DCT
1:25-cv-03676
Melinta Subsidiary Corp v. Gland Pharma Ltd
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Melinta Therapeutics, LLC, Melinta Subsidiary Corp., and Rempex Pharmaceuticals, Inc. (Delaware)
- Defendant: Gland Pharma Limited (India)
- Plaintiff’s Counsel: Polsinelli PC
- Case Identification: 1:25-cv-03676, N.D. Ill., 04/04/2025
- Venue Allegations: Venue is alleged to be proper because the Defendant is a foreign corporation not residing in any U.S. judicial district and may therefore be sued in any district.
- Core Dispute: Plaintiff alleges that Defendant's submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Minocin® (minocycline) for injection infringes four patents related to stable tetracycline compositions.
- Technical Context: The technology involves pharmaceutical formulations of tetracycline antibiotics designed to improve stability and reduce hemolysis (destruction of red blood cells) upon intravenous injection, a common issue for this class of drugs.
- Key Procedural History: The complaint alleges that two of the patents-in-suit, U.S. Patent Nos. 9,278,105 and 9,084,802, were previously found valid and infringed after a bench trial in Melinta Therapeutics, LLC et al. v. Nexus Pharmaceuticals, Inc. in the same district. The complaint further alleges that Defendant's invalidity arguments are "nearly identical" to those rejected in the Nexus litigation, a fact that may influence the current proceedings.
Case Timeline
| Date | Event |
|---|---|
| 2010-05-12 | Earliest Priority Date for all Patents-in-Suit |
| 2015-07-21 | U.S. Patent No. 9,084,802 Issues |
| 2016-03-08 | U.S. Patent No. 9,278,105 Issues |
| 2024-04-02 | U.S. Patent No. 11,944,634 Issues |
| 2024-11-15 | District Court issues findings in Nexus Litigation |
| 2024-12-10 | U.S. Patent No. 12,161,656 Issues |
| 2025-02-21 | Defendant sends Paragraph IV Notice Letter |
| 2025-04-04 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,278,105 - "Tetracycline Compositions"
- Issued: March 8, 2016
The Invention Explained
- Problem Addressed: Tetracycline antibiotics, when prepared in aqueous solutions for injection, degrade rapidly and can cause hemolysis, which leads to venous phlebitis (irritation at the injection site) (’105 Patent, col. 1:40-50, col. 2:1-4). This limits their stability and can constrain the infusion volumes that patients can tolerate (’105 Patent, col. 2:1-4).
- The Patented Solution: The invention addresses this problem by formulating the tetracycline antibiotic with an excess of a divalent or trivalent cation, such as a magnesium cation (’105 Patent, Abstract). This formulation is claimed to significantly decrease the incidence of hemolysis and increase the stability of the aqueous solution, making it safer and more practical for intravenous administration (’105 Patent, col. 8:41-46).
- Technical Importance: This approach provided a method for creating more stable and safer injectable forms of widely used antibiotics, which is a significant practical advantage in a hospital setting where solutions may be prepared in advance of administration (Compl. ¶13-14).
Key Claims at a Glance
- The complaint does not identify specific claims but asserts infringement of one or more claims (Compl. ¶29). Independent method claim 1 is representative:
- A method of treating a bacterial infection in a subject comprising administering a therapeutically effective amount of a composition to a subject in need thereof via an intravenous route of administration,
- wherein the composition comprises an aqueous solution of a 7-dimethylamino-tetracycline antibiotic and a magnesium cation,
- wherein the molar ratio of magnesium cation to 7-dimethylamino-tetracycline antibiotic is greater than about 4:1, and
- wherein the solution does not comprise a pharmaceutically acceptable oil, has a pH greater than 4 and less than 7, and has an osmolality less than about 500 mOsm/kg.
- The complaint reserves the right to assert additional claims, which may include dependent claims (Compl. ¶29).
U.S. Patent No. 9,084,802 - "Tetracycline Compositions"
- Issued: July 21, 2015
The Invention Explained
- Problem Addressed: As with the related ’105 Patent, the technology targets the problems of chemical instability and injection-site hemolysis associated with aqueous formulations of tetracycline antibiotics (’802 Patent, col. 1:28-52).
- The Patented Solution: The patent describes methods of treating bacterial infections by intravenously administering compositions of minocycline (a type of tetracycline) formulated with a magnesium cation and a base, where the components are present in specific molar ratios and within specific pH and osmolality ranges (’802 Patent, Abstract; col. 2:5-10). This specific formulation is intended to provide improved stability and reduced hemolysis (’802 Patent, col. 8:41-46).
- Technical Importance: This solution offers a specific, defined formulation for minocycline that aims to overcome known administration challenges, thereby enhancing its therapeutic utility for intravenous use (Compl. ¶15).
