1:24-cv-00824
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: 1:24-cv-00824, D. Del., 07/16/2024
- Venue Allegations: Venue is alleged to be proper in the District of Delaware primarily because the Defendant is a limited liability company organized under the laws of Delaware.
- Core Dispute: Plaintiff alleges that Defendant’s Abbreviated New Drug Application (ANDA) to market a generic selenious acid injection constitutes an act of infringement of a patent on trace element compositions for parenteral nutrition.
- Technical Context: The technology concerns stable, injectable solutions of trace elements, such as selenium, used for parenteral nutrition in patients who cannot receive nourishment through their digestive tracts.
- Key Procedural History: Plaintiff’s Selenious Acid product is approved under New Drug Application (NDA) No. 209379. The patent-in-suit is listed in the FDA's "Orange Book" in connection with this NDA. Defendant filed an ANDA with a Paragraph IV certification, asserting non-infringement or invalidity of the patent, which serves as the statutory act of infringement triggering this lawsuit.
Case Timeline
| Date | Event |
|---|---|
| 2019-04-30 | Plaintiff's NDA No. 209379 approved by FDA |
| 2020-07-02 | '565 Patent Priority Date |
| 2024-06-04 | U.S. Patent No. 11,998,565 issued |
| 2024-06-11 | Defendant sent Paragraph IV Notice Letter |
| 2024-07-16 | Complaint filed |
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
The patent describes that trace elements added to parenteral nutrition (PN) solutions often result in admixtures with a short stability period of 24 to 48 hours. This necessitates frequent, costly, and time-consuming preparation of PN bags and prevents making them in larger, more efficient batches. (’565 Patent, col. 1:56 - col. 2:30).
The invention provides stable, injectable trace element compositions that can be added to parenteral nutrition, allowing the final admixture to be stored for a longer period. This reduces preparation time and costs, and improves the quality of life for patients and caregivers. (’565 Patent, Abstract; col. 2:31-44). The compositions are defined by specific concentrations of trace elements like zinc, copper, and selenium, and importantly, by low or non-existent levels of certain impurities. (’565 Patent, col. 3:1-12).
Developing stable, pre-formulated trace element additives simplifies the administration of parenteral nutrition, a critical therapy for patients with compromised digestive systems, by ensuring accurate dosing and reducing waste. (’565 Patent, col. 1:10-18).
Key Claims at a Glance
- The complaint generally alleges infringement of "one or more claims" of the ’565 Patent. Independent claim 15 is representative of the technology directed to the accused Selenious Acid product. (Compl. ¶16, ¶29).
- The essential elements of independent claim 15 are:
- 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
- iodine in an amount of 0.0001 µg to 0.2 µg
- per 1 mL of the injectable composition.
- The complaint reserves the right to assert other claims, which may include dependent claims that further narrow the composition. (Compl. ¶29, ¶30).
III. The Accused Instrumentality
Product Identification
The accused instrumentality is the generic drug product described in Defendant’s ANDA No. 218779, identified as "Selenious Acid Injection, USP (eq. 600 mcg Selenium/10 mL (eq 60 mcg Selenium/mL))" ("the ANDA Product"). (Compl. ¶1, ¶24).
Functionality and Market Context
The ANDA Product is alleged to be a generic version of Plaintiff's Selenious Acid product, intended for use as a source of selenium in parenteral nutrition. (Compl. ¶23). The complaint alleges that the ANDA Product contains the same or equivalent active ingredients in the same or equivalent amounts and will possess the same or equivalent chemical and therapeutic properties as Plaintiff's approved drug. (Compl. ¶25, ¶26). By filing an ANDA, Defendant seeks to market this product as a lower-cost, bioequivalent alternative to Plaintiff’s branded product before the expiration of the ’565 Patent. (Compl. ¶1). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint does not include an explicit claim chart. The infringement allegations are based on the premise that the ANDA Product is a generic copy of Plaintiff's patented product. (Compl. ¶23, ¶26). The following table summarizes the infringement theory for representative claim 15 based on the allegations in the complaint.
