DCT
1:25-cv-00880
Supernus Pharma Inc v. Creekwood Pharma LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Supernus Pharmaceuticals, Inc. (Delaware)
- Defendant: Creekwood Pharmaceuticals, LLC (Delaware)
- Plaintiff’s Counsel: Faegre Drinker Biddle & Reath LLP; Haug Partners LLP
- Case Identification: 1:25-cv-00880, D. Del., 07/15/2025
- Venue Allegations: Plaintiff alleges venue is proper because Defendant is a Delaware LLC that transacts business in the state and, upon FDA approval, intends to market and sell the accused products in the district.
- Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) for generic viloxazine extended-release capsules constitutes an act of infringement of six patents covering formulations of viloxazine and its use in treating Attention Deficit/Hyperactivity Disorder (ADHD).
- Technical Context: The dispute concerns extended-release pharmaceutical formulations designed to provide controlled delivery of an active ingredient over time, a technology crucial for improving patient compliance and managing therapeutic effects for chronic conditions like ADHD.
- Key Procedural History: Plaintiff notes it previously filed a related action in the District of New Jersey against Defendant on July 11, 2025, asserting infringement of the same patents based on the same ANDA. The instant case was filed in Delaware to ensure statutory and regulatory periods under the Hatch-Waxman Act are maintained.
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 |
| 2025-06-04 | Defendant sends Paragraph IV Notice Letter to Plaintiff |
| 2025-07-11 | Plaintiff files prior related action in D.N.J. |
| 2025-07-15 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,358,204 - "Formulations of Viloxazine"
The Invention Explained
- Problem Addressed: The patent addresses the challenge of creating an extended-release formulation for viloxazine, a drug with a potentially high therapeutic dose and a relatively high in vivo clearance rate, which would typically require frequent dosing (’204 Patent, col. 1:41-47).
- The Patented Solution: The invention provides modified-release formulations that control the delivery of viloxazine over an extended period. This is achieved through various structures, including multi-particulate systems that can combine immediate-release (IR), extended-release (XR), and delayed-release (DR) components to achieve a specific pharmacokinetic profile, allowing for once- or twice-daily dosing (’204 Patent, col. 2:1-17).
- Technical Importance: An effective extended-release formulation improves patient adherence to the treatment regimen, which is particularly important for chronic conditions, by reducing the dosing frequency from multiple times per day to once or twice per day (’204 Patent, col. 3:12-24).
Key Claims at a Glance
The complaint does not identify specific asserted claims. Independent claim 1 is representative of the formulation technology.
- A pharmaceutical formulation comprising:
- (a) an immediate release (IR) component comprising an inert core and a layer of viloxazine surrounding the core; and
- (b) an extended release (XR) component comprising an inert core, a first layer of viloxazine, and a second layer with a "release rate controlling compound" and a "pore former" in a specific weight ratio surrounding the first layer;
- where the formulation contains 25% to 75% viloxazine by weight and releases at least 80% of the drug over at least 2 hours in vitro.
U.S. Patent No. 11,324,753 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
The Invention Explained
- Problem Addressed: The patent addresses the need for effective treatments for ADHD and related disorders (’753 Patent, col. 1:21-23).
- The Patented Solution: The invention is based on the discovery that viloxazine, in addition to its known activity as a norepinephrine reuptake inhibitor, also exhibits antagonist activity at the 5-HT1B and 5-HT7 serotonin receptors. The patent claims a method of treating ADHD by administering viloxazine to achieve this dual antagonism, proposing this as a novel mechanism of action (’753 Patent, col. 2:56-62).
- Technical Importance: This patent purports to identify a previously unknown pharmacological mechanism for viloxazine's efficacy in ADHD, potentially distinguishing it from other ADHD treatments and providing a basis for its use with a potentially improved side-effect profile (’753 Patent, col. 5:29-44).
Key Claims at a Glance
The complaint does not identify specific asserted claims. Independent claim 1 is representative of the method of use technology.
- A method of antagonizing 5-HT7 and 5HT1B receptor activity in a patient suffering from ADHD,
- consisting of administering a therapeutically effective amount of viloxazine,
- wherein the administration antagonizes both receptors.
