DCT

2:20-cv-02576

IN RE SUGAMMADEX

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:20-cv-02576, D.N.J., 03/10/2020
  • Venue Allegations: Venue is alleged to be proper in the District of New Jersey because Defendant Aurobindo USA has a regular and established place of business in the state, and Defendant Aurobindo Pharma Limited is a foreign entity that may be sued in any judicial district.
  • Core Dispute: This is a patent infringement action under the Hatch-Waxman Act, in which Plaintiff alleges that Defendant's Abbreviated New Drug Application (ANDA) to market a generic version of the anesthetic reversal agent Bridion® (sugammadex) infringes a patent covering the drug's active ingredient.
  • Technical Context: The technology concerns modified cyclodextrins designed to act as reversal agents for neuromuscular blocking drugs used during surgery, offering a more targeted mechanism with potentially fewer side effects than traditional agents.
  • Key Procedural History: The patent-in-suit, RE44,733, is a reissue of U.S. Patent No. 6,670,340. The complaint notes that the USPTO issued a Notice of Final Determination finding the patent eligible for a five-year Patent Term Extension (PTE), which would extend its expiration to January 27, 2026. This lawsuit was triggered by Defendant's submission of an ANDA with a Paragraph IV certification, asserting that the patent is invalid, unenforceable, or will not be infringed by the proposed generic product.

Case Timeline

Date Event
1999-11-29 Earliest Priority Date for RE44,733 Patent
2003-12-30 Issue Date of Original U.S. Patent No. 6,670,340
2014-01-28 Issue Date of Reissued U.S. Patent No. RE44,733
2015-12-15 FDA Approval of Bridion® (sugammadex) Injection (NDA No. 022225)
2020-02-04 USPTO Notice of Final Determination on Patent Term Extension for '733 Patent
2020-02-07 Date of Aurobindo's ANDA Notice Letter to Merck
2020-03-10 Complaint Filing Date

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

U.S. Reissued Patent No. RE44,733 - "6-Mercapto-Cyclodextrin Derivatives: Reversal Agents For Drug-Induced Neuromuscular Block"

  • Patent Identification: U.S. Reissued Patent No. RE44,733, “6-Mercapto-Cyclodextrin Derivatives: Reversal Agents For Drug-Induced Neuromuscular Block,” issued January 28, 2014.

The Invention Explained

  • Problem Addressed: The patent describes the problem of reversing neuromuscular blockade induced by drugs (NMBAs) during anesthesia. Traditional reversal agents, such as anticholinesterase inhibitors, work by increasing levels of the neurotransmitter acetylcholine. This non-specific mechanism can cause significant side effects, including cardiovascular issues, and is not reliably effective in cases of "profound block" where muscle function is completely suppressed (’733 Patent, col. 4:2-27).
  • The Patented Solution: The patent proposes a different approach using chemical chelators, specifically modified cyclodextrins, which are large, ring-shaped molecules. These modified cyclodextrins are designed to directly capture and encapsulate NMBA molecules in a "guest-host complex," thereby inactivating them without altering acetylcholine levels in the body (’733 Patent, col. 4:28-43; Abstract). The patent discloses a class of 6-mercapto-cyclodextrin derivatives with specific chemical side chains that enable this encapsulation.
  • Technical Importance: This direct encapsulation mechanism represented a novel way to reverse neuromuscular blockade, offering the potential for faster, more predictable recovery and an avoidance of the side effects associated with traditional anticholinesterase agents (Compl. ¶¶ 39-40).

Key Claims at a Glance

  • The complaint alleges infringement of one or more claims, including at least Claim 1, and notes that Defendant's notice letter did not contest infringement of claims 1-5, 9, 11-14, 20, and 21 (’733 Patent, Compl. ¶¶ 52-53).
  • The primary independent claims appear to be Claim 1 (a broad composition claim), Claim 6 (a kit claim), Claim 9 (a method of use claim), and Claim 11 (a specific compound claim). Claim 11 recites:
    • 6-Per-deoxy-6-per-(2-carboxyethyl)thio-γ-cyclodextrin,
    • or a pharmaceutically acceptable salt thereof.

III. The Accused Instrumentality

Product Identification

  • The accused instrumentalities are Aurobindo’s proposed generic sugammadex injection products at 200 mg/2 mL and 500 mg/5 mL concentrations, which are the subject of ANDA No. 214307 ("Aurobindo ANDA Products") (Compl. ¶8).

