DCT

2:25-cv-18683

Supernus Pharmaceuticals Inc v. Macleods Pharmaceuticals Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-18683, D.N.J., 12/16/2025
  • Venue Allegations: Venue is asserted based on Defendant Macleods USA, Inc. maintaining its principal place of business in New Jersey and both defendants conducting substantial business in the district. The filing of an Abbreviated New Drug Application (ANDA) is alleged to be an act purposefully directed at the district, with the intent to market and sell the accused product there.
  • Core Dispute: Plaintiff alleges that Defendants’ filing of an ANDA to market a generic version of Plaintiff's Qelbree® product constitutes infringement of six patents related to formulations and methods of using viloxazine for treating Attention Deficit Hyperactivity Disorder (ADHD).
  • Technical Context: The technology concerns extended-release pharmaceutical formulations designed to provide controlled delivery of viloxazine, a drug used for treating ADHD, to enable once- or twice-daily dosing.
  • Key Procedural History: The complaint notes a prior, pending lawsuit (Civ. No. 2:25-cv-15399) filed by the Plaintiff against the same Defendants concerning the same ANDA, but for different proposed dosages (150 mg and 200 mg). This action appears to concern the 100 mg dosage form of the same proposed generic product.

Case Timeline

Date Event
2008-09-05 Priority Date for ’753, ’143, and ’523 Patents
2011-01-01 Macleods Pharma USA, Inc. commences U.S. operations
2012-02-08 Priority Date for ’204, ’853, and ’338 Patents
2016-06-07 U.S. Patent No. 9,358,204 Issues
2017-03-28 U.S. Patent No. 9,603,853 Issues
2017-05-30 U.S. Patent No. 9,662,338 Issues
2022-05-10 U.S. Patent No. 11,324,753 Issues
2022-10-04 U.S. Patent No. 11,458,143 Issues
2024-10-22 U.S. Patent No. 12,121,523 Issues
2025-08-01 Defendants send Plaintiff "August Notice Letter" regarding Paragraph IV Certifications
2025-09-09 Plaintiff files prior infringement suit against Defendants (Civ. No. 2:25-15399)
2025-11-20 Defendants send Plaintiff "November Notice Letter" regarding Paragraph IV Certifications
2025-12-16 Complaint Filed

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

U.S. Patent No. 9,358,204 - "Formulations of Viloxazine," Issued June 7, 2016 (’204 Patent)

The Invention Explained

  • Problem Addressed: The patent addresses challenges in developing an extended-release formulation for viloxazine, which has a potentially high therapeutic dose and a high in-vivo clearance rate in humans, typically requiring multiple daily doses ('204 Patent, col. 1:41-47).
  • The Patented Solution: The invention provides modified-release formulations that control the delivery of viloxazine over a prolonged period. This is achieved through various formulation strategies, including combining immediate release (IR), extended release (XR), and delayed release (DR) components into a single dosage form, such as a matrix tablet or multi-particulate capsules ('204 Patent, col. 2:1-4, col. 3:47-51). The goal is to provide therapeutic drug levels for about 4 to 24 hours from a single administration ('204 Patent, col. 3:47-51).
  • Technical Importance: These controlled-release formulations are intended to allow for once- or twice-daily dosing, which may improve patient compliance and reduce side effects compared to immediate-release versions requiring more frequent administration (Compl. ¶85).

Key Claims at a Glance

  • The complaint does not identify specific claims asserted against the Defendants, alleging infringement of "one or more claims" of the '204 patent (Compl. ¶77).
  • Independent claim 1, as a representative example, is a method of treating ADHD or major depressive disorder by administering a formulation comprising:
    • An immediate release (IR) component comprising an inert core and a layer with viloxazine.
    • An extended release (XR) component comprising an inert core, a first layer with viloxazine, and a second layer with a release rate controlling compound and a pore former.
  • The complaint reserves the right to assert additional claims, including dependent claims (Compl. ¶71).

U.S. Patent No. 9,603,853 - "Formulations of Viloxazine," Issued March 28, 2017 (’853 Patent)

The Invention Explained

  • Problem Addressed: Similar to the ’204 Patent, this patent addresses the need for a controlled-release formulation of viloxazine suitable for once- or twice-daily administration to overcome the drug's short elimination half-life ('853 Patent, col. 1:30-33, col. 1:41-47).
  • The Patented Solution: The invention describes a pharmaceutical formulation with an extended-release (XR) component built upon an inert core. This core is layered first with the active drug (viloxazine) and then with a second layer containing a release rate controlling compound and a "pore former," which work together to modulate the drug's release over time ('853 Patent, Abstract; col. 2:50-65).
  • Technical Importance: This specific multi-layer pellet design provides a method for achieving a consistent, extended release profile necessary for less frequent dosing of viloxazine (Compl. ¶99).

