DCT
1:25-cv-00879
Supernus Pharma Inc v. MSN Pharma Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Supernus Pharmaceuticals, Inc. (Delaware)
- Defendant: MSN Pharmaceuticals Inc. (Delaware)
- Plaintiff’s Counsel: Faegre Drinker Biddle & Reath LLP
- Case Identification: 1:25-cv-00879, D. Del., 07/15/2025
- Venue Allegations: Venue is based on Defendant being a Delaware corporation and conducting business within the state.
- Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (ANDA) to the FDA for generic viloxazine extended-release capsules constitutes an act of infringement of six patents covering formulations and methods of using the drug to treat Attention Deficit Hyperactivity Disorder (ADHD).
- Technical Context: The technology concerns pharmaceutical formulations of viloxazine, a selective norepinephrine reuptake inhibitor, designed to provide extended release for once- or twice-daily dosing in the treatment of ADHD.
- Key Procedural History: This case was initiated under the Hatch-Waxman Act following Defendant’s Paragraph IV certification notice to Plaintiff. The complaint discloses that Plaintiff previously filed a suit in the District of New Jersey based on the same patents and ANDA; this Delaware action is presented as a protective suit to ensure statutory and regulatory deadlines are met pending resolution of any venue or jurisdictional disputes in the New Jersey action.
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 |
| 2025-06-05 | Defendant sends Paragraph IV Notice Letter to Plaintiff |
| 2025-07-11 | Plaintiff files prior action in the District of New Jersey |
| 2025-07-15 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,358,204 - "Formulations of Viloxazine"
- Patent Identification: U.S. Patent No. 9,358,204, "Formulations of Viloxazine," Issued June 7, 2016.
The Invention Explained
- Problem Addressed: The patent’s background section notes that viloxazine presents challenges for developing an extended-release formulation due to its potentially high therapeutic dose, weakly basic nature, and relatively high in vivo clearance rate in humans (’204 Patent, col. 1:41-45).
- The Patented Solution: The invention addresses this by creating a multi-component formulation that combines different release profiles. Specifically, the formulation includes an immediate release (IR) component for rapid onset and an extended release (XR) component to maintain the drug’s therapeutic effect over a longer period, enabling once- or twice-daily dosing (’204 Patent, col. 2:1-4; col. 7:47-53). The XR component is described as a multi-layered particle with a drug layer and a release-controlling outer layer (’204 Patent, col. 7:34-45).
- Technical Importance: This approach seeks to improve patient compliance and therapeutic outcomes by reducing the dosing frequency from the multiple daily doses required by typical immediate-release versions (’204 Patent, col. 3:12-16).
Key Claims at a Glance
The complaint alleges infringement of "one or more claims" without specifying them (Compl. ¶56). Independent claim 1 is representative of the formulation technology.
- Independent Claim 1:
- A pharmaceutical formulation comprising:
- (a) an immediate release (IR) component comprising an inert core and a layer of viloxazine; 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 (19:1 to 8.5:1.5).
- The formulation must contain 25% to 75% (w/w) viloxazine and release at least 80% of the drug over a period of at least 2 hours in vitro.
U.S. Patent No. 9,603,853 - "Formulations of Viloxazine"
- Patent Identification: U.S. Patent No. 9,603,853, "Formulations of Viloxazine," Issued March 28, 2017.
The Invention Explained
- Problem Addressed: The ’853 Patent addresses the same technical challenges as the ’204 Patent: the difficulty of creating a viable extended-release formulation for viloxazine due to its physicochemical and pharmacokinetic properties (’853 Patent, col. 1:41-45).
- The Patented Solution: The invention is an extended-release (XR) pharmaceutical formulation structured as a multi-layered particle. This particle consists of an inert core, a first layer containing viloxazine, and a second, outer layer containing a specific combination of a release rate controlling compound and a pore former designed to modulate the drug's dissolution over time (’853 Patent, col. 2:1-4; col. 7:34-45). Unlike the ’204 Patent’s claim 1, this patent’s independent claim 1 does not require the presence of a separate immediate-release component.
- Technical Importance: This technology provides a flexible platform for creating various extended-release profiles for viloxazine, which can be used alone or in combination with other components to fine-tune therapeutic delivery (’853 Patent, col. 3:39-45).
Key Claims at a Glance
The complaint alleges infringement of "one or more claims" (Compl. ¶75). Independent claim 1 is representative.
- Independent Claim 1:
- A pharmaceutical formulation comprising an extended release (XR) component.
- The XR component includes 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 (19:1 to 8.5:1.5).
- The formulation must contain 25% to 75% (w/w) viloxazine and release at least 80% of the drug over a period of at least 2 hours in vitro.
U.S. Patent No. 9,662,338 - "Formulations of Viloxazine"
- Patent Identification: U.S. Patent No. 9,662,338, "Formulations of Viloxazine," Issued May 30, 2017.
