DCT

2:24-cv-10619

Axsome Malta Ltd v. Aurobindo Pharma USA Inc

Log In

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:24-cv-10619, D.N.J., 11/20/2024
  • Venue Allegations: Venue is based on Defendant Aurobindo Pharma USA, Inc.’s principal place of business in the District of New Jersey and on Aurobindo Pharma Limited’s alleged systematic contacts and business activities within the district, conducted directly or through its U.S. subsidiary.
  • Core Dispute: Plaintiff alleges that Defendant’s Abbreviated New Drug Application (ANDA) to market a generic version of Plaintiff's Sunosi® (solriamfetol) tablets constitutes an act of infringement of a patent covering methods for administering the drug to lactating women.
  • Technical Context: The technology concerns a pharmaceutical method of use designed to minimize an infant's exposure to the drug solriamfetol, a treatment for excessive daytime sleepiness, when a lactating mother undergoes therapy.
  • Key Procedural History: This action was filed under the Hatch-Waxman Act, triggered by Aurobindo's submission of ANDA No. 218725 and a corresponding Paragraph IV certification. The complaint notes that Aurobindo sent its seventh notice letter regarding this ANDA on October 8, 2024, which for the first time included a challenge to the patent-in-suit. The complaint also references a related, consolidated litigation against other generic manufacturers concerning the same drug product.

Case Timeline

Date Event
2022-12-30 U.S. Patent No. 12,090,126 Priority Date
2023-08-10 Aurobindo sends First Paragraph IV Notice Letter to Axsome
2023-12-08 Aurobindo sends Second Paragraph IV Notice Letter to Axsome
2024-02-13 Aurobindo sends Third Paragraph IV Notice Letter to Axsome
2024-02-27 Aurobindo sends Fourth Paragraph IV Notice Letter to Axsome
2024-05-21 Aurobindo sends Fifth Paragraph IV Notice Letter to Axsome
2024-07-09 Aurobindo sends Sixth Paragraph IV Notice Letter to Axsome
2024-09-17 U.S. Patent No. 12,090,126 Issues
2024-10-08 Aurobindo sends Seventh Paragraph IV Notice Letter to Axsome (addressing '126 patent)
2024-11-20 Complaint Filed

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

U.S. Patent No. 12,090,126 - Methods of Administering Solriamfetol to Lactating Women

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of administering solriamfetol, a drug used to treat excessive daytime sleepiness, to lactating mothers (’126 Patent, col. 1:15-20). A key concern is that the drug is excreted into breast milk, potentially at concentrations higher than in the mother's plasma, which could cause adverse events in a nursing infant (’126 Patent, col. 7:22-29).
  • The Patented Solution: The patent discloses a method to reduce an infant's exposure to the drug by coordinating the timing of drug administration and breastfeeding. The method involves administering a dose of solriamfetol and then waiting a specified period—for example, at least 3.5 or 5 hours—before feeding the infant breast milk (’126 Patent, col. 2:20-28; col. 2:57-65). This delay is designed to allow the concentration of solriamfetol in the breast milk to decrease after reaching its peak, as illustrated in the patent's Figure 1, which plots the drug's concentration over time in both plasma and breast milk (’126 Patent, col. 3:26-30).
  • Technical Importance: This pharmacokinetic-based timing strategy provides a protocol for lactating women with conditions like narcolepsy to use an effective therapy while mitigating the risk of drug exposure to their infants, a significant consideration in clinical practice (’126 Patent, col. 14:42-49).

Key Claims at a Glance

  • The complaint asserts infringement of at least independent claim 1 ('Compl. ¶35).
  • The essential elements of independent claim 1 are:
    • A method for treating excessive daytime sleepiness (EDS) in a lactating human mother who wishes to breastfeed.
    • First, determining the mother’s Epworth Sleepiness Scale (ESS) score and whether she experiences sleep attacks.
    • Second, if the mother has an ESS score of 15 or greater and experiences sleep attacks, providing a specific starting dose and titration schedule for solriamfetol, which differs depending on whether the EDS is associated with obstructive sleep apnea or narcolepsy.
    • Third, feeding the infant breast milk obtained at least about 3.5 hours after drug administration.
    • The claim further recites that the median Tmax (time to peak concentration) in breast milk is approximately 1.1 hours and specifies the resulting daily infant dose levels.
  • The complaint alleges infringement of "one or more claims," which may include dependent claims not specifically identified (Compl. ¶35).

III. The Accused Instrumentality

Product Identification

Aurobindo’s proposed generic solriamfetol oral tablets, for which it seeks FDA approval via ANDA No. 218725 (Compl. ¶1, ¶24).

Functionality and Market Context

The accused product is a generic equivalent of Sunosi®, a dopamine and norepinephrine reuptake inhibitor (DNRI) indicated for improving wakefulness in adult patients with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea (Compl. ¶2, ¶9). The complaint alleges that Aurobindo intends to manufacture and sell its generic product in the U.S. before the expiration of the ’126 Patent, thereby creating a justiciable controversy under the Hatch-Waxman Act (Compl. ¶25, ¶36).

