DCT

2:25-cv-03533

Aurinia Pharma Inc v. Difgen Pharma LLC

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-03533, D.N.J., 04/30/2025
  • Venue Allegations: Plaintiff alleges venue is proper in the District of New Jersey because Defendant maintains a regular and established place of business in the district and has committed an act of infringement there.
  • Core Dispute: Plaintiff alleges that Defendant’s filing of an Abbreviated New Drug Application (ANDA) to market a generic version of the drug LUPKYNIS® (voclosporin) constitutes an act of infringement of two patents covering methods of treating lupus nephritis.
  • Technical Context: The technology concerns pharmacodynamic treatment protocols for lupus nephritis, a severe autoimmune kidney disease, using the calcineurin inhibitor voclosporin.
  • Key Procedural History: This action was initiated under the Hatch-Waxman Act following a notice letter, dated March 17, 2025, in which Defendant informed Plaintiff of its ANDA filing containing a Paragraph IV certification. Plaintiff’s branded drug, LUPKYNIS®, received FDA approval on January 22, 2021, and the patents-in-suit are listed in the FDA’s Approved Drug Products with Therapeutic Equivalence Evaluations (the "Orange Book").

Case Timeline

Date Event
2017-05-12 '036 and '991 Patent Priority Date
2019-05-14 '036 Patent Issue Date
2021-01-22 FDA Approval of Aurinia's LUPKYNIS® (NDA)
2023-04-11 '991 Patent Issue Date
2025-03-17 DifGen sends Paragraph IV Notice Letter to Aurinia
2025-04-30 Complaint Filing Date

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

U.S. Patent No. 10,286,036 - Protocol for Treatment of Lupus Nephritis, issued May 14, 2019

The Invention Explained

  • Problem Addressed: The patent describes that the standard of care for lupus nephritis (LN) has limited success, with complete remission achieved in less than 10% of subjects, and that treatment with potent drugs like voclosporin can cause undesirable side effects, such as a decrease in the estimated glomerular filtration rate (eGFR), a key measure of kidney function (’036 Patent, col. 1:36-46, col. 2:61-64).
  • The Patented Solution: The invention is a "pharmacodynamic method" for treating proteinuric kidney diseases like LN. The protocol involves administering voclosporin, monitoring the patient's eGFR, and then adjusting the dosage—specifically, reducing or stopping it—if the eGFR decreases by a target percentage to below a predefined value. This personalized approach aims to maximize therapeutic benefit while minimizing kidney-related side effects (’036 Patent, Abstract; col. 3:1-19). The patent includes a figure illustrating the design of a clinical study protocol upon which the pharmacodynamic treatment is based (’036 Patent, FIG. 1).
  • Technical Importance: The claimed method provides a structured, data-driven protocol for managing a powerful but potentially toxic therapy, moving beyond a one-size-fits-all approach to treating a complex autoimmune disease (’036 Patent, col. 2:20-24).

Key Claims at a Glance

  • The complaint asserts infringement of at least one claim, and the lead independent claim is Claim 1 (Compl. ¶28).
  • Claim 1 requires:
    • A pharmacodynamic method to treat a proteinuric kidney disease by administering effective amounts of voclosporin for at least 24 weeks.
    • Assessing the patient's eGFR at a first time point and a second time point.
    • If the eGFR decreases by more than a "target % in the range of 20-45%" to below a "predetermined value in the range of 50-90 ml/min/1.73 m²," then reducing or stopping the voclosporin dosage.
    • If the eGFR decreases by less than the target percentage, then continuing the same dosage.
  • The complaint is silent on the assertion of dependent claims.

U.S. Patent No. 11,622,991 - Protocol for Treatment of Lupus Nephritis, issued April 11, 2023

The Invention Explained

  • Problem Addressed: As a continuation-in-part of the '036 patent, the '991 Patent addresses the same technical problem of balancing efficacy and safety in the treatment of LN (’991 Patent, col. 1:26-49).
  • The Patented Solution: The '991 Patent claims a more specific method of treating LN. It recites administering a defined starting dose of voclosporin (23.7 mg twice daily) in combination with mycophenolate mofetil (MMF) and corticosteroids, monitoring eGFR, and administering a specific "reduced dose" (15.8 mg or 7.9 mg twice daily) if the eGFR decreases within a specified range (’991 Patent, Abstract; col. 3:40-61). The patent also provides clinical trial data showing complete and partial remission rates for different dosage groups, which supports the claimed protocol's effectiveness (’991 Patent, FIG. 2).
  • Technical Importance: This patent refines the treatment protocol with specific dosages and decision points derived from clinical trial results, offering physicians a more concrete, evidence-based roadmap for personalizing therapy (’991 Patent, col. 2:10-24).

Key Claims at a Glance

  • The complaint asserts infringement of at least one claim, with Claim 1 being a representative independent claim (Compl. ¶40).
  • Claim 1 requires:
    • A method of treating LN by first selecting a patient and determining their baseline eGFR.
    • Administering a combination of voclosporin, MMF, and corticosteroids, with the voclosporin starting at 23.7 mg twice daily.
    • Assessing the patient's eGFR at a second time point.
    • Administering a reduced voclosporin dose of 15.8 mg or 7.9 mg twice daily if the eGFR decreases by ">20% to <30%" to a level below 60 ml/min/1.73 m².
  • The complaint is silent on the assertion of dependent claims.

III. The Accused Instrumentality

Product Identification

The complaint identifies Defendant’s generic voclosporin products, for which it seeks FDA approval through ANDA No. 220332 (Compl. ¶1).

