DCT

2:25-cv-03721

Axsome Malta Ltd v. Aurobindo Pharma USA Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-03721, D.N.J., 05/01/2025
  • Venue Allegations: Venue is alleged to be proper in the District of New Jersey because Defendant Aurobindo Pharma USA, Inc. maintains a regular and established place of business in the district, and because Defendant Aurobindo Pharma Limited is a foreign entity.
  • Core Dispute: Plaintiff alleges that Defendant’s submission of an Abbreviated New Drug Application (ANDA) to the FDA for a generic version of Plaintiff's Sunosi® (solriamfetol) drug product infringes a patent related to methods of administering the therapy to patients with impaired renal function.
  • Technical Context: The technology concerns pharmaceutical method-of-use claims for solriamfetol, a wakefulness-promoting agent, specifying particular dosing regimens for patients with varying degrees of kidney impairment to optimize safety and tolerability.
  • Key Procedural History: The lawsuit was initiated under the Hatch-Waxman Act following Plaintiff's receipt of a Paragraph IV Certification Notice Letter from Defendant, which alleged that the patent-in-suit is invalid and/or will not be infringed by the proposed generic product. The complaint notes this was the ninth such notice letter sent by the Defendant concerning a large family of patents related to the Sunosi® product.

Case Timeline

Date Event
2020-03-19 ’016 Patent Priority Date
2025-01-14 ’016 Patent Issue Date
2025-03-19 Defendant sent ninth Paragraph IV Certification Notice Letter regarding the ’016 Patent (no earlier than)
2025-05-01 Complaint Filing Date

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

U.S. Patent No. 12,194,016 - Methods of Providing Solriamfetol Therapy to Subjects with Impaired Renal Function

  • Patent Identification: U.S. Patent No. 12,194,016, “Methods of Providing Solriamfetol Therapy to Subjects with Impaired Renal Function,” issued January 14, 2025.

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of safely administering solriamfetol, a drug primarily eliminated by the kidneys, to patients with impaired renal function (’016 Patent, col. 2:40-51). Standard doses in these patients could lead to higher drug exposure and an increased risk of adverse effects such as headache, nausea, and anxiety, but it was previously unknown what specific dose or titration schedule would be safe and effective for this population (’016 Patent, col. 2:33-56).
  • The Patented Solution: The invention provides specific, tailored dosing regimens based on a patient’s measured level of renal impairment, or estimated glomerular filtration rate (eGFR) (’016 Patent, Abstract). For patients with moderate renal impairment, the patent discloses a dose escalation scheme that starts with a lower initial dose and requires a longer waiting period before increasing to a maximum dose, allowing the patient to develop tolerance and reducing the incidence of adverse effects (’016 Patent, col. 3:1-12). For patients with severe renal impairment, it provides for a reduced maximum daily dose (’016 Patent, col. 3:12-16).
  • Technical Importance: The claimed methods enable the safe therapeutic use of solriamfetol in a vulnerable patient population that might otherwise be unable to tolerate the drug due to kidney-related safety concerns (’016 Patent, col. 2:48-56).

Key Claims at a Glance

  • The complaint asserts infringement of at least independent claim 1 (’016 Patent, col. 50:15-24; Compl. ¶37).
  • The essential elements of independent claim 1 are:
    • A method of treating excessive daytime sleepiness in a human subject.
    • Selecting a subject and determining their eGFR.
    • Providing the subject, if they have an eGFR in the normal to mild impairment range (about 60 mL/min/1.73 m² or greater), a first oral daily dose equivalent to 75 mg of APC for 3 days.
    • Subsequently providing a second oral daily dose equivalent to 150 mg of APC for at least 3 days.
  • The complaint alleges infringement of "one or more claims" of the patent, thereby reserving the right to assert dependent claims as well (Compl. ¶37).

III. The Accused Instrumentality

Product Identification

  • The accused instrumentality is Defendant Aurobindo's proposed generic solriamfetol oral tablets, for which it submitted ANDA No. 218725 to the FDA for approval (Compl. ¶1).

Functionality and Market Context

  • The complaint alleges that Aurobindo's product is a generic version of Axsome's commercial product, Sunosi® (solriamfetol) oral tablets (Compl. ¶1). Sunosi® is a dopamine and norepinephrine reuptake inhibitor (DNRI) indicated to improve wakefulness in adult patients experiencing excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea (Compl. ¶9).
  • The act of infringement alleged in this case is the submission of the ANDA itself, which seeks FDA approval to market the generic product for the same therapeutic uses as Sunosi® prior to the expiration of the ’016 Patent (Compl. ¶¶1, 37).