U.S. Patent No. 9,603,853 - "Formulations of Viloxazine"
- Technology Synopsis: This patent, related to the ’204 Patent, also describes modified-release formulations of viloxazine. It claims formulations comprising an immediate-release component and an extended-release component, designed to provide therapeutic levels of the drug over an extended period.
- Asserted Claims: The complaint makes general allegations against the patent (Compl. ¶¶ 75-76).
- Accused Features: The accused features are the formulation characteristics of Defendant's generic viloxazine extended-release capsules (Compl. ¶¶ 39-41).
U.S. Patent No. 9,662,338 - "Formulations of Viloxazine"
- Technology Synopsis: This patent, also in the same family as the ’204 Patent, discloses extended-release formulations of viloxazine. The claims cover compositions that provide a specific in vivo plasma concentration profile after administration.
- Asserted Claims: The complaint makes general allegations against the patent (Compl. ¶¶ 94-95).
- Accused Features: The accused features are the formulation and resulting pharmacokinetic profile of Defendant's generic viloxazine extended-release capsules (Compl. ¶¶ 39-41).
U.S. Patent No. 11,458,143 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
- Technology Synopsis: This patent, related to the ’753 Patent, claims methods of treating ADHD. It is based on the same discovery of viloxazine's antagonist activity at serotonin receptors in addition to its norepinephrine reuptake inhibition.
- Asserted Claims: The complaint makes general allegations against the patent (Compl. ¶¶ 132-133).
- Accused Features: The accused feature is the act of administering Defendant’s product for the treatment of ADHD as instructed by its proposed label (Compl. ¶¶ 44, 134-136).
U.S. Patent No. 12,121,523 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
- Technology Synopsis: This patent, also related to the ’753 Patent, claims methods for treating mood or affective disorders that are co-morbid with ADHD by administering viloxazine. This leverages the same pharmacological mechanism described in the parent patent.
- Asserted Claims: The complaint makes general allegations against the patent (Compl. ¶¶ 151-152).
- Accused Features: The accused feature is the act of administering Defendant’s product for the treatment of ADHD, which may have co-morbid disorders, as instructed by its proposed label (Compl. ¶¶ 44, 153-155).
III. The Accused Instrumentality
Product Identification
- Defendant's generic viloxazine extended-release oral capsules, containing 100 mg and 200 mg of viloxazine, for which Defendant filed Abbreviated New Drug Application No. 220277 with the FDA (Compl. ¶¶ 7, 40).
Functionality and Market Context
- The complaint alleges that Defendant's ANDA Products are generic versions of Plaintiff's Qelbree® extended-release capsules and have been represented to the FDA as bioequivalent (Compl. ¶¶ 39, 41). The proposed prescribing information for the accused products indicates them for the "treatment of Attention-Deficit Hyperactivity Disorder (ADHD) in adults and pediatric patients 6 years and older" (Compl. ¶44). The label allegedly includes specific dosage and administration instructions for different patient populations and describes the product's mechanism of action as inhibiting the reuptake of norepinephrine (Compl. ¶¶ 45-46).
No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint does not provide a detailed element-by-element infringement analysis for the asserted formulation patents ('204, '853, '338). The infringement theory is predicated on Defendant's ANDA Products being a generic version of and bioequivalent to Plaintiff's Qelbree® product, which is listed in the FDA's Orange Book as being covered by the patents-in-suit (Compl. ¶¶ 32, 39, 41). The act of infringement is the submission of the ANDA itself seeking approval to market this formulation (Compl. ¶54).
For the method of use patents, the infringement theory is based on inducement, stemming from the proposed product label that instructs physicians and patients to use the generic product to treat ADHD.
'753 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of antagonizing 5-HT7 and 5HT1B receptor activity in a patient suffering from ADHD... | Defendant’s proposed product label states that its ANDA Products are "indicated for the treatment of Attention-Deficit Hyperactivity Disorder (ADHD)". | ¶44 | col. 1:15-18 |
| ...consisting of administering to the patient in need thereof a therapeutically effective amount of viloxazine... | Defendant seeks approval to market and sell 100 mg and 200 mg extended-release capsules of viloxazine, with a label providing specific dosage instructions for treating ADHD. | ¶¶7, 40, 45 | col. 7:13-18 |
| ...wherein the administration antagonizes both receptors. | This is an inherent pharmacological result of administering viloxazine for the treatment of ADHD, as disclosed in the patent's specification. | ¶¶46-47 | col. 2:56-62 |
- Identified Points of Contention:
- Scope Questions: For the formulation patents ('204, '853, '338), a central question will be whether Defendant's specific formulation falls within the scope of the patent claims. This will involve construction of terms describing the formulation's structure, such as "extended release (XR) component," and its constituent parts, such as "release rate controlling compound" and "pore former."