Functionality and Market Context

The complaint alleges that the accused generic products are "the same, or substantially the same, as Aurinia's LUPKYNIS®" (Compl. ¶19). The infringement theory is based on the use of these products. It is alleged that upon approval, Defendant’s products will be prescribed by physicians and used by patients for the treatment of lupus nephritis according to a proposed package insert that will instruct users to perform the patented methods (Compl. ¶29, 31, 41, 43).

IV. Analysis of Infringement Allegations

The complaint provides a high-level notice of infringement consistent with the requirements for an ANDA action but does not contain a claim chart or detailed, element-by-element mapping of the accused conduct to the patent claims. The infringement theory articulated is that Defendant’s submission of its ANDA is a statutory act of infringement under 35 U.S.C. § 271(e)(2), and that the future commercial use of the generic product, as directed by its proposed label, will constitute direct and indirect infringement of the asserted patents (Compl. ¶25, 28-31, 37, 40-43).

  • Identified Points of Contention:
    • Evidentiary Questions: The central infringement question will depend on the specific language within Defendant's proposed product label. The key inquiry for the court will be whether the label’s instructions on dosing, patient monitoring (specifically eGFR), and subsequent dose adjustments "recommend, suggest, encourage, and/or instruct" (Compl. ¶31, 43) physicians and patients to perform the steps as recited in the asserted claims of the '036 and '991 patents.
    • Scope Questions: The dispute may center on the scope of the claimed method steps. For the '036 Patent, a question may be whether the instructions on the accused label fall within the claimed eGFR decrease "target % in the range of 20-45%." For the '991 Patent, which recites more specific parameters, a key question will be whether the label directs a dose reduction that aligns with the claimed "reduced dose of 15.8 mg BID or 7.9 mg BID" when triggered by an eGFR decrease in the "range of >20% to <30%."

V. Key Claim Terms for Construction

  • The Term: "reducing the daily dosage" (’036 Patent, Claim 1) versus "administering to the subject a reduced dose of 15.8 mg BID or 7.9 mg BID" (’991 Patent, Claim 1).

    • Context and Importance: These terms define the core action step of the pharmacodynamic protocols. The construction of these terms will be critical to determining infringement, as the specificity of the dose reduction instructed by Defendant's label will be compared against them. A narrow construction could allow Defendant to design around the claims by instructing a slightly different dose reduction.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification of the '036 patent discloses that dosages can be in "increments of 7.9 mg" and mentions several specific dosages, which a party could argue supports a construction of "reducing" that is not limited to any single value (’036 Patent, col. 2:42-44).
      • Evidence for a Narrower Interpretation: A party could argue that the explicit recitation of "15.8 mg BID or 7.9 mg BID" in Claim 1 of the '991 patent defines the "reduced dose" precisely. This is supported by the specification's discussion of the clinical study where capsules containing 7.9 mg were used, making a reduction to two capsules (15.8 mg) or one capsule a specific, intended embodiment (’991 Patent, col. 7:7-14).

  • The Term: "assessing the estimated Glomerular Filtration Rate (eGFR)" ('036 Patent, Claim 1; '991 Patent, Claim 1).

    • Context and Importance: This term is the central monitoring step that triggers the dose adjustment. Practitioners may focus on this term because different mathematical formulas can be used to estimate GFR, and the specific method used could be a point of contention.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification explicitly mentions two different suitable methods for calculating eGFR: the "Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI)" and the "Modification of Diet in Renal Disease (MDRD) Study equation." This disclosure may support a construction that encompasses any standard, clinically accepted method for assessing eGFR (’036 Patent, col. 4:19-24).
      • Evidence for a Narrower Interpretation: A party might argue that because the clinical trial data underlying the patent relied on the CKD-EPI equation, the term "assessing the eGFR" should be limited to that specific method as it was the basis for the observed results and claimed parameters (’036 Patent, col. 7:23-26).

VI. Other Allegations

  • Indirect Infringement: The complaint alleges inducement of infringement, stating that Defendant knows its proposed package insert will instruct healthcare professionals and patients to use the generic product in a manner that directly infringes the asserted claims (Compl. ¶31, 43). It also pleads contributory infringement, alleging the generic product is a material part of the invention, is especially adapted for an infringing use, and is not a staple article of commerce suitable for substantial non-infringing use (Compl. ¶32-33, 44-45).
  • Willful Infringement: The complaint does not use the word "willful" but alleges that Defendant has had "actual knowledge" of the patents since at least the date of its ANDA filing and the date of its notice letter, March 17, 2025 (Compl. ¶27, 39). These allegations could form the basis for seeking enhanced damages for any post-suit infringement.

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

  • A central issue will be one of instructed use: Does the precise language of Defendant’s proposed generic drug label direct, recommend, or otherwise encourage physicians and patients to follow the multi-step treatment protocol—including specific dosing, eGFR monitoring, and dose-adjustment thresholds—as recited in the asserted patent claims?
  • A key legal question will be one of scope and equivalency: Will the court construe the claims narrowly to the exact numerical parameters disclosed in the patents’ clinical trials (e.g., a ">20% to <30%" eGFR decrease), or more broadly? The answer will determine if Defendant’s product label must be a verbatim copy to infringe, or if instructions that are merely similar in function and result are sufficient.
  • The case will likely turn on an evidentiary comparison: The court will need to resolve the factual dispute over whether the administration of Defendant’s generic product, when used as instructed by its label, will necessarily result in the practice of every element of at least one asserted claim.