DCT
1:25-cv-00807
Supernus Pharma Inc v. Appco Pharma LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Supernus Pharmaceuticals, Inc. (Delaware)
- Defendant: Appco Pharma LLC (New Jersey) and Somerset Therapeutics LLC (Delaware)
- Plaintiff’s Counsel: Faegre Drinker Biddle & Reath LLP; Haug Partners LLP
- Case Identification: 1:25-cv-00807, D. Del., 07/01/2025
- Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendants conduct business in the state, maintain continuous and systematic contacts, and, upon receiving FDA approval, will market and distribute the accused generic products in Delaware. Defendant Somerset Therapeutics LLC is a Delaware limited liability company.
- Core Dispute: Plaintiff alleges that Defendants' filing of an Abbreviated New Drug Application (ANDA) to market generic viloxazine extended-release capsules constitutes an act of infringement of six patents covering Plaintiff's branded drug, Qelbree®.
- Technical Context: The technology relates to pharmaceutical formulations of viloxazine and methods of using it for the treatment of Attention Deficit Hyperactivity Disorder (ADHD).
- Key Procedural History: This Hatch-Waxman litigation was initiated after Defendants filed ANDA No. 220326 and sent Plaintiff a Paragraph IV certification notice letter, asserting that the patents-in-suit are invalid or will not be infringed by their proposed generic product. The patents are listed in the FDA’s "Approved Drug Products with Therapeutic Equivalence Evaluations" (the "Orange Book") as covering Qelbree®. The complaint notes that a prior suit involving the same parties, patents, and ANDA was filed in the District of New Jersey.
Case Timeline
| Date | Event |
|---|---|
| 2008-09-05 | Priority Date for ’753, ’143, and ’523 Patents |
| 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 |
| 2025-05-21 | Defendants send first Paragraph IV Notice Letter to Plaintiff |
| 2025-06-09 | Defendants send second Paragraph IV Notice Letter to Plaintiff |
| 2025-06-26 | Plaintiff files prior suit in the District of New Jersey |
| 2025-07-01 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,358,204 - “Formulations of Viloxazine,” Issued June 7, 2016
The Invention Explained
- Problem Addressed: The patent addresses challenges in developing an extended-release formulation for viloxazine, a drug which has a "potentially high therapeutic dose" and a "relatively high in vivo clearance rate," making once-daily dosing difficult to achieve with conventional methods (Compl. ¶1; ’204 Patent, col. 1:41-47).
- The Patented Solution: The invention provides a modified-release formulation that combines different types of drug release components. Specifically, it discloses a pulsatile release achieved by combining an immediate-release (IR) component with an extended-release (XR) component, which itself may have a controlling coating, to achieve a therapeutic effect over a prolonged period (’204 Patent, Abstract; col. 2:59-67).
- Technical Importance: This formulation technology enables once- or twice-daily dosing of viloxazine, which may improve patient compliance and provide more stable plasma concentrations compared to older, immediate-release versions that required more frequent administration (’204 Patent, col. 3:12-20).
Key Claims at a Glance
- The complaint asserts infringement of one or more claims of the ’204 patent (Compl. ¶61). Independent claim 1 is representative of the formulation technology.
- Claim 1 Elements:
- A pharmaceutical formulation comprising:
- (a) an immediate release (IR) component comprising an inert core and a layer comprising viloxazine... surrounding the core, and
- (b) an extended release (XR) component comprising: (i) an inert core, (ii) a first layer comprising viloxazine... surrounding the core, and (iii) a second layer comprising a release rate controlling compound and a pore former... surrounding the first layer.
- The complaint does not specify assertion of dependent claims but makes a general allegation against the patent (Compl. ¶61).
U.S. Patent No. 9,603,853 - “Formulations of Viloxazine,” Issued March 28, 2017
The Invention Explained
- Problem Addressed: As with the related ’204 Patent, this patent addresses the need for a viloxazine formulation suitable for once- or twice-daily administration to treat CNS disorders like ADHD (’853 Patent, col. 1:41-47).
- The Patented Solution: The invention is a method of treating ADHD by administering a specific modified-release formulation of viloxazine. The formulation described is a pulsatile dosage form that contains both immediate-release and extended-release components, designed to achieve a particular pharmacokinetic profile suitable for managing ADHD symptoms throughout the day (’853 Patent, Abstract; col. 27:27-41).
- Technical Importance: By claiming a method of treatment using a specific formulation type, the patent protects not just the drug product itself but also its approved use, providing a different layer of protection from generic competition (’853 Patent, col. 27:27-41).
Key Claims at a Glance
- The complaint asserts infringement of one or more claims of the ’853 patent (Compl. ¶83). Independent claim 1 is representative of the claimed method.
