Shionogi Inc v. Zydus Pharma USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Shionogi Inc. (Delaware)
  • Defendant: Zydus Pharmaceuticals (USA) Inc. (New Jersey); Zydus Lifesciences Limited (India); Zydus Lifesciences Global FZE (United Arab Emirates)
  • Plaintiff's Counsel: FBT Gibbons LLP
• Case Identification: Shionogi Inc. v. Zydus Pharmaceuticals (USA) Inc., 2:26-cv-06619, D.N.J., 06/05/2026
• Venue Allegations: Venue is alleged to be proper in the District of New Jersey because Defendant Zydus USA has a regular and established place of business in the district, and the foreign defendants may be sued in any judicial district.
• Core Dispute: Plaintiff alleges that Defendants' submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of RADICAVA ORS® constitutes an act of infringement of three U.S. patents covering oral formulations of edaravone and methods of their administration.
• Technical Context: The technology relates to oral pharmaceutical compositions of edaravone for the treatment of Amyotrophic Lateral Sclerosis (ALS), specifically addressing how to administer the drug in relation to food consumption to ensure consistent and effective absorption.
• Key Procedural History: This action arises under the Hatch-Waxman Act, triggered by Defendants' submission of ANDA No. 220849 seeking to market a generic version of Plaintiff's drug, RADICAVA ORS®, prior to the expiration of patents listed in the FDA's Orange Book. The complaint notes that Plaintiff recently acquired the RADICAVA ORS® assets from Tanabe Pharma Corporation and that numerous related patent infringement actions against other generic manufacturers are pending in the same district.

Case Timeline

Date	Event
2020-11-12	Earliest Priority Date for '611, '769, and '469 Patents
2022-05-12	FDA Approval of RADICAVA ORS® (NDA No. 215446)
2022-08-05	Zydus USA submits FOIA request for RADICAVA ORS® approval summary
2024-03-28	FDA grants Orphan Drug Exclusivity for RADICAVA ORS®
2025-11-25	U.S. Patent No. 12,478,611 Issues
2025-12-22	Shionogi announces agreement to acquire RADICAVA ORS® business
2026-01-20	U.S. Patent No. 12,527,769 Issues
2026-03-10	U.S. Patent No. 12,569,469 Issues
2026-04-01	Shionogi completes acquisition of RADICAVA ORS® assets
2026-04-21	Date of Zydus's Notice Letter regarding ANDA No. 220849
2026-06-05	Complaint for Patent Infringement Filed
2029-05-12	RADICAVA ORS® Orphan Drug Exclusivity Expires

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

U.S. Patent No. 12,478,611

• Patent Identification: U.S. Patent No. 12,478,611, "Pharmaceutical composition for oral administration of edaravone and method of administering same," issued November 25, 2025.

The Invention Explained

• Problem Addressed: The patent addresses the challenge that the oral absorption of edaravone, an active ingredient for treating ALS, is significantly affected by food consumption (the "food effect") ´611 Patent, col. 3:8-13 Prior to this invention, edaravone was only available as an injectable agent, which is burdensome for ALS patients ´611 Patent, col. 1:56-61
• The Patented Solution: The patent discloses a method for administering an oral edaravone composition by specifying distinct time intervals between meal consumption and drug administration, tailored to the type of meal (high-fat, standard, or light) ´611 Patent, abstract This method is designed to avoid the food effect and achieve a pharmacokinetic (PK) profile (i.e., Cmax and AUC) comparable to that achieved under fasting conditions, thereby ensuring consistent drug efficacy ´611 Patent, col. 2:1-22
• Technical Importance: This method provides a predictable dosing regimen that enables the convenient oral administration of edaravone, improving the quality of life for ALS patients by replacing burdensome intravenous infusions while maintaining therapeutic consistency.

