Axsome Malta Ltd v. Aurobindo Pharma USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Axsome Malta Ltd. (Malta) and Axsome Therapeutics, Inc. (Delaware)
  • Defendant: Aurobindo Pharma USA, Inc. (Delaware) and Aurobindo Pharma Limited (India)
  • Plaintiff’s Counsel: Saul Ewing LLP
• Case Identification: 2:25-cv-17592, D.N.J., 11/14/2025
• Venue Allegations: Venue is alleged in the District of New Jersey based on Defendant Aurobindo Pharma USA, Inc. maintaining a regular and established place of business within the district. For Defendant Aurobindo Pharma Limited, a foreign entity, venue is alleged as proper in any judicial district. The complaint further asserts that the district will be a destination for the accused generic product.
• 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) oral tablets constitutes an act of patent infringement.
• Technical Context: The dispute concerns pharmaceutical patents for solriamfetol, a dopamine and norepinephrine reuptake inhibitor used to improve wakefulness in patients with excessive daytime sleepiness.
• Key Procedural History: The lawsuit was triggered by Defendant’s submission of ANDA No. 218725 and its subsequent Paragraph IV certification letters to Plaintiff. These letters asserted that the patents-in-suit are invalid and/or will not be infringed by the commercialization of Defendant's proposed generic product.

Case Timeline

Date	Event
2016-09-06	Earliest Priority Date for ’419 Patent
2020-03-19	Earliest Priority Date for ’362 Patent
2022-12-30	Earliest Priority Date for ’145 Patent
2023-08-10	Aurobindo's First Paragraph IV Notice Letter Sent (No earlier than)
2023-12-08	Aurobindo's Second Paragraph IV Notice Letter Sent (No earlier than)
2024-02-13	Aurobindo's Third Paragraph IV Notice Letter Sent (No earlier than)
2024-02-27	Aurobindo's Fourth Paragraph IV Notice Letter Sent (No earlier than)
2024-05-21	Aurobindo's Fifth Paragraph IV Notice Letter Sent (No earlier than)
2024-07-09	Aurobindo's Sixth Paragraph IV Notice Letter Sent (No earlier than)
2024-10-08	Aurobindo's Seventh Paragraph IV Notice Letter Sent (No earlier than)
2024-12-10	Aurobindo's Eighth Paragraph IV Notice Letter Sent (No earlier than)
2025-03-19	Aurobindo's Ninth Paragraph IV Notice Letter Sent (No earlier than)
2025-04-01	’145 Patent Issued
2025-06-03	’362 Patent Issued
2025-08-19	’419 Patent Issued
2025-09-10	Aurobindo's Tenth Paragraph IV Notice Letter Sent, covering patents-in-suit (No earlier than)
2025-11-14	Complaint Filing Date

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

U.S. Patent No. 12,263,145 - "Methods of Administering Solriamfetol to Lactating Women"

• Patent Identification: U.S. Patent No. 12,263,145, "Methods of Administering Solriamfetol to Lactating Women," issued April 1, 2025. (Compl. ¶8).

The Invention Explained

• Problem Addressed: The patent addresses the "shortcomings in the art" regarding the administration of solriamfetol to lactating subjects, noting the desire to reduce or minimize adverse effects in an infant fed breast milk from a subject treated with the drug. (’145 Patent, col. 2:27-32; col. 7:12-18).
• The Patented Solution: The invention provides a method that involves administering a daily dose of solriamfetol and then waiting for a specified period—at least 5 hours—before feeding the infant breast milk from the subject. (’145 Patent, Abstract). This delay is designed to allow the concentration of solriamfetol in the breast milk to decrease after its peak, thereby reducing the total amount of the drug ingested by the infant. (’145 Patent, col. 2:40-54). FIG. 1 of the patent visually depicts the pharmacokinetic profiles of solriamfetol in both plasma and breast milk, showing concentration peaking shortly after administration and declining thereafter, which supports the rationale for the claimed waiting period. (’145 Patent, FIG. 1).
• Technical Importance: The method provides a protocol to manage infant drug exposure, potentially allowing lactating individuals to continue necessary treatment for conditions like narcolepsy while also breastfeeding. (’145 Patent, col. 2:33-39).