- Technology Synopsis: This patent, like the ’204 and ’853 patents, is directed to modified-release pharmaceutical formulations of viloxazine. It claims formulations comprising an extended-release component with specific structural layers and compositions designed to control the drug's release rate over time (’338 Patent, col. 27:26-57).
- Asserted Claims: The complaint asserts infringement of one or more unspecified claims (Compl. ¶94). Independent Claim 1 is representative.
- Accused Features: The accused features are Defendant's generic viloxazine extended-release capsules, which are alleged to embody the claimed formulation technology (Compl. ¶¶40, 88).
U.S. Patent No. 11,324,753 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
- Patent Identification: U.S. Patent No. 11,324,753, "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued May 10, 2022.
- Technology Synopsis: This patent is directed to a method of treating ADHD. The invention is based on the discovery that viloxazine exhibits antagonist activity at both the 5-HT7 and 5HT1B serotonin receptors, and it claims a method of treating ADHD by administering viloxazine to achieve this dual antagonism (’753 Patent, col. 1:29-32, 46-51).
- Asserted Claims: The complaint asserts infringement of one or more unspecified claims (Compl. ¶113). Independent Claim 1 is representative.
- Accused Features: Infringement is alleged based on the proposed labeling for Defendant’s ANDA Products, which indicates the drug for treating ADHD and describes its pharmacodynamic effects on serotonin receptors, thereby allegedly inducing physicians and patients to practice the claimed method (Compl. ¶¶44, 47, 116).
U.S. Patent No. 11,458,143 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
- Patent Identification: U.S. Patent No. 11,458,143, "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued October 4, 2022.
- Technology Synopsis: This patent claims a method of treating ADHD by administering a therapeutically effective amount of viloxazine in a formulation. The claims cover specific daily dosage amounts and are not tied to the specific receptor antagonism mechanism claimed in the ’753 patent (’143 Patent, col. 8:1-7).
- Asserted Claims: The complaint asserts infringement of one or more unspecified claims (Compl. ¶132). Independent Claim 1 is representative.
- Accused Features: The accused features are the proposed labeling for Defendant’s ANDA Products, which allegedly instructs for the administration of viloxazine for ADHD according to the dosages and schedules claimed in the patent (Compl. ¶¶44, 45, 135).
U.S. Patent No. 12,121,523 - "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)"
- Patent Identification: U.S. Patent No. 12,121,523, "Method of Treatment of Attention Deficit/Hyperactivity Disorder (ADHD)," Issued October 22, 2024.
- Technology Synopsis: This patent is directed to methods of treating mood or affective disorders (such as anxiety or depression) that are co-morbid with ADHD. The method consists of administering a therapeutically effective amount of viloxazine to a patient diagnosed with such co-morbid conditions (’523 Patent, col. 11:24-34).
- Asserted Claims: The complaint asserts infringement of one or more unspecified claims (Compl. ¶151). Independent Claim 1 is representative.
- Accused Features: The accused features are the proposed labeling for Defendant’s ANDA Products, which indicates the product for ADHD and includes warnings related to depression and anxiety, allegedly encouraging its use in patients with these co-morbid disorders (Compl. ¶¶44, 48, 154).
III. The Accused Instrumentality
- Product Identification: Defendant’s Abbreviated New Drug Application No. 220551 for generic viloxazine extended-release capsules in 100 mg, 150 mg, and 200 mg strengths ("Defendant's ANDA Products") (Compl. ¶7).
- Functionality and Market Context:
- The complaint alleges Defendant’s ANDA Products are generic versions of, and bioequivalent to, Plaintiff’s approved drug, Qelbree® (viloxazine extended-release capsules) (Compl. ¶¶39, 41).
- The proposed prescribing information for the ANDA Products is alleged to be substantially the same as the approved labeling for Qelbree® (Compl. ¶43). This labeling allegedly indicates the product for the "treatment of Attention-Deficit Hyperactivity Disorder (ADHD) in adults and pediatric patients 6 years and older" (Compl. ¶44).
- The proposed label is also alleged to contain sections on "Dosage and Administration," "Mechanism of Action," and "Pharmacodynamics" that describe the recommended dosing regimens and the drug's known and theoretical biological activities, including inhibiting the reuptake of norepinephrine and binding to certain serotonin receptors (Compl. ¶¶45-47).
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: (a) an immediate release (IR) component... and (b) an extended release (XR) component... | Defendant's ANDA Products are alleged to be extended-release capsules containing viloxazine that are bioequivalent to Qelbree®, which is alleged to be a multi-component formulation. | ¶¶40, 41 | col. 7:34-45 |
| wherein the formulation comprises, as a percentage of the total formulation, 25% (w/w) to 75% (w/w) viloxazine | Defendant's ANDA Products are viloxazine capsules alleged to meet the claimed formulation parameters. | ¶40 | col. 8:12-14 |
| wherein the viloxazine is released immediately and continuously upon administration | Defendant’s ANDA Products are extended-release capsules alleged to have a release profile meeting the claim limitations. | ¶40 | col. 8:15-17 |
- Identified Points of Contention:
- Technical Questions: A primary question will be evidentiary. As the complaint lacks specific details about the ANDA Product's composition—noting Plaintiff has not yet received a copy of the ANDA (Compl. ¶19)—the central dispute will be whether the accused product's formulation actually contains the distinct IR and XR multi-layered particle structures with the specific component ratios required by Claim 1.
