DCT
1:24-cv-00846
Nivagen Pharma Inc v. Amneal Pharma Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Nivagen Pharmaceuticals, Inc. (Delaware)
- Defendant: Amneal Pharmaceuticals, Inc. and Amneal Pharmaceuticals LLC (Delaware)
- Plaintiff’s Counsel: Potter Anderson & Corroon LLP
- Case Identification: 1:24-cv-00846, D. Del., 07/19/2024
- Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because both Defendants are incorporated and reside in Delaware.
- Core Dispute: Plaintiff seeks a declaratory judgment that Defendant’s imminent commercial launch of a ready-to-use potassium phosphate intravenous solution will infringe two patents related to stable, low-aluminum pharmaceutical formulations.
- Technical Context: The technology concerns ready-to-use intravenous solutions for phosphorus replacement therapy, which are intended to improve patient safety by eliminating the need for bedside dilution of concentrated drugs, a process prone to calculation errors and contamination.
- Key Procedural History: This action was filed as a complaint for declaratory judgment, indicating that the accused product has not yet been launched but that Plaintiff believes its launch and subsequent infringement are imminent based on Defendant's public statements. The complaint notes a Certificate of Correction was issued for U.S. Patent No. 11,925,661, which modified a pH range in the claims.
Case Timeline
| Date | Event |
|---|---|
| 2020-10-12 | Earliest Priority Date for ’291 and ’661 Patents |
| 2023-11-14 | U.S. Patent No. 11,813,291 Issues |
| 2024-03-12 | U.S. Patent No. 11,925,661 Issues |
| 2024-06-05 | Defendant's investor presentation announcing expected 2024 product launch |
| 2024-07-19 | Complaint for Declaratory Judgment Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,813,291 - Ready-To-Use Potassium Phosphates In Sodium Chloride Solutions
- Issued: November 14, 2023
The Invention Explained
- Problem Addressed: The patent's background describes challenges with existing potassium phosphate products used for intravenous phosphorus replacement therapy. These products are typically supplied as concentrates that require aseptic compounding before administration, creating risks of miscalculation, contamination, and adverse patient reactions. The patent also notes issues with chemical stability (crystallization) and aluminum toxicity, particularly in renally impaired patients. (’291 Patent, col. 2:9-53).
- The Patented Solution: The invention provides a sterile, "ready-to-use" (RTU) potassium phosphate solution packaged in a flexible container. This premixed formulation contains specific concentrations of potassium phosphates and sodium chloride (as a tonicity agent), has a controlled pH, and features an ultra-low concentration of aluminum. This design allows for direct administration to a patient without the need for bedside dilution or complex calculations. (’291 Patent, Abstract; col. 3:12-25).
- Technical Importance: This approach seeks to improve patient safety by providing a standardized, premixed, and stable formulation that mitigates the risks of contamination and dosage errors inherent in the clinical practice of diluting concentrated drugs. (’291 Patent, col. 2:15-22).
Key Claims at a Glance
- The complaint asserts infringement of at least independent claim 11 (Compl. ¶69). The complaint also notes that claims 1 and 17 are independent (Compl. ¶18).
- Independent Claim 11 Elements:
- A sterile ready-to-use premixed pharmaceutical product stored in a flexible polymeric container,
- wherein the pharmaceutical product comprises a potassium phosphates in an aqueous sodium chloride solution containing
- (a) less than 50 mcg/L aluminum,
- (b) about 15 mmol/100 ml phosphorus, and
- (c) about 22 mEq/100 mL potassium.
U.S. Patent No. 11,925,661 - Ready-To-Use Potassium Phosphates In Sodium Chloride Solutions
- Issued: March 12, 2024
The Invention Explained
- Problem Addressed: Similar to its parent, the ’661 Patent addresses the safety and stability risks associated with concentrated potassium phosphate solutions that require dilution prior to intravenous administration, including the potential for contamination, dosage errors, and aluminum toxicity. (’661 Patent, col. 2:10-51).