Key Claims at a Glance

• The complaint asserts at least independent claim 1. (Compl. ¶40).
• Claim 1 requires:
  • A method for decreasing the potential for adverse events from solriamfetol in an infant fed breast milk obtained from a treated human subject.
  • Orally administering solriamfetol at a once-daily dose of about 75 mg.
  • Feeding the infant breast milk from the subject at least about 5 hours after administration.
  • Wherein the cumulative amount of solriamfetol excreted in breast milk over 8 hours is about 0.26 mg or lower.
• The complaint reserves the right to assert additional claims. (Compl. ¶42).

U.S. Patent No. 12,318,362 - "Methods of Providing Solriamfetol Therapy to Subjects with Impaired Renal Function"

• Patent Identification: U.S. Patent No. 12,318,362, "Methods of Providing Solriamfetol Therapy to Subjects with Impaired Renal Function," issued June 3, 2025. (Compl. ¶9).

The Invention Explained

• Problem Addressed: The patent notes that solriamfetol is eliminated from the body primarily through renal excretion. (’362 Patent, col. 2:36-39). Consequently, patients with impaired renal function would be expected to have higher drug exposure, which could lead to an increase in dose-dependent adverse effects such as headache, nausea, and anxiety. (’362 Patent, col. 2:27-36). It was not previously known what dosing regimen would be safe for this patient population. (’362 Patent, col. 2:47-51).
• The Patented Solution: The invention discloses specific dose-escalation schemes tailored to the degree of a patient's renal impairment. For moderately impaired patients, it teaches starting at a low initial dose (e.g., 37.5 mg) and waiting for a period of at least five to seven days to allow for tolerance development before increasing to a higher maximum dose (e.g., 75 mg). (’362 Patent, Abstract; col. 3:1-7). For severely impaired patients, it teaches a lower, single-level maximum daily dose. (’362 Patent, col. 3:9-12). The pharmacokinetic data presented in FIG. 1A demonstrates that as renal function declines, drug concentration in the plasma is significantly higher and persists for longer, illustrating the technical basis for the claimed dose adjustments. (’362 Patent, FIG. 1A).
• Technical Importance: The invention provides a method to safely administer solriamfetol to renally impaired patients, a population at higher risk of adverse events, thereby addressing an unmet medical need. (’362 Patent, col. 2:52-55).

Key Claims at a Glance

• The complaint asserts at least independent claim 1. (Compl. ¶49).
• Claim 1 requires:
  • A method of reducing toxicity from solriamfetol (APC) administration in a subject with moderate or severe renal impairment.
  • For a subject with moderate renal impairment (eGFR of about 30-59 mL/min/1.73 m²): providing a first oral daily dose of 37.5 mg APC for a period of at least 6 days, followed by a second oral daily dose of 75 mg APC.
  • For a subject with severe renal impairment (eGFR of about 15-29 mL/min/1.73 m²): providing an oral daily dose of 37.5 mg APC, not to be exceeded.
• The complaint reserves the right to assert additional claims. (Compl. ¶51).

U.S. Patent No. 12,390,419 - "Formulations of (R)-2-Amino-3-Phenylpropyl Carbamate"

• Patent Identification: U.S. Patent No. 12,390,419, "Formulations of (R)-2-Amino-3-Phenylpropyl Carbamate," issued August 19, 2025. (Compl. ¶10).
• Technology Synopsis: The patent addresses the technical challenge of formulating solriamfetol, a highly water-soluble drug, into an immediate-release tablet with a high drug load that dissolves quickly and consistently across the different pH environments of the gastrointestinal tract. (’419 Patent, col. 1:21-48). The patented solution is a compressed tablet formulation comprising a high percentage of the active pharmaceutical ingredient (90-98%), a small amount of a binder (1-5%), and a lubricant (0.1-2%), and which notably does not require a disintegrant to achieve rapid dissolution. (’419 Patent, Abstract; col. 1:49-2:16).
• Asserted Claims: At least independent claim 1 is asserted. (Compl. ¶58).
• Accused Features: The complaint alleges that Aurobindo’s proposed generic solriamfetol oral tablet products will have a formulation that infringes the ’419 Patent. (Compl. ¶¶1, 17, 60).