'853 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A pharmaceutical formulation, comprising 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... | Defendant's ANDA Products are alleged to be extended-release capsules containing viloxazine, which are alleged to embody the claimed multi-layered particle structure. | ¶¶40, 41 | col. 27:32-47 |
| wherein the formulation comprises... 25% (w/w) to 75% (w/w) viloxazine | Defendant's ANDA Products are viloxazine capsules alleged to meet the claimed formulation parameters. | ¶40 | col. 27:54-56 |
| wherein at least 80% of the viloxazine... is released from the formulation over a period of time of at least 2 hours in vitro. | Defendant’s ANDA Products are extended-release capsules alleged to have a release profile that meets the claim limitations. | ¶40 | col. 27:58-61 |
- Identified Points of Contention:
- Technical Questions: Similar to the '204 patent, the core issue will be factual and dependent on the undisclosed details of the ANDA filing. The question for the court will be whether the accused product contains the specific multi-layered XR component structure and composition claimed, particularly the presence of an inert core, distinct layers, and specified types of release-controlling compounds and pore formers.
V. Key Claim Terms for Construction
For the Formulation Patents (’204, ’853, ’338)
- The Term: "release rate controlling compound"
- Context and Importance: This term defines the essential functional ingredient in the outer layer of the claimed XR component. The infringement analysis for the formulation patents will depend on whether the excipients used in Defendant's product fall within the scope of this term. Practitioners may focus on this term because the specific class and amount of polymer used to control drug release is a common point of design difference between branded and generic formulations.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides a list of exemplary compounds, stating they "include" ethyl cellulose, various waxes, and specific polymers like Eudragit (’853 Patent, col. 28:44-53). The use of "include" suggests the list is not exhaustive.
- Evidence for a Narrower Interpretation: A defendant might argue the term should be limited to the specific classes of hydrophobic compounds disclosed in the examples and preferred embodiments, potentially excluding other types of extended-release agents not explicitly mentioned (’853 Patent, col. 2:42-53).
For the Method of Use Patents (’753, ’143, ’523)
- The Term: "therapeutically effective amount" (appearing in claims of the method patents, e.g., ’753 Patent, Claim 1)
- Context and Importance: The definition of what constitutes a "therapeutically effective amount" for treating ADHD is central to the method claims. Infringement will require showing that the dosage instructions on the accused product's label direct the administration of an amount that is effective for ADHD.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides a wide range of potential daily doses, from "10 to 600 mg/day" and suggests pediatric dosages from "1.1 mg/kg/day to 9.7 mg/kg/day" (’753 Patent, col. 6:14-19). This supports a broad definition covering the dosages on the accused label (Compl. ¶45).
- Evidence for a Narrower Interpretation: The specification also discusses dosages in the context of providing an "improved adverse effect profile" compared to those used for depression (’753 Patent, col. 6:28-43). A defendant could argue that "therapeutically effective amount" must be construed to mean an amount that not only treats ADHD but also provides this improved safety profile, a feature the accused label may not explicitly teach.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents. For the formulation patents, inducement is based on distributing the product with labeling that describes its infringing composition (Compl. ¶¶61, 99). For the method patents, inducement is based on the proposed labeling, which allegedly instructs physicians and patients on how to use the drug in an infringing manner for the treatment of ADHD (Compl. ¶¶78, 116, 135, 154).
- Willful Infringement: Willfulness is alleged for all six patents. The basis for these allegations is Defendant's alleged knowledge of the patents-in-suit, as evidenced by its filing of a Paragraph IV certification that specifically identified each patent, and its continued intent to market the accused products prior to patent expiration (Compl. ¶¶64, 83, 102, 121, 140, 159).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of structural identity: Does the defendant's generic formulation, as confidentially described in its ANDA, contain the specific multi-component, layered particle structures and excipient ratios required by the claims of the formulation patents (’204, ’853, ’338)? Resolution of this question will depend entirely on technical evidence not yet public.
- A key legal question will be one of induced infringement: Does the language in the defendant's proposed label, which is expected to substantially copy the brand-name label, meet the legal standard for actively encouraging infringement of the method-of-use claims—particularly the claim in the ’753 patent requiring the specific biological mechanism of "antagonizing" 5-HT7 and 5HT1B receptors?
- A procedural question of judicial economy is also present: Given the parallel actions filed in the District of New Jersey and the District of Delaware, the initial phase of litigation may focus on determining the proper forum for the dispute before the substantive patent questions are addressed (Compl. ¶163).