- Technical Questions: The infringement analysis for the formulation patents will depend entirely on the technical details of Defendant's ANDA, which are not public. The dispute will focus on whether the materials used, their ratios, and the physical structure of Defendant's generic capsules meet every limitation of the asserted claims. For the method patents ('753, '143, '523), a key question may surround the issue of validity, specifically whether treating ADHD with viloxazine was obvious in light of prior art disclosing its properties as an antidepressant.
V. Key Claim Terms for Construction
The Term: "extended release (XR) component" (from '204 Patent, claim 1)
- Context and Importance: The definition of this structural term is central to the infringement analysis for the formulation patents. Whether Defendant’s product infringes will depend on whether its formulation contains a structure that meets the specific multi-part definition of this term as recited in the claims.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes multiple ways to achieve extended release, including both "Matrix Systems" and "Drug-Layered Systems," suggesting the concept is not limited to a single embodiment (’204 Patent, col. 7:7-30).
- Evidence for a Narrower Interpretation: Claim 1 itself provides a highly detailed definition, requiring an "inert core," a "first layer comprising viloxazine," and a "second layer comprising a release rate controlling compound and a pore former in a weight ratio of 19:1 to 8.5:1.5." This language may support a narrow construction limited to this specific layered structure.
The Term: "consisting of" (from '753 Patent, claim 1)
- Context and Importance: Practitioners may focus on this term because "consisting of" is a term of art in patent law that closes a claim to any elements not recited. In this method claim, it means the claimed method of antagonizing receptors consists only of the single step of "administering...viloxazine."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: In the context of a method claim, courts typically interpret "consisting of" to mean the active steps of the method, not precluding unrecited but conventional steps, such as a patient taking the medication with water. The focus would be on viloxazine being the sole active agent administered for the claimed purpose.
- Evidence for a Narrower Interpretation: A defendant could argue that this language makes the claim exceptionally narrow, though such an argument is less likely to prevail on infringement than on validity. The primary dispute is more likely to concern whether this narrowly claimed method was obvious, rather than whether the accused infringer performs additional steps.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all six patents. The inducement allegations are based on the proposed product label for Defendant's ANDA Products, which allegedly will instruct and encourage doctors and patients to use the product in an infringing manner (e.g., Compl. ¶¶ 61, 78, 99, 118, 137, 156). Contributory infringement is alleged on the basis that Defendant's product is a material part of the patented inventions and is not a staple article of commerce suitable for substantial non-infringing use (e.g., Compl. ¶¶ 63, 82, 101, 120, 139, 158).
- Willful Infringement: The complaint alleges willful infringement for all six patents. The basis for willfulness is Defendant's alleged knowledge of the patents, as evidenced by its filing of an ANDA with a Paragraph IV certification that specifically referenced each of the patents-in-suit (e.g., Compl. ¶¶ 64, 83, 102, 121, 140, 159).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of technical equivalence: Does the specific formulation of Creekwood’s proposed generic product, as detailed in its confidential ANDA, contain the multi-component structures (e.g., an "immediate release component" and a distinct "extended release component") with the specific compositions (e.g., "pore formers" and "release rate controlling compounds") required by the asserted formulation patent claims?
- A second central issue will be one of validity: Can Creekwood demonstrate with clear and convincing evidence that the claimed methods of treating ADHD with viloxazine were obvious or anticipated by prior art, particularly given viloxazine's earlier established use as a norepinephrine reuptake inhibitor for depression?
- A key question of claim scope will be how the court construes the detailed structural limitations in the formulation claims. The outcome of this construction will likely determine whether Creekwood's product, which aims to be bioequivalent but may be formulated differently, literally infringes.