IV. Analysis of Infringement Allegations

The complaint alleges that Aurobindo’s submission of its ANDA is an act of infringement under 35 U.S.C. § 271(e)(2)(A) because the use of Aurobindo's proposed product as directed by its proposed labeling will infringe at least Claim 1 of the ’126 Patent (Compl. ¶35). The complaint does not include a copy of the proposed label or provide a claim chart mapping specific label instructions to the elements of the asserted claim. The infringement theory relies on the premise that upon approval, the instructions for use accompanying Aurobindo's product will lead physicians and patients to practice the patented method (Compl. ¶¶ 37-39). No probative visual evidence provided in complaint.

The complaint does not provide sufficient detail for analysis of how each claim limitation is allegedly met.

  • Identified Points of Contention:
    • Label-Based Infringement: A central dispute will be whether the language of Aurobindo's proposed product label is sufficient to induce infringement of the entire multi-step method of Claim 1. The analysis will question whether the label instructs or merely describes the specific diagnostic step (determining ESS score and sleep attacks), the precise dosing and titration schedule, and the explicit feeding delay.
    • Scope Questions: Claim 1 contains highly specific limitations, such as the ESS score threshold ("15 or greater") and the waiting period ("at least about 3.5 hours"). The case may turn on whether the use of Aurobindo's product, as directed by its label, will necessarily result in each of these limitations being met for the relevant patient population.

V. Key Claim Terms for Construction

  • The Term: "determining the Epworth Sleepiness Scale (ESS) total score of the mother and if the mother experiences sleep attacks while caring for the infant" (from Claim 1(a)).

  • Context and Importance: This limitation defines a prerequisite diagnostic step. The infringement analysis depends on whether this step is performed by prescribers as a result of the generic label's instructions. Practitioners may focus on this term because its interpretation will define the evidentiary burden for proving direct infringement; a narrow construction could require proof of a formal, documented ESS assessment for every instance of infringement.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The patent specification describes the ESS as a "subjective sleepiness test that is well known in the art," which might support an argument that "determining" encompasses a physician's standard clinical evaluation of sleepiness, not necessarily a formal, scored test (’126 Patent, col. 15:10-12).
    • Evidence for a Narrower Interpretation: The subsequent limitation in Claim 1(b) requires an "ESS total score of 15 or greater," which suggests that a specific, quantitative "determination" is required, rather than a general clinical impression. This could support an argument that the claim requires a formal, scored assessment.

  • The Term: "at least about 3.5 hours" (from Claim 1(c)).

  • Context and Importance: This term is critical as it defines the core timing element of the invention. The scope of "about" will dictate the range of feeding delays that constitute infringement.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The specification frequently uses flexible language when discussing the waiting period, such as "at least about 2 hours (e.g., at least about 3, 4, or 5 hours)," suggesting the patentee did not intend to be limited to a precise number (’126 Patent, col. 1:56-59).
    • Evidence for a Narrower Interpretation: The claim links the 3.5-hour period to the technical goals of "avoiding exposing the infant to the maximum concentrations" and achieving a specific infant dose, given a Tmax of "approximately 1.1 hours" (’126 Patent, col. 32:5-18). A party could argue that "about 3.5 hours" must be construed narrowly in light of this stated scientific rationale.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that upon approval, Aurobindo will induce infringement by intentionally encouraging direct infringement through its product labeling, with knowledge of the ’126 Patent (Compl. ¶38). It also alleges contributory infringement, asserting that the proposed product is designed for an infringing use and lacks substantial non-infringing uses (Compl. ¶39). The existence of substantial non-infringing uses (e.g., by non-lactating patients) will likely be a significant point of dispute.
  • Willful Infringement: The complaint alleges the case is "exceptional" and seeks attorneys' fees under 35 U.S.C. § 285 (Compl. ¶42). This allegation is supported by Aurobindo's knowledge of the ’126 Patent, evidenced by its Paragraph IV certification and notice letter sent to Axsome prior to the suit (Compl. ¶33).

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

  • A core issue will be one of induced infringement: Given the highly detailed, multi-step nature of the asserted method claim, can Axsome demonstrate that Aurobindo’s proposed product label will actively encourage or instruct physicians and patients to perform every specific step, from the initial diagnostic screening to the precise, pharmacokinetically-timed feeding schedule?
  • A key evidentiary question will be one of label interpretation: Will the court find that Aurobindo’s proposed instructions for use inevitably lead to the practice of the patented method in lactating mothers, or will it find that the label is merely descriptive of the drug's properties, leaving physicians to exercise their own judgment in a way that may not always align with the claimed method?
  • The viability of the contributory infringement claim will be a central battleground: Can Axsome successfully argue that, for the specific sub-population of lactating mothers, Aurobindo's product lacks a substantial non-infringing use, or will Aurobindo prevail by arguing that the product's primary use is in the general population, where the method patent is irrelevant?