IV. Analysis of Infringement Allegations

The complaint does not provide sufficient detail for a conventional claim-chart analysis. As is common in complaints filed quickly in response to a Paragraph IV notice, the infringement allegations are pleaded at a high level without quoting or referencing specific portions of the defendant's proposed product labeling submitted in the ANDA. The complaint alleges that Aurobindo's submission of its ANDA constitutes an act of infringement under 35 U.S.C. § 271(e)(2)(A) because the use for which the generic product will be labeled and marketed would infringe one or more claims of the ’016 patent, including at least claim 1 (Compl. ¶37).

The central theory of infringement in such a case is that the proposed product label will inevitably instruct or encourage physicians and patients to practice the patented method. For Aurobindo's product to infringe claim 1, its label would need to direct physicians to prescribe, for patients with normal-to-mild renal impairment, an initial 75 mg daily dose for three days, followed by an increase to a 150 mg daily dose. The litigation will focus on the precise instructions contained within the proposed label that Aurobindo submitted to the FDA.

No probative visual evidence provided in complaint.

  • Identified Points of Contention:
    • Scope Questions: A central question will be whether Aurobindo’s proposed product label instructs the specific dosing regimen of claim 1 for the specified patient population (normal to mild renal impairment). A defendant in such a case may attempt to avoid infringement by "carving out" the patented method from its label, and the dispute will center on whether any such carve-out is legally and factually sufficient.
    • Technical Questions: A key factual question for the court will be the comparison between the method steps recited in the asserted claims and the instructions for use contained in the proposed product labeling within Aurobindo's ANDA submission.

V. Key Claim Terms for Construction

  • The Term: "for 3 days"

  • Context and Importance: Claim 1 requires administering the initial 75 mg dose "for 3 days" before escalating to 150 mg (’016 Patent, col. 50:22-23). Practitioners may focus on this term because the patent's detailed description provides a different characterization for the recommended regimen in patients with mild renal impairment, stating the dose may be increased "after at least 3 days" (’016 Patent, col. 5:23-24). The potential difference between the claim's specific duration ("for 3 days") and the specification's more open-ended timing ("after at least 3 days") will be a critical point in determining the scope of the claim.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: A plaintiff may argue that an instruction to dose for "at least 3 days" necessarily includes the instruction to dose "for 3 days," and thus a label with the former language would induce infringement of a claim with the latter.
    • Evidence for a Narrower Interpretation: A defendant may argue that the patentee's choice of the specific phrase "for 3 days" in the claim, which differs from the "at least 3 days" language in the specification, represents a deliberate limitation of the claim scope to exactly three days, thereby disclaiming a broader interpretation.

  • The Term: "about 60 mL/min/1.73 m² to about 89 mL/min/1.73 m²"

  • Context and Importance: This term defines the eGFR range for patients with mild renal impairment covered by claim 1 (’016 Patent, col. 50:19-21). The interpretation of "about" will determine how much, if any, the claimed numerical range can be expanded. This is important if the accused product label specifies a slightly different, non-overlapping range for this patient category.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The term "about" is used, which inherently suggests the endpoints are not rigid and can encompass minor variations.
    • Evidence for a Narrower Interpretation: The patent specification directly links the claimed eGFR ranges to established FDA guidance for defining "Mild," "Moderate," and "Severe" renal impairment (’016 Patent, col. 13:4-14). A defendant may argue that "about" cannot be used to extend the claim beyond these standard, well-understood clinical definitions that the patentee appears to have adopted.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that upon FDA approval, Aurobindo will induce infringement under 35 U.S.C. § 271(b) by intentionally encouraging acts of direct infringement through its product labeling and marketing (Compl. ¶40). It also alleges contributory infringement under § 271(c), asserting that Aurobindo knows its product is designed for an infringing use and that the product lacks a substantial non-infringing use (Compl. ¶41).
  • Willful Infringement: The complaint does not contain an explicit allegation of willful infringement. However, it does request an award of attorneys' fees under 35 U.S.C. § 285, alleging that the case is "exceptional" (Compl. ¶44). This allegation is based on the same underlying conduct that could support willfulness but presents a different legal standard for recovery.

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

  • A core issue will be one of label scope: Does Aurobindo’s proposed product label, as submitted in its ANDA, contain instructions that direct physicians or patients to perform the specific dose-titration method recited in the asserted claims of the ’016 patent for the relevant patient population?
  • A dispositive legal question will be one of claim construction: Can the phrase "for 3 days" in claim 1 be construed to cover a dosing instruction of "for at least 3 days"? The court's interpretation of this temporal limitation may determine the outcome of the infringement analysis.