-02-06 U.S. Reissue Patent No. RE49,826 Issue Date
2025-09-05 Apotex sends Paragraph IV Notice Letter to Bayer
2025-10-15 Complaint Filing Date

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

U.S. Reissue Patent No. RE49,826 - "Method for the preparation of (4S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1-6-naphthyridine-3-carboxamide and the purification thereof for use as an active pharmaceutical ingredient"

The Invention Explained

  • Problem Addressed: The patent’s background section describes prior "research scale synthesis" methods for producing the finerenone compound as being unsuitable for large-scale, industrial manufacturing. These prior methods suffered from low overall yields, required very high dilution of reagents, and necessitated "many intermediate chromatographic purifications," which are described as technically laborious, costly, and solvent-intensive (RE’826 Patent, col. 2:45-58).
  • The Patented Solution: The patent discloses a novel and improved multi-step synthesis process that avoids the need for chromatographic purification of intermediates, resulting in a "very efficient synthesis" with high overall yield and purity suitable for industrial production (RE’826 Patent, col. 2:64-65; col. 4:1-6). The invention also includes the isolation of the final compound in a specific, stable crystalline form, designated "polymorph I," which is characterized by specific physical properties such as its X-ray diffractogram (RE’826 Patent, col. 13:57-65; col. 14:40-45).
  • Technical Importance: The development of a robust, scalable, and economically viable manufacturing process is a critical step in bringing a pharmaceutical product to market and ensuring a consistent supply of the active ingredient (RE’826 Patent, col. 2:59-63).

Key Claims at a Glance

  • The complaint alleges infringement of one or more claims of the RE’826 Patent, with Apotex's notice letter reportedly addressing claims 14-30 (Compl. ¶45, ¶55). Independent claim 27 is representative of the asserted product-by-process claims:
    • A compound of the formula (I) in crystalline form of polymorph I
    • prepared by a process comprising obtaining the compound of formula XIII
    • separating the compound of formula XIII by chiral separation to obtain the compound of formula I
    • dissolving the compound of formula I in an inert solvent
    • stirring at a temperature of 20° C.-120° C. and
    • isolating the compound of the formula (I) in crystalline form of polymorph I.

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Apotex's proposed generic finerenone drug product, for which it seeks FDA approval via ANDA No. 220684 ("Apotex's ANDA Product") (Compl. ¶1).

Functionality and Market Context

  • Apotex's ANDA Product is intended to be a generic equivalent of Bayer's KERENDIA®, a non-steroidal mineralocorticoid receptor antagonist (nsMRA) (Compl. ¶34). KERENDIA® is indicated to reduce the risk of kidney and cardiovascular problems in adults with chronic kidney disease associated with type 2 diabetes, among other uses (Compl. ¶34).
  • The infringement analysis will focus not on the therapeutic function of the drug, but on the confidential manufacturing process described in Apotex's ANDA used to produce the finerenone active pharmaceutical ingredient (API) and the resulting physical form of that API (Compl. ¶53-54).

IV. Analysis of Infringement Allegations

The complaint does not provide a detailed, element-by-element infringement analysis or a claim chart. Instead, it alleges on information and belief that Apotex's filing of its ANDA constitutes a technical act of infringement under 35 U.S.C. § 271(e)(2)(A) because the product Apotex intends to manufacture and sell upon approval is a "product claimed in the RE’826 Patent" (Compl. ¶53, ¶54). The core of the infringement theory rests on the assertion that Apotex’s confidential manufacturing process will result in the claimed crystalline form of finerenone and/or will practice the process steps recited in the patent's claims. No probative visual evidence provided in complaint.

  • Identified Points of Contention:
    • Scope Questions: A central question will be whether Apotex's confidential manufacturing process, as detailed in its ANDA, falls within the scope of the patent's claims. For example, does Apotex’s synthesis route involve the specific intermediate "compound of formula XIII," and does its purification process employ a "chiral separation" step on that intermediate, as required by claim 27 of the RE’826 Patent?
    • Technical Questions: The case will likely involve a detailed comparison of the physical characteristics of the finerenone API produced by Apotex’s process with the patent’s definition of "crystalline form of polymorph I." This raises the evidentiary question of whether Apotex's final product exhibits the specific X-ray diffraction peaks, IR spectrum, and melting point claimed in the patent.

V. Key Claim Terms for Construction

  • The Term: "crystalline form of polymorph I"

  • Context and Importance: The definition of this term is fundamental to the infringement analysis for claims directed to this specific solid-state form of finerenone. If Apotex's ANDA product contains a different polymorph or an amorphous version of the API, it may not infringe claims limited to "polymorph I."

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The complaint does not provide sufficient detail for analysis of arguments for a broader interpretation.
    • Evidence for a Narrower Interpretation: The patent provides a highly specific definition of polymorph I, explicitly characterizing it by its "x-ray diffractogram," which "exhibits peak maxima of the 2 theta angle at 8.5, 14.1, 17.2, 19.0, 20.5, 25.6, 26.5," its IR spectrum, and a defined melting point of 252° C. (RE’826 Patent, col. 14:40-45, col. 14:62-64, col. 14:65-col. 15:2). This detailed characterization provides strong intrinsic evidence for a narrow construction limited to a crystalline form exhibiting these precise physical properties.

  • The Term: "chiral separation"

  • Context and Importance: This term describes a key purification step in the claimed process for making the enantiomerically pure finerenone compound. Whether Apotex's method of separating stereoisomers meets this limitation will be a likely point of dispute. Practitioners may focus on this term because different separation technologies could exist, and the scope of this term could determine whether Apotex's process infringes.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The term itself is general and could be argued to encompass any technique used to separate enantiomers (chiral isomers) from a racemic mixture.
    • Evidence for a Narrower Interpretation: The specification describes a preferred embodiment of this step using a specific simulated moving bed (SMB) chromatography system on a "Chiralpak AS-V, 20 µm" stationary phase with a "methanol/acetonitrile 60:40" eluent (RE’826 Patent, col. 12:61-col. 13:13). A defendant could argue that the term should be construed more narrowly in light of these specific disclosures.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that upon FDA approval, Apotex will actively induce and contribute to infringement by marketing and selling its ANDA product (Compl. ¶56). The basis for this allegation is that Apotex intends for healthcare professionals and patients to use the infringing product according to its labeling, with knowledge of the patent (Compl. ¶64).
  • Willful Infringement: The complaint alleges that Apotex acted with "full knowledge of the RE’826 Patent and without a reasonable basis for believing that the manufacture, use or sale of its generic product would not infringe" (Compl. ¶57). This allegation is predicated on Apotex's pre-suit knowledge of the patent, as evidenced by its service of the Paragraph IV Notice Letter on Bayer (Compl. ¶42).

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

  • A core issue will be one of physical identity: Does the active pharmaceutical ingredient in Apotex’s proposed generic product exist in the specific "crystalline form of polymorph I" as defined by the patent’s detailed physical and spectral characteristics, or does it utilize a different, non-infringing solid-state form?
  • A second key question will be one of process correspondence: Will discovery reveal that Apotex’s confidential manufacturing process, as described in its ANDA, incorporates the key synthesis and purification steps recited in the patent’s product-by-process claims, particularly the "chiral separation" of the specified intermediate?