- The Patented Solution: The patent claims a sterile, ready-to-use aqueous potassium solution that contains potassium phosphates, sodium chloride, and has specifically defined ranges for phosphorus concentration, aluminum content, and pH. A Certificate of Correction modified the pH range in claim 1 from "between 2 and 6" to "between 6.2 and 6.8," a range suitable for direct injection. The solution is designed to be administered directly from its container. (’661 Patent, Abstract; col. 3:20-30; Certificate of Correction).
- Technical Importance: The invention provides a safer and more convenient therapeutic option for treating hypophosphatemia by offering a premixed, stable formulation that reduces the potential for human error in a clinical setting. (’661 Patent, col. 2:15-22).
Key Claims at a Glance
- The complaint asserts infringement of at least independent claims 1, 11, and 17 (Compl. ¶81).
- Independent Claim 1 Elements (as corrected):
- A sterile ready-to-use aqueous potassium solution,
- comprising potassium phosphates and sodium chloride,
- wherein the solution comprises between 1.5 mmol/100 mL and 15 mmol/100 ml phosphorous and equal or less than 50 mcg/L aluminum,
- and wherein the solution has a pH of between 6.2 and 6.8.
III. The Accused Instrumentality
Product Identification
- Defendant's "Potassium phosphate (IV bag)" product (the "Product") (Compl. ¶25, Ex. C).
Functionality and Market Context
- The Product is described as an injectable, "Ready-To-Use (RTU)" drug product intended for launch in 2024 following expected FDA approval (Compl. ¶25, 26, 31). The complaint alleges, upon information and belief, that the Product will be a sterile, premixed solution stored in a flexible IV bag and will contain potassium phosphates, sodium chloride, phosphorus, and aluminum in amounts that fall within the scope of the asserted patent claims (Compl. ¶37-41). Defendant has publicly identified the Product as a "potential high-value opportunity" and a "growth catalyst" (Compl. ¶24, 28). A screenshot from Defendant's investor presentation shows the "Potassium phosphate (IV bag)" listed as an expected 2024 launch under the "Injectables" category (Compl. Ex. C at 19).
IV. Analysis of Infringement Allegations
’291 Patent Infringement Allegations
| Claim Element (from Independent Claim 11) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A sterile ready-to-use premixed pharmaceutical product stored in a flexible polymeric container... | The Product is described as a "Ready-To-Use (RTU)" injectable that will be sold in an "IV bag," which is a flexible polymeric container, and is alleged to be sterile. | ¶26, ¶32, ¶37, ¶39 | col. 3:59-62 |
| wherein the pharmaceutical product comprises a potassium phosphates in an aqueous sodium chloride solution... | The Product is identified as a "potassium phosphate injectable drug product" and is alleged to contain sodium chloride to form a saline solution. | ¶23, ¶38 | col. 3:26-30 |
| containing (a) less than 50 mcg/L aluminum, | Based on FDA regulations for large volume parenteral drugs, the complaint alleges the Product will contain less than 50 mcg/l of aluminum. | ¶34-36 | col. 3:64-65 |
| (b) about 15 mmol/100 ml phosphorus, and | The complaint alleges, upon information and belief, that the Product will contain the claimed amount of phosphorus. | ¶40 | col. 3:65-66 |
| (c) about 22 mEq/100 mL potassium. | The complaint alleges, upon information and belief, that the Product will contain the claimed amount of potassium. | ¶40 | col. 4:1-2 |
’661 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A sterile ready-to-use aqueous potassium solution, | The Product is described as a "Ready-To-Use (RTU)" injectable that will be sterile. | ¶26, ¶32, ¶37 | col. 3:20-21 |
| comprising potassium phosphates and sodium chloride, | The Product is identified as a potassium phosphate product and is alleged to contain sodium chloride. | ¶23, ¶38 | col. 3:21-22 |
| wherein the solution comprises between 1.5 mmol/100 mL and 15 mmol/100 ml phosphorous and equal or less than 50 mcg/L aluminum, | The complaint alleges the Product will meet these concentration limitations, citing FDA regulations regarding aluminum levels. | ¶36, ¶41 | col. 3:22-25 |
| and wherein the solution has a pH of between 6.2 and 6.8. | The complaint alleges on information and belief that the Product will have a pH within the claimed ranges. | ¶38, ¶41 | col. 3:44-45 |
Identified Points of Contention
- Factual Questions: Because this is a declaratory judgment action concerning a product not yet on the market, the central dispute will be factual. The complaint's allegations regarding the precise chemical composition of the accused Product (e.g., concentrations of phosphorus, potassium, aluminum, and pH) are made "upon information and belief." The key question will be whether the final, FDA-approved product formulation actually possesses the characteristics required by the claims. The complaint cites a slide defining "RTU" as "Ready-to-use" to support its characterization of the accused product (Compl. ¶27).