Key Claims at a Glance
- The complaint does not identify specific claims but asserts infringement of one or more claims (Compl. ¶46). Independent method claim 1 is representative:
- A method of treating a bacterial infection in a subject, consisting of intravenously administering a therapeutically effective amount of a composition to a subject in need thereof,
- wherein the composition consists of an aqueous solution of minocycline or a salt thereof, a magnesium cation, and a base,
- wherein the molar ratio of magnesium cation to minocycline is from 5:1 to 10:1, and
- wherein the solution has a pH that is no less than 4 and no greater than 6, and has an osmolality less than about 500 mOsm/kg.
- The complaint reserves the right to assert additional claims, which may include dependent claims (Compl. ¶46).
U.S. Patent No. 11,944,634 - "Tetracycline Compositions"
Issued: April 2, 2024
Technology Synopsis: This patent, from the same family as the ’105 and ’802 patents, addresses the technical problems of chemical degradation and injection-site hemolysis in tetracycline antibiotics (’634 Patent, col. 1:36-67). The patented solution involves creating an intravenous formulation of minocycline with an excess of a divalent or trivalent cation (e.g., magnesium) at a specific molar ratio and pH to improve stability and reduce adverse effects (’634 Patent, col. 2:11-26).
Asserted Claims: The complaint asserts infringement of one or more claims, with independent claim 1 being representative (Compl. ¶63).
Accused Features: The accused features are those of the Gland ANDA Product, which the complaint alleges will contain the active ingredient minocycline and have the same formulation and properties as the reference drug Minocin® (Compl. ¶64).
U.S. Patent No. 12,161,656 - "Tetracycline Compositions"
Issued: December 10, 2024
Technology Synopsis: This patent, also from the same family, is directed to stable tetracycline compositions for intravenous use that mitigate the known problems of chemical instability and hemolysis (’656 Patent, col. 1:31-67). The invention consists essentially of an aqueous solution of minocycline and a magnesium cation at a specific molar ratio and pH range, which is claimed to reduce injection site hemolysis relative to formulations without magnesium (’656 Patent, col. 41:20-34, Claim 1).
Asserted Claims: The complaint asserts infringement of one or more claims, with independent claim 1 being representative (Compl. ¶76).
Accused Features: Infringement is alleged based on the formulation of the Gland ANDA Product, which is a generic version of Minocin® containing minocycline (Compl. ¶77).
III. The Accused Instrumentality
Product Identification
- The accused instrumentality is Defendant’s proposed generic 100 mg/vial minocycline hydrochloride for injection, identified as the "Gland ANDA Product" associated with ANDA No. 220209 (Compl. ¶1, ¶8).
Functionality and Market Context
- The Gland ANDA Product is a generic antibiotic intended for intravenous administration to treat bacterial infections (Compl. ¶13). As an ANDA product, it is designed to be a generic equivalent to the reference listed drug, Melinta's Minocin® (Compl. ¶1). The complaint alleges that pursuant to FDA regulations, the Gland ANDA Product "must contain the same inactive ingredients and in the same concentration as the reference listed drug" and will have the "same formulation and properties as Minocin®" (Compl. ¶30, ¶47, ¶64, ¶77). The complaint further alleges the product will be accompanied by a label that substantially copies the Minocin® label, thereby instructing physicians to use it in an infringing manner (Compl. ¶31, ¶48).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint. The infringement theory is based on the technical specifications of the Gland ANDA Product and its proposed labeling, rather than visual evidence of its use.
'978,105 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of treating a bacterial infection in a subject comprising administering a therapeutically effective amount of a composition...via an intravenous route... | The Gland ANDA Product is an injectable antibiotic whose label will instruct physicians to administer it intravenously for treating bacterial infections. | ¶31 | col. 42:1-5 |
| wherein the composition comprises an aqueous solution of a 7-dimethylamino-tetracycline antibiotic and a magnesium cation, | The Gland ANDA Product contains minocycline, which is a 7-dimethylamino-tetracycline antibiotic, and is alleged to have the same formulation as Minocin®, which includes a magnesium cation. | ¶30 | col. 42:6-9 |
| wherein the molar ratio of magnesium cation to 7-dimethylamino-tetracycline antibiotic is greater than about 4:1, | The Gland ANDA Product is alleged to have the same formulation as Minocin®, which meets this claimed molar ratio. Defendant's failure to assert non-infringement is presented as an admission of this element. | ¶30, ¶34 | col. 42:10-13 |
| wherein the solution does not comprise a pharmaceutically acceptable oil, has a pH greater than 4 and less than 7, and has an osmolality less than about 500 mOsm/kg. | The Gland ANDA Product is alleged to have the same formulation as Minocin®, which meets these physical and compositional parameters. | ¶30, ¶34 | col. 42:14-18 |
'9,084,802 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of treating a bacterial infection in a subject, consisting of intravenously administering a therapeutically effective amount of a composition... | The Gland ANDA Product's proposed label will instruct physicians on the intravenous administration of the composition for treating bacterial infections. | ¶48 | col. 41:1-5 |
| wherein the composition consists of an aqueous solution of minocycline or a salt thereof, a magnesium cation, and a base, | The Gland ANDA Product is alleged to have the same formulation as Minocin®, which consists of these required components. Defendant's failure to raise non-infringement is cited as an admission. | ¶47, ¶51 | col. 41:6-8 |
| wherein the molar ratio of magnesium cation to minocycline is from 5:1 to 10:1, | The Gland ANDA Product's formulation is alleged to match that of Minocin®, which falls within the claimed molar ratio range. | ¶47, ¶51 | col. 41:9-11 |
| wherein the solution has a pH that is no less than 4 and no greater than 6, and has an osmolality less than about 500 mOsm/kg. | The product's formulation is alleged to meet these specified pH and osmolality parameters. | ¶47, ¶51 | col. 41:12-15 |
Identified Points of Contention
- Scope Questions: The complaint's primary assertion is that Gland has effectively conceded infringement by not raising non-infringement defenses in its Paragraph IV notice letter (Compl. ¶34, ¶51). A central legal question will be the effect of this omission. For the ’802 Patent, the restrictive "consisting of" claim language raises the question of whether Gland's ANDA product contains any unrecited components that would place it outside the literal scope of the claims.