Key Claims at a Glance

  • The complaint does not identify specific claims, alleging infringement of "one or more claims" of the '853 patent (Compl. ¶93).
  • Independent claim 1, as a representative example, is a method of treating ADHD or major depressive disorder by administering a formulation comprising an XR component with a specific structure:
    • An inert core.
    • A first layer surrounding the core comprising viloxazine.
    • A second layer surrounding the first layer comprising a release rate controlling compound and a pore former.
  • The complaint reserves the right to assert additional claims, including dependent claims (Compl. ¶93).

U.S. Patent No. 9,662,338 (’338 Patent) - "Formulations of Viloxazine," Issued May 30, 2017

  • Technology Synopsis: The ’338 Patent, part of the same family as the ’204 and ’853 patents, discloses extended-release viloxazine formulations. It specifically claims a formulation composed of a plurality of particles, each comprising a core with viloxazine and a release-controlling coating, designed to provide therapeutic levels for at least 8 to 16 hours.
  • Asserted Claims: The complaint alleges infringement of one or more unspecified claims (Compl. ¶115).
  • Accused Features: The accused features are the entirety of the Defendants' ANDA Product, which is an extended-release formulation alleged to be bioequivalent to Plaintiff's product covered by the patent (Compl. ¶54, ¶121).

U.S. Patent No. 11,324,753 (’753 Patent) - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued May 10, 2022

  • Technology Synopsis: This patent is based on the "unexpected discovery" that viloxazine exhibits antagonist activity at the 5-HT7 and 5-HT1B serotonin receptors, in addition to its known activity as a norepinephrine reuptake inhibitor ('753 Patent, col. 1:27-31, col. 2:57-61). The patent claims a method of treating ADHD by administering viloxazine to antagonize both of these receptors.
  • Asserted Claims: The complaint alleges infringement of one or more unspecified claims (Compl. ¶137).
  • Accused Features: The accused feature is the act of seeking FDA approval to market a generic viloxazine product with labeling that will instruct its use for treating ADHD, which Plaintiff alleges will directly and indirectly infringe the patented method (Compl. ¶143, ¶146).

U.S. Patent No. 11,458,143 (’143 Patent) - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued October 4, 2022

  • Technology Synopsis: A continuation of the ’753 Patent, the ’143 Patent also claims methods of treating ADHD with viloxazine. The claims focus on administering a formulation of viloxazine, without explicitly reciting the receptor antagonism mechanism, to treat ADHD.
  • Asserted Claims: The complaint alleges infringement of one or more unspecified claims (Compl. ¶159).
  • Accused Features: The accused feature is the intended use of the Defendants' ANDA Product for the treatment of ADHD as directed by its proposed labeling (Compl. ¶165, ¶168).

U.S. Patent No. 12,121,523 (’523 Patent) - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued October 22, 2024

  • Technology Synopsis: Also in the same family as the ’753 Patent, the ’523 Patent claims methods for treating ADHD and co-morbid mood or affective disorders (such as anxiety or depression) by administering viloxazine.
  • Asserted Claims: The complaint alleges infringement of one or more unspecified claims (Compl. ¶181).
  • Accused Features: The accused feature is the proposed use of the Defendants' ANDA Product to treat ADHD, which the proposed label indicates (Compl. ¶57), and which may be used in patients with co-morbid disorders covered by the patent's claims (Compl. ¶187, ¶190).

III. The Accused Instrumentality

  • Product Identification: The accused instrumentality is Defendants' ANDA No. 220570 Product ("ANDA Product"), described as "generic viloxazine extended-release oral capsules, containing 100 mg of viloxazine" (Compl. ¶15).
  • Functionality and Market Context: The ANDA Product is an extended-release pharmaceutical designed for the treatment of ADHD in adults and pediatric patients 6 years and older (Compl. ¶57). The complaint alleges Defendants have represented to the FDA that their ANDA Product is bioequivalent to Supernus's approved drug, Qelbree®, which serves as the Reference Listed Drug (Compl. ¶52, ¶54). The proposed prescribing information for the ANDA Product allegedly includes dosage and administration instructions that mirror those for Qelbree®, including a 100 mg starting dosage for certain pediatric patients (Compl. ¶58). The product's mechanism of action is stated to be through inhibiting the reuptake of norepinephrine (Compl. ¶59).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not contain claim charts or detailed infringement contentions mapping elements of the accused product to specific claim limitations. Infringement is alleged based on the act of filing the ANDA under 35 U.S.C. § 271(e)(2), which seeks approval to market a generic product that is a bioequivalent copy of Plaintiff's patented Qelbree® drug and will be sold with a substantially similar label for the same patented use (Compl. ¶54, ¶75, ¶79). The following summary is based on these allegations for representative claims.

