American Regent Inc v. Fresenius Kabi USA LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: American Regent, Inc. (New York)
  • Defendant: Fresenius Kabi USA, LLC (Delaware)
  • Plaintiff’s Counsel: Gibbons P.C.; Sterne, Kessler, Goldstein & Fox P.L.L.C.
• Case Identification: 2:24-cv-07801, D.N.J., 07/16/2024
• Venue Allegations: Plaintiff alleges venue is proper in the District of New Jersey because Defendant Fresenius Kabi USA, LLC has systematic and continuous business contacts with the state, is registered as a business and manufacturer in New Jersey, derives substantial revenue from the state, and plans to sell the accused product in the judicial district.
• Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (ANDA) for a generic version of Plaintiff's Selenious Acid injection product constitutes an act of infringement of a patent covering trace element compositions.
• Technical Context: The technology concerns stable, injectable trace element compositions for use in parenteral nutrition, which is administered intravenously to patients who cannot receive nourishment through their digestive tract.
• Key Procedural History: The lawsuit was initiated under the Hatch-Waxman Act following a notice letter from Fresenius, dated June 11, 2024, informing American Regent of its ANDA filing containing a Paragraph IV certification. The patent-in-suit is listed in the U.S. Food and Drug Administration's "Orange Book" as covering American Regent's Selenious Acid products.

Case Timeline

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

U.S. Patent No. 11,998,565 - Trace element compositions, methods of making and use

The Invention Explained

• Problem Addressed: The patent describes a problem in the field of parenteral nutrition (PN) where admixing trace elements into a PN solution leads to a short stability period of 24 to 48 hours. This short window results in wasted product, increased costs, and logistical burdens for patients and caregivers who must frequently prepare or obtain new admixtures (’565 Patent, col. 1:5-10, col. 2:5-16).
• The Patented Solution: The invention provides stable, injectable compositions containing specific trace elements that, when added to parenteral nutrition, allow the final admixture to remain stable for a longer period of time. The patent describes specific formulations, including some with lower concentrations of certain elements compared to then-currently available products, which can be customized for patient needs (’565 Patent, Abstract; col. 2:40-54).
• Technical Importance: This technology aims to reduce waste and cost associated with parenteral nutrition and improve the quality of life for patients by enabling the preparation of stable PN solutions in batches, reducing the need for daily admixing (’565 Patent, col. 2:31-39).

Key Claims at a Glance

• The complaint asserts infringement of "one or more claims" of the ’565 patent (Compl. ¶28). Independent claim 1 is representative:
• An injectable composition comprising:
  • water,
  • 6 µg or 60 µg of selenium,
  • no chromium or chromium in an amount not to exceed 1 µg,
  • no aluminum or aluminum in an amount not to exceed 6 µg,
  • no iron or iron in an amount up to 10 µg, and
  • fluoride in an amount of 0.0001 µg to 2.7 µg per 1 mL of the injectable composition.
• The complaint reserves the right to assert other claims, including dependent claims (Compl. ¶28).

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Defendant's proposed generic "Selenious Acid Injection, USP" product, which is the subject of Abbreviated New Drug Application (ANDA) No. 218779 submitted to the FDA (Compl. ¶1, ¶23).

Functionality and Market Context

• The complaint alleges the ANDA Product is a generic version of Plaintiff's Selenious Acid products and contains the same or equivalent active ingredients in the same or equivalent amounts (Compl. ¶22). Specifically, the product is identified as containing a concentration equivalent to 60 mcg of selenium per mL (Compl. ¶23).
• The ANDA product is intended to be used as a supplement for parenteral nutrition and, as a generic, would compete with Plaintiff's branded product upon FDA approval (Compl. ¶25, ¶28).
• No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

’565 Patent Infringement Allegations

• Identified Points of Contention:
  • Evidentiary Questions: The complaint's allegations are based on "information and belief" and the notice letter. A primary point of contention will be factual and evidentiary: does the formulation described in Fresenius's confidential ANDA filing actually meet the negative limitations of the asserted claims? The infringement analysis will depend entirely on the specified levels of chromium, aluminum, iron, and fluoride in the proposed generic product, which are not detailed in the complaint.
  • Scope Questions: The case raises the question of whether Fresenius's formulation, which may contain various excipients and manufacturing impurities, falls within the scope of claims defined by what they both contain (selenium) and what they must not contain in excess (chromium, aluminum, iron, etc.).

V. Key Claim Terms for Construction

• The Term: "comprising"
• Context and Importance: As a transitional phrase in Claim 1, the definition of "comprising" is critical for determining the scope of the claim. Its interpretation dictates whether the presence of additional, unrecited elements in Fresenius's ANDA Product would allow it to fall outside the claim's boundaries.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: Patent law has a well-established, open-ended definition for "comprising," meaning the claimed invention can include unrecited elements and still infringe. The patent's consistent use of "comprising" in its independent claims (e.g., Claims 1, 15) may support the application of this standard, broad interpretation.
  • Evidence for a Narrower Interpretation: A party seeking a narrower scope may argue that the nature of the invention—a precise chemical formulation where impurities are critical—warrants a more restrictive reading. The patent also uses the more limiting phrase "consists essentially of" in the specification, which could be used to argue that the invention is limited to the recited elements and those that do not materially affect its basic and novel characteristics, such as stability (’565 Patent, col. 4:8-9).

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement, stating that Fresenius's proposed package insert for the ANDA Product will instruct and encourage medical professionals to administer the product in a manner that infringes the ’565 Patent (Compl. ¶28). It further alleges contributory infringement, claiming the ANDA Product is especially made for an infringing use and is not suitable for substantial non-infringing use (Compl. ¶29).
• Willful Infringement: The complaint alleges that Fresenius has known of the ’565 Patent since at least the date it submitted its ANDA with a Paragraph IV certification (Compl. ¶31). Plaintiff further asserts that the case is "exceptional" and seeks an award of attorneys' fees, which is consistent with an allegation of willful or egregious infringement conduct (Compl. ¶32).

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

• A central issue will be one of factual proof: Does the precise chemical composition of Fresenius's proposed generic product, as detailed in its confidential ANDA, meet every positive and negative limitation of the asserted claims? The case will likely hinge on a direct comparison of the ANDA formulation data against the patent’s specific concentration ranges for both the required selenium and the restricted impurities.
• A second core issue will relate to patent validity: Fresenius's Paragraph IV certification alleges that the patent is either not infringed or is invalid. A key question for the court will be whether the specific formulation of Claim 1—defined by what it includes, what it excludes, and in what precise amounts—was non-obvious in light of prior art parenteral nutrition solutions and trace element supplements.