Bayer Healthcare Pharma Inc v. Aurobindo Pharma Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Bayer HealthCare Pharmaceuticals Inc. (Delaware); Bayer Pharma Aktiengesellschaft (Germany); Bayer Aktiengesellschaft (Germany)
  • Defendant: Aurobindo Pharma Ltd. (India); Aurobindo Pharma U.S.A., Inc. (Delaware)
  • Plaintiff’s Counsel: McCarter & English, LLP; Arnold & Porter Kaye Scholer LLP
• Case Identification: Bayer HealthCare Pharmaceuticals Inc. v. Aurobindo Pharma Ltd., 1:25-cv-01246, D. Del., 10/09/2025
• Venue Allegations: Venue is alleged to be proper for Defendant Aurobindo Pharma U.S.A., Inc. as it is a Delaware corporation. Venue for Defendant Aurobindo Pharma Ltd. is based on its status as a foreign corporation allegedly subject to personal jurisdiction in the district through its U.S. subsidiary and other contacts.
• Core Dispute: Plaintiff alleges that Defendant’s Abbreviated New Drug Application (ANDA) to market a generic version of the drug KERENDIA® (finerenone) constitutes an act of infringement of a patent claiming a specific crystalline form of the finerenone active pharmaceutical ingredient.
• Technical Context: The technology relates to pharmaceutical chemistry, specifically the solid-state form of a non-steroidal mineralocorticoid receptor antagonist used for treating chronic kidney disease and certain types of heart failure.
• Key Procedural History: The litigation was triggered by Defendant's submission of ANDA No. 220696 to the U.S. Food and Drug Administration (FDA) containing a Paragraph IV certification, asserting that the patent-in-suit is invalid and/or will not be infringed by its proposed generic product. The patent-in-suit is a reissue of U.S. Patent No. 10,336,749.

Case Timeline

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"

• Patent Identification: 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," issued February 6, 2024.

The Invention Explained

• Problem Addressed: The patent's background section notes that prior research-scale synthesis methods for the active ingredient finerenone were "unsuitable for a further large-scale process" because they involved many steps at high dilution, required "very high excesses of reagents," and relied on "laborious" chromatographic purifications, resulting in low overall yield and high cost (’826 Patent, col. 5:48-59).
• The Patented Solution: The patent describes an "industrially practicable synthesis" designed to produce the finerenone compound in high yield and purity, meeting regulatory requirements for clinical trials and commercial production (’826 Patent, col. 5:61-64). A key part of the solution is a final crystallization process that reproducibly yields a single, defined crystalline form, designated "polymorph I," which has a specific melting point and is described as having "very good stability properties" (’826 Patent, col. 13:56-65; col. 15:26-31).
• Technical Importance: The development of a stable, reproducible crystalline polymorph with an efficient, scalable manufacturing process is a critical step in transforming a laboratory chemical into a viable commercial pharmaceutical product.

Key Claims at a Glance

• The complaint does not identify specific asserted claims, but Aurobindo's Paragraph IV letter reportedly challenged claims 14-30 (Compl. ¶43). Claim 14 is the first and broadest independent claim of the reissued patent.
• Independent Claim 14:
  • A compound of the formula (I) [finerenone]
  • in crystalline form of polymorph I
  • wherein the x-ray diffractogram of the compound exhibits peak maxima of the 2 theta angle at 8.5, 14.1, and 19.0.
• The complaint does not explicitly reserve the right to assert dependent claims, but alleges infringement of "one or more claims" (Compl. ¶54).

III. The Accused Instrumentality

Product Identification

• The accused instrumentality is the generic finerenone drug product described in Aurobindo's ANDA No. 220696, intended for marketing as 10 mg and 20 mg tablets (Compl. ¶1, ¶27).