’204 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method of treating ADHD...comprising administering to the subject in need thereof a formulation... Defendants' ANDA seeks approval to market a product "indicated for the treatment of Attention-Deficit Hyperactivity Disorder (ADHD)," and the proposed labeling allegedly instructs this use. ¶57, ¶78 col. 7:27-31
...comprising: (a) an immediate release (IR) component...and (b) an extended release (XR) component... The ANDA Product is identified as "viloxazine extended-release oral capsules," which necessarily contains components that modify the drug's release profile over time. The complaint does not provide further detail on the specific components. ¶15, ¶53 col. 7:32-47

’853 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method of treating ADHD...comprising administering...a formulation comprising: an extended release (XR) component... Defendants' ANDA Product is an extended-release formulation intended for the treatment of ADHD. ¶15, ¶57, ¶100 col. 7:42-45
...comprising: (i) an inert core, (ii) a first layer surrounding the core comprising viloxazine, and (iii) a second layer...comprising a release rate controlling compound and a pore former... The complaint alleges the ANDA product is bioequivalent to Qelbree®, which is covered by the patent. However, it does not provide a technical breakdown of the generic product's formulation to map to these specific structural elements. ¶54, ¶99 col. 7:46-56

Identified Points of Contention

  • Scope Questions: A central issue may be whether the specific formulation of Defendants' ANDA Product meets the structural limitations of the asserted claims. For instance, for the '853 Patent, a question for the court could be whether Defendants' formulation contains an "inert core" and distinct "first layer" and "second layer" with a "pore former" as those terms are construed in the context of the patent.
  • Technical Questions: For the method-of-use patents ('753, '143, '523), a key question will be one of induced infringement. For the '753 Patent, what evidence suggests that administering viloxazine as described on the proposed label inherently causes the claimed "antagonizing [of] 5-HT7 and 5HT1B receptor activity," and whether instructing the treatment of ADHD is sufficient to induce infringement of this mechanistically-defined method?

V. Key Claim Terms for Construction

Term: "extended release (XR) component" (’204 Patent)

  • Context and Importance: The definition of this term is fundamental, as the dispute centers on an extended-release formulation. Defendants may argue that their formulation's release mechanism, or the components that achieve it, fall outside the patent's definition of an "XR component."
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification defines "extended release" functionally as a formulation that releases at least 80% of the drug over a period of at least 2 hours, which could be read to cover a wide variety of release mechanisms (’204 Patent, col. 5:30-36).
    • Evidence for a Narrower Interpretation: A narrower construction might be argued by pointing to the specific structures described in the patent, such as the multi-layer pellet structure in claim 1(b) or the specific polymers listed as "release rate controlling compounds" ('204 Patent, col. 6:13-24).

Term: "pore former" (’853 Patent)

  • Context and Importance: This term describes a specific excipient in the claimed coating layer responsible for modulating drug release. Practitioners may focus on this term because the Defendants could argue their formulation achieves extended release through a different mechanism or uses an excipient that does not function as a "pore former."
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent does not provide an explicit definition but lists examples of pore formers, including "povidone, hypromellose, hydroxyethyl cellulose, hydroxypropyl cellulose, organic acids and salts" ('853 Patent, col. 10:48-51). This list could be interpreted as exemplary rather than exhaustive.
    • Evidence for a Narrower Interpretation: Defendants could argue that the term should be limited to substances that function primarily by dissolving to create physical pores in the coating, potentially excluding other types of release-modifying agents.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents. Inducement is primarily based on the allegation that Defendants' proposed product labeling will instruct and encourage physicians and patients to administer the ANDA Product in a manner that directly infringes the patented methods of treatment and use of the claimed formulations (Compl. ¶82, ¶104). Contributory infringement is alleged on the basis that the ANDA Product is a material part of the patented inventions, is not a staple article of commerce, and is made for an infringing use (Compl. ¶84, ¶106).
  • Willful Infringement: Willfulness is alleged for all asserted patents. The basis for this allegation is Defendants' knowledge of the patents-in-suit, evidenced by their filing of a Paragraph IV certification with the FDA that specifically referenced each patent (Compl. ¶85, ¶107). The complaint alleges that despite this knowledge, Defendants intend to engage in infringing activities.

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

  • A core issue will be one of structural equivalence: Will the specific, currently undisclosed formulation of the Defendants' generic product contain the precise structural elements (e.g., "inert core," "second layer," "pore former") required by the asserted claims of the formulation patents ('204, '853, '338) once those terms are construed by the court?
  • A second central question will be one of induced infringement for method claims: For the patents claiming a method of treatment ('753, '143, '523), can infringement be induced by a product label that instructs the treatment of ADHD, even if the label does not describe the specific underlying biological mechanism (i.e., serotonin receptor antagonism) recited in some of the claims?
  • Finally, a key defense question will be one of validity: As this case arises from a Paragraph IV certification, Defendants have asserted that the patents-in-suit are invalid and/or unenforceable. The case will therefore likely involve a substantive challenge to the patentability of the claimed formulations and methods in light of prior art.