III. The Accused Instrumentality

Product Identification

• Aurobindo's proposed generic solriamfetol oral tablets, for which Defendant submitted Abbreviated New Drug Application No. 218725 to the FDA. (Compl. ¶1).

Functionality and Market Context

• The accused product is a generic version of Axsome's Sunosi®, a dopamine and norepinephrine reuptake inhibitor indicated to improve wakefulness in adults with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea. (Compl. ¶¶1, 11). The complaint alleges that Aurobindo seeks FDA approval to manufacture and market this generic product for the same indications prior to the expiration of the patents-in-suit, positioning it as a direct competitor to Sunosi®. (Compl. ¶¶1, 17, 26). The complaint does not provide specific details on the formulation of Aurobindo's proposed product but alleges it infringes the asserted patents.

IV. Analysis of Infringement Allegations

The complaint does not contain a detailed claim chart or element-by-element analysis of infringement. The infringement theories are predicated on the act of filing an ANDA for a product whose proposed labeling will allegedly instruct users to perform the methods claimed in the ’145 and ’362 patents, and whose physical composition will allegedly embody the formulation claimed in the ’419 patent. The following tables summarize the core of these allegations.

'145 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method for decreasing the potential for adverse events from solriamfetol in an infant fed breast milk... comprising: administering solriamfetol orally at a once-daily dose of about 75 mg to the subject;	Aurobindo's proposed product is a solriamfetol oral tablet, which will be prescribed in dosages including 75 mg for once-daily use for approved indications.	¶¶1, 11, 42	col. 29:6-10
and feeding the infant breast milk from the subject at least about 5 hours after administering the solriamfetol to the subject,	The proposed product label will allegedly instruct or encourage physicians and lactating patients to delay breastfeeding for at least 5 hours post-administration to reduce infant exposure.	¶¶43-44	col. 29:11-14
and the cumulative amount of solriamfetol excreted in breast milk over 8 hours is about 0.26 mg or lower.	The complaint alleges that following the instructions on the proposed label for the accused product will result in this outcome.	¶¶42-44	col. 29:15-17

• Identified Points of Contention:
  • Scope Questions: A central issue may be whether the language in Aurobindo's proposed product label constitutes active inducement of the claimed method. The analysis will question whether the label explicitly "instructs" the 5-hour delay, or if it merely provides pharmacokinetic data, such as that shown in Figure 1 of the '145 Patent, leaving the clinical decision to the physician's judgment.

'362 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A method of reducing toxicity due to... APC administration in a subject having moderate or severe renal impairment, said method comprising: (a) providing to a subject having... moderate renal impairment... a first oral daily dose equivalent to 37.5 mg APC from day one to day n₁, and a second oral daily dose equivalent to 75 mg APC starting on day n₂... wherein n₁ is an integer equal to or greater than 6	The proposed product label for Aurobindo's generic solriamfetol tablets will allegedly instruct physicians to prescribe this specific dose escalation regimen (37.5 mg for at least 6 days, then 75 mg) for patients with moderate renal impairment.	¶¶51-53	col. 49:26-36
or (b) providing to a subject having... severe renal impairment... an oral daily dose equivalent to 37.5 mg APC, wherein the renally impaired subject is not provided a daily dose exceeding a dose equivalent to 37.5 mg APC	The proposed product label will allegedly instruct physicians to prescribe a maximum daily dose of 37.5 mg for patients with severe renal impairment.	¶¶51-53	col. 49:50-51; col. 50:1-4

• Identified Points of Contention:
  • Technical Questions: The dispute may focus on the precise language of Aurobindo's proposed label. A key question will be whether the label's recommended dose escalation timeline for moderately impaired patients (the "n₁" value) literally meets the "greater than 6" day requirement of claim 1, or if it recommends a different timeframe that might support an argument of non-infringement. Figure 1A of the patent, which shows increased drug exposure in renally impaired patients, provides the technical rationale for why such specific dosing instructions are medically necessary. ('362 Patent, FIG. 1A).