Key Claims at a Glance

• The complaint asserts at least Independent Claim 1 Compl. ¶49
• Independent Claim 1 of the '611 patent is a method claim for treating amyotrophic lateral sclerosis, which includes the following essential elements:
  • Orally or intragastrically administering a liquid pharmaceutical composition comprising edaravone at a dose of 90 to 120 mg.
  • Administering with a "first time interval" from the consumption of a meal to the drug administration.
  • The interval is specified based on meal type: 8 hours for a high-fat meal (800-1000 calories, 50% fat), 4 hours for a standard meal (400-500 calories, 25% fat), and 2 hours for a light meal (250 calories).
  • This administration protocol "achieves the same pharmacokinetics as administration... under a fasting condition of 10 hours or longer," where "the same pharmacokinetics includes Cmax and AUC."

U.S. Patent No. 12,527,769

• Patent Identification: U.S. Patent No. 12,527,769, "Pharmaceutical composition for oral administration of edaravone and method of administering same," issued January 20, 2026.

The Invention Explained

• Problem Addressed: Like the '611 patent, the '769 patent addresses the negative impact of food on the oral absorption and bioavailability of edaravone, which can lead to sub-therapeutic drug levels if not properly managed ´769 Patent, col. 16:39-44
• The Patented Solution: The patent claims a method of administering a specific formulation-a liquid suspension of edaravone-using timed intervals relative to meals ´769 Patent, claim 1 The claim defines the successful outcome of this method with explicit functional language: the administration results in a decrease in maximum concentration (Cmax) of less than 20% and/or a decrease in total drug exposure (AUC) of less than 10% compared to administration in a fasted state ´769 Patent, claim 1
• Technical Importance: By claiming a method tied to a specific formulation type (suspension) and defined by a specific, quantifiable PK outcome, the patent provides a durable and enforceable solution to making oral edaravone a viable therapeutic alternative to IV administration.

Key Claims at a Glance

• The complaint asserts at least Independent Claim 1 Compl. ¶60
• Independent Claim 1 of the '769 patent is a method claim for treating amyotrophic lateral sclerosis, which includes the following essential elements:
  • Orally or intragastrically administering a liquid pharmaceutical composition that is a suspension comprising edaravone.
  • The administration occurs after a specific time interval following a meal: 8 hours for a high-fat meal, 4 hours for a low-fat meal, or 2 hours for a caloric supplement.
  • The method results in a specific pharmacokinetic outcome: "a decrease in Cmax is less than 20% with respect to Cmax in a same time range in fasting for 10 hours or longer and/or that a decrease in AUC is less than 10% with respect to AUC in a same time range in fasting for 10 hours or longer."

U.S. Patent No. 12,569,469

• Patent Identification: U.S. Patent No. 12,569,469, "Pharmaceutical composition for oral administration of edaravone and method of administering same," issued March 10, 2026.

Technology Synopsis

The '469 patent addresses the food effect on oral edaravone by claiming a method of administration that specifies a "first time interval" between a meal and drug intake, as well as a "second time interval" between drug intake and the next meal ´469 Patent, claim 2 This two-part timing regimen is designed to ensure consistent drug absorption similar to fasting conditions for a liquid pharmaceutical composition used to treat ALS ´469 Patent, claim 1

Asserted Claims

The complaint asserts at least Independent Claim 1 Compl. ¶71

Accused Features

The accused features are Defendants' proposed generic edaravone oral suspension and its associated product labeling, which are alleged to instruct or encourage administration in a manner that would perform the claimed method Compl. ¶72

III. The Accused Instrumentality

Product Identification

• Defendants' proposed edaravone oral suspension, which is the subject of ANDA No. 220849 submitted to the FDA (Compl. ¶¶2; Compl. ¶20).