'565 Patent Infringement Allegations
| Claim Element (from Independent Claim 15) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| An injectable composition comprising water... | The ANDA Product is an aqueous "Selenious Acid Injection, USP." | ¶24 | col. 11:26-29 |
| 6 µg or 60 µg of selenium... per 1 mL of the injectable composition | The ANDA Product is formulated to contain "60 mcg Selenium/mL," which is equivalent to 60 µg/mL. | ¶24 | col. 11:20-29 |
| no chromium or chromium in an amount not to exceed 1 µg... per 1 mL | The complaint alleges the ANDA Product features the "same or equivalent chemical and therapeutic properties" as Plaintiff's product, which is covered by the claims, implying it meets this purity limit. | ¶26 | col. 17:1-3 |
| no aluminum or aluminum in an amount not to exceed 6 µg... per 1 mL | The allegation that the ANDA Product is a generic copy implies that it meets the claimed limitation on aluminum content. | ¶26 | col. 18:15-25 |
| no iron or iron in an amount up to 10 µg... per 1 mL | The allegation that the ANDA Product has the "same or equivalent ingredients" implies it meets the claimed limitation on iron content. | ¶26 | col. 16:12-25 |
| iodine in an amount of 0.0001 µg to 0.2 µg... per 1 mL | The general allegation of equivalence implies the ANDA Product falls within the claimed range for iodine content. | ¶26 | col. 17:5-9 |
- Identified Points of Contention:
- Technical Questions: The central dispute will likely be factual and evidentiary. A key question is whether Fresenius’s ANDA Product, as described in its confidential application to the FDA, literally meets every positive and negative limitation of the asserted claims. The analysis will depend on the precise quantities of not only selenium but also the specified impurities (chromium, aluminum, iron, iodine) present in the accused formulation.
V. Key Claim Terms for Construction
The complaint does not provide sufficient detail to identify terms that are currently in dispute. However, the following terms are central to the infringement analysis.
The Term: "no chromium or chromium in an amount not to exceed 1 µg"
- Context and Importance: This negative limitation is a critical feature that distinguishes the claimed invention. Infringement will depend on a factual analysis of the ANDA product's composition. Practitioners may focus on this term because it creates a clear, testable threshold for infringement that can be resolved through chemical analysis of the formulation specified in the ANDA.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The complaint does not present evidence for an interpretation other than the plain meaning.
- Evidence for a Narrower (i.e., strict) Interpretation: The patent specification repeatedly discusses the goal of creating purer, more customizable formulations, and Table 4 provides specific limits for numerous elemental impurities, underscoring the importance of purity to the invention. (’565 Patent, col. 2:49-53; Table 4, col. 17). This context supports a strict, literal reading of the limitation.
The Term: "no aluminum or aluminum in an amount not to exceed 6 µg"
- Context and Importance: This limitation is also central to the infringement question. The patent specification explicitly addresses the problem of aluminum contamination from containers, especially its danger to patients with impaired kidney function, such as preterm infants. (’565 Patent, col. 24:1-24).
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The complaint does not present evidence for an interpretation other than the plain meaning.
- Evidence for a Narrower (i.e., strict) Interpretation: The patent’s detailed discussion of aluminum toxicity and the need to minimize patient exposure provides strong intrinsic support for construing this limitation strictly according to its plain language. (’565 Patent, col. 18:15-25, col. 24:1-24).
VI. Other Allegations
- Indirect Infringement: The complaint alleges that upon approval, Defendant will induce infringement by providing a package insert that instructs medical professionals on how to use the ANDA Product in an infringing manner. (Compl. ¶29, ¶30). It also alleges contributory infringement, stating the product is especially made for infringing use and is not suitable for substantial non-infringing use. (Compl. ¶30).
- Willful Infringement: The complaint does not use the term "willful," but it does allege the case is "exceptional" and seeks attorneys' fees. (Compl. ¶33). The basis for this allegation appears to be that Defendant had knowledge of the ’565 Patent at least as of the date it submitted its ANDA with the Paragraph IV certification. (Compl. ¶32).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of factual composition: Does the precise formulation of Fresenius’s ANDA product, as specified in its confidential FDA filing, meet every limitation of the asserted claims, particularly the stringent negative limitations on elemental impurities like chromium and aluminum?
- A key evidentiary question will be one of chemical identity: The case will turn on whether the evidence contained within the ANDA demonstrates that Fresenius's product is chemically identical to the claimed composition, not just therapeutically equivalent. The dispute will center on a direct comparison between the patent’s specific purity requirements and the ANDA’s product specification.