Functionality and Market Context

  • The Aurobindo ANDA Products are intended to be generic versions of Merck's Bridion® drug product (Compl. ¶42). The product is indicated for the reversal of neuromuscular blockade induced by rocuronium bromide and vecuronium bromide in adults undergoing surgery (Compl. ¶45). The complaint alleges that the active ingredient in the accused products is sugammadex (Compl. ¶48), which functions by directly encapsulating and inactivating neuromuscular blocking agents (Compl. ¶39).

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

  • Claim Chart Summary: The complaint’s infringement theory for Claim 11, which recites the specific compound known as sugammadex, is based on Defendant's ANDA submission.

RE44,733 Infringement Allegations

Claim Element (from Independent Claim 11) Alleged Infringing Functionality Complaint Citation Patent Citation
6-Per-deoxy-6-per-(2-carboxyethyl)thio-γ-cyclodextrin, or a pharmaceutically acceptable salt thereof. The complaint alleges that Defendant stated in its ANDA notice letter that the "Aurobindo ANDA Products contain sugammadex as an active ingredient." The complaint further identifies sugammadex as the common name for the claimed compound. ¶36, ¶48 col. 9:1-4
  • Identified Points of Contention:
    • Infringement: The complaint alleges that Defendant did not contest infringement of Claim 11 in its pre-suit notice letter (Compl. ¶53). If the accused product's active ingredient is indeed sugammadex sodium as alleged, the infringement analysis may be straightforward. The central dispute in the case will likely concern the patent's validity.
    • Validity Questions: The patent discloses and claims a specific molecule (sugammadex) within a broader class of modified cyclodextrins. The patent's own claims exclude several other specific cyclodextrin derivatives, suggesting a potentially crowded prior art field (’733 Patent, col. 19:28-44). A key question for the court will be whether the specific molecular structure of sugammadex would have been obvious to a person of ordinary skill in the art at the time of the invention, based on the known properties of other cyclodextrin-based chelators.

V. Key Claim Terms for Construction

For a claim reciting a specific chemical compound, such as Claim 11, disputes over claim construction are often minimal, as the chemical name itself defines the structure. The case will likely focus more on validity than on the meaning of claim terms. However, broader claims like Claim 1 contain terms that could be subject to interpretation.

  • The Term: "(C1-6)alkylene" (from Claim 1)
  • Context and Importance: This term defines the chemical linker between the cyclodextrin core and the active side chain. The interpretation of its scope is relevant to the breadth of the patent's other asserted claims and could be a factor in validity arguments concerning the range of compounds enabled by the specification.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification provides an explicit definition, stating that the term "means a branched or straight chain bivalent carbon radical containing 1-6 carbon atoms" and provides a non-exhaustive list of examples, including "methylene, ethylene... 1,6-hexanediyl" (’733 Patent, col. 5:20-27). This language may support a standard, broad chemical definition covering all structures with one to six carbon atoms.
    • Evidence for a Narrower Interpretation: A party seeking a narrower construction may point to the patent’s examples, which primarily feature shorter, unbranched linkers (e.g., ethyl in Example 4, propyl in Example 6). An argument could be made that the specification does not sufficiently enable or describe the full scope of all possible branched C1-6 alkylene linkers, potentially limiting the claim's effective scope to the types of structures actually made and tested.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges active inducement of infringement, stating that upon approval, Defendants will market and distribute the Aurobindo ANDA Products with a product label or insert containing instructions for administration. It is alleged that following these instructions by healthcare professionals would constitute direct infringement of the patent's method claims, and that Defendants intend to cause these acts (Compl. ¶59).
  • Willful Infringement: Willfulness is alleged based on Defendants having "full knowledge of the '733 patent" through the ANDA process and acting "without a reasonable basis for believing that they would not be liable for direct infringement" (Compl. ¶64). The basis for knowledge is the required Paragraph IV certification against an Orange Book-listed patent.

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

  • A core issue will be one of validity: Is Claim 11 of the ’733 patent, which recites the specific chemical compound sugammadex, invalid for obviousness over the prior art? The resolution will depend on the structural and functional differences between sugammadex and previously known cyclodextrin derivatives, and whether there was a motivation in the art to make the specific modifications claimed.
  • A key procedural question will be one of objective baselessness: Did the Defendants' pre-suit investigation provide an objectively reasonable basis for their Paragraph IV certification that the '733 patent is invalid or not infringed? The answer to this will determine the viability of Plaintiffs' claim for willful infringement and a potential award of attorney's fees.