Functionality and Market Context

• The accused product is a liquid oral suspension of edaravone with a proposed concentration of 105 mg/5 mL Compl. ¶42 It is intended to be a generic equivalent to Plaintiff's RADICAVA ORS®, which is an approved treatment for ALS that improves upon the prior, burdensome intravenous formulation Compl. ¶¶11-12 Compl. ¶43 The complaint alleges that upon approval, Defendants will manufacture and sell this product for the same therapeutic use, thereby competing directly with RADICAVA ORS® (Compl. ¶¶22; Compl. ¶27).

IV. Analysis of Infringement Allegations

The complaint alleges infringement under 35 U.S.C. § 271(e)(2), where the filing of an ANDA for a generic version of a patented drug is a statutory act of infringement. The infringement theory is that the administration of Defendants' proposed generic product, in accordance with its proposed labeling, will directly infringe the asserted method claims.

No probative visual evidence provided in complaint.

'611 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method of treating amyotrophic lateral sclerosis, comprising: orally or intragastrically administering, to a subject in need thereof, a liquid pharmaceutical composition comprising edaravone...	Defendants' ANDA product is a liquid oral suspension of edaravone intended for treating ALS.	¶42; ¶44	col. 11:15-18
...with a first time interval from a consumption of a meal by the subject in need thereof to an administration of the liquid pharmaceutical composition...	The proposed product labeling is alleged to instruct or encourage administration with specific time intervals relative to meals.	¶50	col. 2:2-9
...the first time interval for the consumption of a high-fat meal... is 8 hours... the first time interval for the consumption of a standard meal... is 4 hours... and the first time interval for the consumption of a light meal... is 2 hours...	The proposed labeling is alleged to instruct these specific meal-dependent timing protocols, thereby inducing infringement by users.	¶50	col. 7:46-8:65
...a dose of edaravone per administration is in a range of 90 to 120 mg...	The proposed product has a dose concentration of 105 mg/5 mL, which falls within the claimed dosage range.	¶42	col. 12:59-65
...such that the first time interval achieves the same pharmacokinetics as administration of the liquid pharmaceutical composition by the same method to the subject under a fasting condition of 10 hours or longer...	As a generic equivalent seeking approval based on the RLD's data, Defendants' product must be bioequivalent, and is therefore alleged to achieve the same PK profile as the patented method.	¶49	col. 6:1-20

'769 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method of treating amyotrophic lateral sclerosis, comprising: orally or intragastrically administering, to a subject in need thereof, a liquid pharmaceutical composition comprising edaravone... wherein the liquid pharmaceutical composition is a suspension...	Defendants' ANDA product is identified as a proposed "edaravone suspension."	¶42	col. 5:7-10
...with a first time interval for the consumption of a high-fat meal... is 8 hours..., the first time interval for the consumption of a low-fat meal... is 4 hours..., or the first time interval for the consumption of a caloric supplement... is 2 hours...	The proposed product labeling is alleged to instruct or encourage administration using these specific meal-dependent time intervals.	¶61	col. 17:1-6
...such that a decrease in Cmax is less than 20% with respect to Cmax in a same time range in fasting for 10 hours or longer and/or that a decrease in AUC is less than 10% with respect to AUC in a same time range in fasting for 10 hours or longer.	Because the accused product must be bioequivalent to RADICAVA ORS® to gain FDA approval, it is alleged that it will necessarily exhibit the claimed pharmacokinetic outcomes, which are based on the clinical studies for RADICAVA ORS®.	¶60	col. 15:45-18:44; Table 3

• Identified Points of Contention:
  • Scope Questions: A central dispute may arise over the definitions of "high-fat meal," "standard meal," and "light meal." The patents provide specific caloric and fat-percentage definitions ´611 Patent, col. 7:37-8:15 The infringement analysis will depend on whether the proposed label for the generic product uses language that falls squarely within these definitions.
  • Technical Questions: For the '611 patent, a question is whether "the same pharmacokinetics" requires literal identity or if it can be satisfied by meeting regulatory standards for bioequivalence. For the '769 patent, a key question will be whether Defendants' product, even if bioequivalent, can be proven to meet the specific percentage-based Cmax and AUC limitations recited in the claim across all patient populations and meal conditions.