- Claim 1 Elements:
- A method of treating ADHD or major depressive disorder in a mammalian subject in need thereof, the method comprising administration to the subject of a formulation comprising:
- (a) an immediate release (IR) component comprising an inert core and a layer comprising viloxazine... and
- (b) an extended release (XR) component comprising: (i) an inert core, (ii) a first layer comprising viloxazine..., and (iii) a second layer comprising a release rate controlling compound and a pore former...
- The complaint does not specify assertion of dependent claims but makes a general allegation against the patent (Compl. ¶83).
U.S. Patent No. 9,662,338 - “Formulations of Viloxazine,” Issued May 30, 2017
- Technology Synopsis: This patent, part of the same family as the ’204 and ’853 patents, claims pharmaceutical formulations of viloxazine. It is directed to a specific composite formulation containing both immediate-release and extended-release multiparticulates to achieve a desired pharmacokinetic profile for treating CNS disorders (’338 Patent, Abstract).
- Asserted Claims: One or more claims (Compl. ¶105).
- Accused Features: Defendants' ANDA Products, which are extended-release viloxazine capsules, are alleged to be or contain the claimed formulation (Compl. ¶¶106, 111).
U.S. Patent No. 11,324,753 - “Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD),” Issued May 10, 2022
- Technology Synopsis: This patent claims a method for treating ADHD by administering viloxazine. The invention is based on the discovery that viloxazine exhibits antagonist activity at specific serotonin receptors (5-HT7 and 5HT1B), a mechanism of action purported to be effective for ADHD treatment (’753 Patent, col. 1:29-33, 53-61).
- Asserted Claims: One or more claims (Compl. ¶127).
- Accused Features: The administration of Defendants' ANDA Products for ADHD treatment as will be instructed by the proposed product labeling (Compl. ¶¶128, 136).
U.S. Patent No. 11,458,143 - “Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD),” Issued October 4, 2022
- Technology Synopsis: A continuation of the ’753 patent, this patent also claims a method of treating ADHD with viloxazine. The claimed method consists of administering a formulation of viloxazine or a pharmaceutically acceptable salt thereof to a patient suffering from ADHD (’143 Patent, Abstract; col. 5:53-60).
- Asserted Claims: One or more claims (Compl. ¶149).
- Accused Features: The administration of Defendants' ANDA Products for ADHD treatment as will be instructed by the proposed product labeling (Compl. ¶¶150, 158).
U.S. Patent No. 12,121,523 - “Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD),” Issued October 22, 2024
- Technology Synopsis: Part of the same family as the ’753 and ’143 patents, this patent claims methods of treating a patient with a mood or affective disorder that is co-morbid with ADHD. The method involves administering a therapeutically effective amount of viloxazine (’523 Patent, col. 7:35-43).
- Asserted Claims: One or more claims (Compl. ¶171).
- Accused Features: The administration of Defendants' ANDA Products for ADHD, which may be co-morbid with mood disorders, as will be instructed by the proposed product labeling (Compl. ¶¶172, 180).
III. The Accused Instrumentality
Product Identification
- Defendants' viloxazine extended-release capsules in 100 mg, 150 mg, and 200 mg dosage strengths, for which ANDA No. 220326 was submitted to the FDA (Compl. ¶¶7, 46).
Functionality and Market Context
- The complaint alleges that the Defendants' ANDA Products are generic versions of Plaintiff's Qelbree® product and have been represented to the FDA as bioequivalent (Compl. ¶¶45, 47). The proposed prescribing information for the ANDA Products allegedly indicates them for the treatment of ADHD in adults and pediatric patients 6 years and older, with dosing instructions that mirror those for Qelbree® (Compl. ¶¶50, 51). The mechanism of action is described as inhibiting the reuptake of norepinephrine (Compl. ¶52).
No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
'204 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A pharmaceutical formulation, comprising: | Defendants' ANDA Products are alleged to be extended-release viloxazine formulations that are bioequivalent to Qelbree® and will infringe upon approval. | ¶65, ¶66 | col. 27:27-28 |
| (a) an immediate release (IR) component comprising an inert core and a layer comprising viloxazine... | The complaint does not specify the components of the ANDA product but alleges that to be bioequivalent to Qelbree®, it must practice the claimed formulation structure. | ¶47, ¶61 | col. 27:29-32 |
| (b) an extended release (XR) component comprising: (i) an inert core, (ii) a first layer comprising viloxazine..., and (iii) a second layer comprising a release rate controlling compound and a pore former... | As with the IR component, infringement is alleged based on the product's overall function as a bioequivalent extended-release formulation, implying it contains the claimed XR structure. | ¶47, ¶61 | col. 27:33-41 |
Identified Points of Contention
- Structural Questions: The complaint asserts infringement based on the filing of the ANDA and the product's bioequivalence to Qelbree®, without detailing the specific formulation of the accused product (Compl. ¶¶47, 65). A primary point of contention will be whether Defendants' formulation, once disclosed, contains the specific multi-layered "IR component" and "XR component" structures as recited in claim 1.