V. Key Claim Terms for Construction

• The Term: "feeding the infant breast milk from the subject at least about 5 hours after administering the solriamfetol" (’145 Patent, Claim 1)

• Context and Importance: This term defines a critical action step of the method claim. In the context of an ANDA case, where infringement is assessed based on the proposed product label, the construction of this term will be central to the question of inducement. Practitioners may focus on whether providing pharmacokinetic data showing a drug concentration peak (as illustrated in '145 Patent, FIG. 1) is sufficient to teach or encourage a user to wait "at least about 5 hours," even without an explicit instruction to do so.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification describes the general problem of avoiding "peak concentrations of solriamfetol excreted in breast milk" and a general solution of reducing exposure, which could support interpreting the claim step as the natural consequence of being provided relevant PK data. (’145 Patent, col. 2:9-16, 7:25-29).
  • Evidence for a Narrower Interpretation: The claim language itself, along with the abstract and summary of the invention, repeatedly and specifically recites "at least about 5 hours," suggesting this is not a general concept but a specific, claimed timeframe that would need to be encouraged for infringement to be induced. (’145 Patent, Abstract; col. 2:42-44).

• The Term: "an integer equal to or greater than 6" (’362 Patent, Claim 1)

• Context and Importance: This term sets a specific minimum duration (n₁) for the initial, lower dose in moderately impaired patients before escalation. Its definition is critical because a proposed generic label that instructs a shorter duration (e.g., "after 5 days") would create a clear non-infringement argument. The patent's disclosure of other timeframes, such as "at least five days" or "at least seven days" in the summary and detailed description, may be used by either side to argue for or against flexibility in interpreting this claimed numerical limit. (’362 Patent, col. 2:65-3:2).

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification’s general discussion of allowing for "tolerance development" could be cited to argue that the precise number of days is less critical than the overall principle of a phased dose escalation. (’362 Patent, col. 3:6-7).
  • Evidence for a Narrower Interpretation: The plain language of the claim explicitly requires the integer n₁ to be "equal to or greater than 6." This explicit numerical limitation provides strong evidence that the claim requires a waiting period of at least a full six days. (’362 Patent, col. 49:31-32).

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents-in-suit. The theory of inducement is based on the allegation that Aurobindo, with knowledge of the patents, will sell its generic product with a label that will intentionally encourage and instruct medical professionals and patients to perform the patented methods of use. (Compl. ¶¶43, 52, 61). The contributory infringement allegation is based on the assertion that the accused product is not a staple article of commerce suitable for substantial non-infringing use. (Compl. ¶¶44, 53, 62).
• Willful Infringement: The complaint does not use the term "willful," but it alleges that the case is "exceptional" and requests an award of attorneys' fees under 35 U.S.C. § 285. (Compl. ¶¶47, 56, 65). This allegation is based on Aurobindo's alleged knowledge of the patents, evidenced by the series of Paragraph IV notice letters sent to Axsome. (Compl. ¶¶28-38).

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

• A core issue will be one of induced infringement: Will the proposed product label for Aurobindo’s generic drug be found to contain instructions that actively encourage physicians and patients to perform the specific, multi-step methods of the ’145 and ’362 patents, or will the label’s language be deemed to merely provide clinical data, leaving the ultimate method of administration to the independent medical judgment of the prescriber?
• A second key question will be one of compositional identity: For the ’419 formulation patent, the dispute will likely center on whether Aurobindo's product literally falls within the claimed formulation, specifically concerning the presence and percentages of the active ingredient, binder, and lubricant, and the notable absence of a disintegrant.
• Finally, an underlying issue for the court, though not detailed in the complaint, will be patent validity: Do the claimed methods of administration represent non-obvious improvements over the prior art, or were they merely the expected result of applying routine clinical dose-adjustment principles to a drug with known pharmacokinetic properties?