V. Key Claim Terms for Construction

• The Term: "achieves the same pharmacokinetics" (from '611 Patent, Claim 1)

• Context and Importance: This functional limitation is the core of Claim 1 of the '611 patent. Its definition will determine the standard of proof for infringement. Practitioners may focus on this term because its interpretation-whether it means regulatory bioequivalence or something stricter-could decide the outcome of the infringement analysis.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification suggests a bioequivalence standard, stating that "'the same pharmacokinetics' means... statistically the same level to common criteria for bioequivalence (e.g., a least squares mean ratio and its 90% confidence interval are in the range of 0.8 to 1.25)" ´611 Patent, col. 6:10-20 This supports interpreting the term through the lens of established regulatory standards.
  • Evidence for a Narrower Interpretation: A defendant may argue that the plain meaning of "the same" requires a higher degree of similarity than the flexible 80-125% bioequivalence range. They might also point to the specific mean values in the patent's clinical study data ´611 Patent, Table 2; FIG. 1 as the standard for what "the same" PK profile entails, arguing for a narrower, data-driven interpretation.

• The Term: "suspension" (from '769 Patent, Claim 1)

• Context and Importance: This term narrows the asserted claim to a specific type of formulation. Infringement requires that the accused product be a "suspension." Practitioners may focus on this term to see if any formulation differences in the accused product could be leveraged for a non-infringement argument.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification describes suspensions in general terms, including "edaravone particles, a dispersing agent and water" ´769 Patent, col. 5:7-9 This broad description could encompass any formulation where edaravone is not fully dissolved.
  • Evidence for a Narrower Interpretation: The patent provides a highly detailed example of a preferred suspension, including specific excipients like polyvinyl alcohol as a dispersing agent and xanthan gum as a thickening agent ´769 Patent, col. 15:1-17 A defendant could argue that a "suspension" within the meaning of the patent requires specific functional properties (e.g., stability, redispersibility) taught in connection with these exemplary excipients, and a formulation lacking them is not what was claimed.

VI. Other Allegations

• Indirect Infringement: The complaint alleges active inducement of infringement under 35 U.S.C. § 271(b). The factual basis is that Defendants' proposed product labeling will allegedly instruct and encourage physicians, pharmacists, and patients to administer the generic product according to the patented methods (Compl. ¶¶50; Compl. ¶61; Compl. ¶72).
• Willful Infringement: The complaint alleges willful infringement based on Defendants' knowledge of the patents-in-suit. It is alleged that Defendants were aware of the patents prior to amending their ANDA to include a Paragraph IV certification and proceeded with their application despite an "objectively high likelihood" of infringement (Compl. ¶¶54; Compl. ¶65; Compl. ¶76). This alleges pre-suit knowledge and a deliberate disregard for Plaintiff's patent rights.

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

1. A core issue will be one of definitional scope: can the functional claim language, such as "achieves the same pharmacokinetics" in the '611 patent and the specific PK percentage decreases in the '769 patent, be met by simply showing regulatory bioequivalence, or will the court require a stricter, more literal proof of identity tied to the patent's specific examples?

2. A second central question will relate to induced infringement: will the language in Defendants' proposed product label be found to provide a clear "instruction" or "encouragement" to perform the patented methods, or will it be deemed sufficiently ambiguous or different from the patents' specific meal-and-timing recitations to allow for non-infringing uses?

3. An underlying evidentiary battle will likely focus on bioequivalence versus claimed function: does the fact that Defendants' product is intended to be bioequivalent to RADICAVA ORS® automatically mean it infringes the functional limitations of the patents, or can Defendants introduce evidence that its specific formulation, while bioequivalent overall, does not meet the precise Cmax and AUC parameters required by the claims under all specified meal conditions?