- Evidentiary Questions: What evidence does the complaint provide that achieving bioequivalence necessarily requires copying the claimed formulation structure, as opposed to achieving a similar pharmacokinetic profile through an alternative, non-infringing design?
'853 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of treating ADHD... comprising administration to the subject of a formulation... | Defendants' ANDA Products will have labeling instructing physicians and patients to administer the drug for the treatment of ADHD. | ¶50, ¶51, ¶93 | col. 27:27-28 |
| ...the formulation comprising: (a) an immediate release (IR) component... and (b) an extended release (XR) component... | The act of administering the ANDA product, which is alleged to be the claimed formulation, will constitute direct infringement by end-users. Defendants are alleged to induce this infringement. | ¶92, ¶93 | col. 27:29-41 |
Identified Points of Contention
- Inducement Questions: Infringement of this method claim hinges on inducement. A key question will be whether the instructions in the proposed label for Defendants' ANDA Product will encourage, recommend, or promote administration in a manner that meets all limitations of the claimed method, including the use of a formulation with the specific IR and XR components.
- Scope Questions: This analysis is linked to the infringement analysis of the ’204 patent. Whether end-users directly infringe the method claim depends on whether the product they administer is, in fact, the formulation claimed.
V. Key Claim Terms for Construction
Term: "immediate release (IR) component" / "extended release (XR) component"
- (from claims of the ’204 and ’853 patents)
- Context and Importance: The determination of infringement for the formulation patents will depend entirely on whether Defendants' product contains structures that fall within the scope of these terms. Practitioners may focus on these terms because the complaint lacks specific details on the accused product's formulation, making the breadth of these definitions a central issue.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes the invention as encompassing various combinations of release profiles, stating the goal is to achieve a 'pulsatile release' which may suggest that any formulation structure achieving this functional goal could be covered (’204 Patent, col. 2:64-65).
- Evidence for a Narrower Interpretation: Claim 1 of the ’204 patent recites a very specific structure for each component (e.g., "an inert core and a layer comprising viloxazine" for the IR component; a "first layer" and a "second layer" for the XR component). This detailed recitation may support a narrower construction limited to multiparticulates with these exact layered structures.
Term: "antagonizing 5-HT7 and 5HT1B receptor activity"
- (from claim 1 of the ’753 patent)
- Context and Importance: This term defines the novel mechanism of action that forms the basis of the method-of-use patents. Infringement will require showing that the administration of the accused product, as instructed by its label, results in this specific biological activity.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes viloxazine as "exhibiting" this activity and explains that this discovery makes it effective for ADHD (’753 Patent, col. 1:53-61). This could support an interpretation where simply administering viloxazine inherently performs the 'antagonizing' step.
- Evidence for a Narrower Interpretation: The detailed description provides specific experimental data showing viloxazine's antagonist effect in functional assays (’753 Patent, col. 5:5-12; Fig. 3). A defendant may argue that "antagonizing" requires achieving a specific, measurable level of receptor blockade in a patient, a higher bar than simply administering the drug.
VI. Other Allegations
Indirect Infringement
- The complaint alleges both induced and contributory infringement for all patents-in-suit. Inducement is primarily based on the allegation that Defendants' proposed product labeling will instruct physicians and patients to administer the drug for the treatment of ADHD, which will directly infringe the method claims and involve the use of the infringing formulation (Compl. ¶¶70-73, 92-95). Contributory infringement is alleged on the basis that the ANDA Products are a material part of the patented inventions and are not staple articles of commerce suitable for substantial non-infringing use (Compl. ¶¶74, 96).
Willful Infringement
- Willfulness is alleged based on Defendants' pre-suit knowledge of the patents-in-suit. The complaint asserts that this knowledge is demonstrated by Defendants' act of filing an ANDA containing a Paragraph IV certification that specifically identified each of the asserted patents (Compl. ¶¶75, 97).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of structural correspondence: will discovery show that the Defendants' generic formulation contains the specific multi-layered, multi-component structures required by the asserted formulation claims, or does it achieve bioequivalence through an alternative design that falls outside the literal scope of those claims?
- A second central issue will be one of induced method: does the proposed product label for the generic drug do more than just indicate treatment for ADHD? Does it actively instruct or encourage a method of use that encompasses the specific functional limitations of the method patents, such as the "antagonizing" of specific serotonin receptors?
- A key evidentiary question will be one of bioequivalence versus infringement: to what extent can the Plaintiff rely on the ANDA's certification of bioequivalence to infer that the accused product necessarily infringes the specific formulation structures claimed in its patents, particularly at the pre-discovery stage?