- Technical Questions: Since the Gland ANDA Product is not yet on the market, the infringement analysis relies on the assertion that its formulation and properties will be the "same" as Minocin® (Compl. ¶30, ¶47). A technical question for the court will be whether the evidence presented in Gland's ANDA filing confirms that its product formulation will, in fact, meet every claimed parameter, including the specific molar ratios, pH, and osmolality.
V. Key Claim Terms for Construction
The Term: "molar ratio...is greater than about 4:1" (’105 Patent, claim 1)
Context and Importance: This term defines the core of the patented solution: an excess of the magnesium cation relative to the antibiotic. The infringement analysis depends entirely on whether the Gland ANDA Product's formulation falls within this claimed ratio. Practitioners may focus on this term because any deviation in Gland's formulation could support a non-infringement argument.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The use of the word "about" suggests the ratio is not a rigid, absolute number and could encompass values slightly below 4:1. The specification discusses a range of molar ratios that provide the desired anti-hemolysis effect, potentially supporting a construction that is not strictly limited (’105 Patent, FIG. 3-5).
- Evidence for a Narrower Interpretation: The specification provides specific examples and data points, such as in Figure 4, showing a marked reduction in hemolysis at ratios of 5:1 and higher (’105 Patent, FIG. 4). A party could argue that "about 4:1" should be interpreted in light of these examples, limiting its scope to ratios that demonstrably achieve the patented benefit.
The Term: "consisting of" (’802 Patent, claim 1)
Context and Importance: This is a term of art in patent law that is presumptively closed, meaning the composition must contain only the listed ingredients (minocycline, magnesium cation, a base, and water for the solution) and no others. Practitioners may focus on this term because if the Gland ANDA Product contains any additional excipients or formulation agents, it would likely fall outside the literal scope of this claim.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party might argue that unlisted components that do not materially affect the basic and novel properties of the invention—here, the stability and reduced hemolysis from the specific minocycline-magnesium interaction—should not preclude infringement. This is, however, a high standard to meet.
- Evidence for a Narrower Interpretation: The choice of "consisting of" instead of the more open term "comprising" (used in the ’105 Patent) creates a strong presumption that the patentee intended to claim only the specific combination of listed elements. The prosecution history, if it shows a narrowing of the claim from "comprising" to "consisting of," would strongly support this narrow interpretation.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement on the basis that Defendant’s product label will instruct physicians and other healthcare providers to administer the Gland ANDA Product in a manner that directly infringes the method claims (Compl. ¶31, ¶48). Contributory infringement is alleged on the grounds that the product is especially made or adapted for an infringing use and is not suitable for a substantial non-infringing use (Compl. ¶37-38, ¶54-55).
- Willful Infringement: Willfulness is alleged based on Defendant’s purported "actual knowledge" of the patents-in-suit prior to its ANDA submission (Compl. ¶28, ¶45, ¶62, ¶75). The complaint emphasizes that Defendant's Paragraph IV notice was sent over three months after the court in the Nexus Litigation found related patents valid and infringed, suggesting Defendant proceeded despite a high likelihood of infringement (Compl. ¶24).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of validity and judicial precedent: to what extent will the prior judicial decision upholding the validity of the ’105 and ’802 patents against "nearly identical" invalidity arguments influence the court's analysis of both those patents and the newly issued patents from the same family?
- A central question of statutory infringement will be whether Gland's filing of an ANDA for a product with a formulation and proposed label that mirrors the patented methods constitutes an act of infringement under 35 U.S.C. § 271(e)(2), particularly given its alleged failure to assert non-infringement defenses in its Paragraph IV notice letter.
- A key evidentiary question will be one of claim scope: for the ’802 Patent, does the restrictive "consisting of" language create a viable non-infringement defense if Gland's proposed generic formulation contains any excipients not explicitly recited in the claim?