Functionality and Market Context

• The product is a generic version of Bayer's KERENDIA®, which is a non-steroidal mineralocorticoid receptor antagonist (nsMRA) (Compl. ¶1, ¶32). It is indicated to reduce the risk of kidney function decline, kidney failure, cardiovascular death, and hospitalization for heart failure in certain patient populations (Compl. ¶32). The complaint alleges that Aurobindo seeks to market its generic version before the expiration of the ’826 Patent (Compl. ¶1).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not contain a claim chart or provide specific factual allegations mapping elements of the accused product to the patent claims. The infringement theory is based on the act of filing the ANDA, which under 35 U.S.C. § 271(e)(2) is a statutory act of infringement if the proposed product would infringe the patent upon commercialization (Compl. ¶51). The core allegation is that Aurobindo's ANDA product, if approved and marketed, will be or will contain the specific crystalline form of finerenone—polymorph I—claimed in the ’826 Patent (Compl. ¶52-¶53).

• Identified Points of Contention:
  • Evidentiary Question: The central dispute will likely be factual and evidentiary. The primary question is whether the finerenone Active Pharmaceutical Ingredient (API) in Aurobindo's ANDA product meets the specific physical characterization criteria for "polymorph I" as defined by the patent's claims. This will likely require laboratory analysis of Aurobindo's product samples via techniques like X-ray powder diffraction (XRPD), infrared (IR) spectroscopy, and differential scanning calorimetry (DSC).
  • Scope Questions: A potential point of contention may arise over the scope of the claim limitations. For example, the parties may dispute how closely the peaks in the accused product's X-ray diffractogram must match the specific "2 theta angle" values recited in claim 14 (e.g., 8.5, 14.1, 19.0) to be considered infringing.

V. Key Claim Terms for Construction

• The Term: "crystalline form of polymorph I"
• Context and Importance: This term is the central limitation of the asserted claims. The entire infringement case may turn on whether Aurobindo's API falls within the definition of this specific polymorph. The patent defines this term not by a simple phrase, but through a collection of specific, measurable physical properties recited in the claims.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent does not appear to provide explicit language supporting a broad interpretation. A plaintiff might argue that the term should be understood to encompass minor, immaterial variations in measured values (e.g., peak positions in an X-ray diffractogram) that are within the bounds of standard experimental error for the analytical techniques used.
  • Evidence for a Narrower Interpretation: The patent provides highly specific data to define polymorph I. Claim 14 requires XRPD peaks at "8.5, 14.1, and 19.0," while dependent claim 15 adds peaks at "17.2, 20.5, 25.6, and 26.5" (’826 Patent, col. 56:65-57:4). The specification further states that this polymorph has a "defined melting point of 252° C" (’826 Patent, col. 13:63-65). A defendant may argue that these precise numerical values strictly define the polymorph, and any API that does not exhibit these exact characteristics is non-infringing.

VI. Other Allegations

• Indirect Infringement: The complaint alleges that upon FDA approval, Aurobindo will induce and contribute to infringement by health care professionals and patients who will use the generic product in accordance with its labeling (Compl. ¶61-¶62).
• Willful Infringement: The complaint alleges that Aurobindo acted with "full knowledge of the RE'826 Patent" because it submitted a Paragraph IV certification to the FDA regarding the patent (Compl. ¶55). Bayer also asserts that the case is "exceptional" and seeks attorneys' fees (Compl. ¶65).

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

The resolution of this case will likely depend on the answers to two central questions:

• A primary question will be one of evidentiary proof: does the active pharmaceutical ingredient in Aurobindo's proposed generic product, when subjected to standard analytical testing, exhibit the specific physical and chemical properties—particularly the X-ray diffraction peaks—that define the patented "crystalline form of polymorph I"?
• A secondary, but potentially dispositive, issue will be one of claim construction: how should the court interpret the precise numerical values recited in the claims (e.g., "2 theta angle at 8.5")? The case may turn on whether these values require exact identity or if they encompass a range of values reflecting normal experimental variability.