- Scope Questions: The term "about" in claim 11 of the ’291 Patent modifies the required concentrations of phosphorus and potassium. The scope of this term may become a central point of claim construction, as it will determine how much, if any, deviation from the specified values is permissible for a finding of infringement.
V. Key Claim Terms for Construction
The Term: "about"
- Context and Importance: This term appears in claim 11 of the ’291 Patent, qualifying the required concentrations of phosphorus ("about 15 mmol/100 ml") and potassium ("about 22 mEq/100 mL"). The construction of "about" will be critical to determining the literal scope of the claim. Practitioners may focus on this term because even a small variance in the accused Product's final formulation could place it outside a narrow construction of the claim.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The term "about" is used numerous times throughout the specification when describing concentrations, suggesting an intent to encompass normal manufacturing tolerances and minor variations rather than requiring exact numerical precision (’291 Patent, col. 3:4-10).
- Evidence for a Narrower Interpretation: The patent provides specific target formulations and detailed stability data for those precise concentrations (’291 Patent, e.g., Table 3, col. 10:11-30). A party could argue that these specific examples define the reasonable scope of "about" and that the claimed values are critical to achieving the invention's stated stability and safety benefits.
The Term: "ready-to-use"
- Context and Importance: This term defines the fundamental nature of the claimed invention in both patents. The dispute will center on whether the accused Product, as sold, meets this definition. If the Product requires any pre-administration steps beyond connecting it to an IV line, its "ready-to-use" status could be contested.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification states that a "ready-to-use" solution "can be directly administered to a patient without prior need for dilution or other adjustment such as addition of saline or other tonicity agent" (’291 Patent, col. 5:40-44).
- Evidence for a Narrower Interpretation: The patent also states that an RTU solution can be delivered "without additional manipulation of the solution in the storage container" (’291 Patent, col. 5:46-49). This language could be used to argue that even minor required manipulations, such as activating a dual-chamber bag, might render a product not "ready-to-use" as contemplated by the patent.
VI. Other Allegations
Indirect Infringement
- The complaint alleges that Defendants will induce infringement by marketing the Product to healthcare practitioners, advertising its availability, and providing instructions (e.g., via product labels and manuals) that will encourage its administration in an infringing manner for phosphorus replacement therapy (Compl. ¶70, 82).
Willful Infringement
- The complaint alleges willfulness based on pre-suit knowledge. It asserts that Defendants monitor patent applications in this technology space and therefore had actual notice of the asserted patents upon their issuance. It alleges that Defendants' continued efforts to obtain FDA approval and commercialize the Product despite this knowledge demonstrate reckless disregard for Plaintiff's patent rights (Compl. ¶72-74, 84-86).
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary issue will be one of evidentiary proof: what will be the final, FDA-approved chemical composition of Amneal's product? As the complaint is for declaratory judgment, the case hinges on whether the yet-to-be-launched product's characteristics—specifically its concentrations of phosphorus, potassium, aluminum, and its pH—will in fact fall within the numerical limits of the asserted claims.
- The case will also likely involve a core claim construction dispute over the scope of the term "about" in the ’291 patent. The court's interpretation of this term will define the boundary for infringement and could be dispositive if the accused product's formulation is close to, but not identical to, the recited values.