DCT

1:23-cv-00975

United Therap Corp v. Liquidia Tech Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:23-cv-00975, D. Del., 11/30/2023
  • Venue Allegations: Venue is based on Defendant's incorporation in Delaware and its intent to commercialize the accused product throughout the United States, including Delaware.
  • Core Dispute: Plaintiff alleges that Defendant’s New Drug Application for YUTREPIA®, a dry powder formulation of treprostinil, constitutes an act of infringement of patents related to methods of administering treprostinil by inhalation.
  • Technical Context: The technology concerns inhaled formulations of the drug treprostinil for treating pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD), serious conditions affecting blood pressure in the lungs.
  • Key Procedural History: In a prior action, a court found that the accused product infringes the ’793 Patent. The complaint also notes that claims of the ’793 Patent were subject to an Inter Partes Review (IPR) proceeding at the Patent Trial and Appeal Board and that the Board's decision was on appeal at the time of this complaint's filing.

Case Timeline

Date Event
2006-05-15 ’793 Patent Priority Date
2009-01-01 Plaintiff's TYVASO® (treprostinil) inhalation solution first approved by FDA
2020-04-17 ’327 Patent Priority Date
2020-07-21 ’793 Patent Issued
2022-01-01 Plaintiff's TYVASO DPI® (treprostinil) inhalation powder approved by FDA
2022-09-09 Judgment entered in prior action finding infringement of ’793 Patent
2023-07-24 Defendant notifies Plaintiff of amended New Drug Application for accused product
2023-11-28 ’327 Patent Issued
2023-11-30 Complaint Filed

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

U.S. Patent No. 10,716,793 - "Treprostinil Administration by Inhalation"

The Invention Explained

  • Problem Addressed: The patent addresses the lack of treatments for pulmonary hypertension that can be administered using a compact, portable inhalation device, such as a metered dose inhaler, which would grant patients greater autonomy compared to continuous intravenous or nebulized therapies. (’793 Patent, col. 2:60-64).
  • The Patented Solution: The invention is a method for treating pulmonary hypertension by administering a specific dose of treprostinil (15 to 90 micrograms) in a "single event" consisting of a very small number of breaths (1 to 3). (’793 Patent, Claim 1). This method is designed to enable rapid administration using a simple inhalation device. (’793 Patent, col. 8:59-65).
  • Technical Importance: The method provides a means for rapid, patient-administered inhalation therapy for a serious disease, potentially replacing more burdensome administration routes. (’793 Patent, col. 1:18-22).

Key Claims at a Glance

  • The complaint asserts one or more claims of the patent, and notes that Defendant's Paragraph IV notice letter did not dispute infringement of claims 1, 4, or 6-8 (Compl. ¶20, ¶31). Independent claim 1 is central.
  • Claim 1 requires:
    • A method of treating pulmonary hypertension in a human patient.
    • Administering by inhalation a "therapeutically effective single event dose" of a treprostinil formulation using an inhalation device.
    • The dose must comprise from 15 to 90 micrograms of treprostinil.
    • The dose must be "delivered in 1 to 3 breaths."

U.S. Patent No. 11,826,327 - "Treatment For Interstitial Lung Disease"

The Invention Explained

  • Problem Addressed: The patent identifies a need for new pharmaceutical treatments for interstitial lung disease (ILD), a group of lung diseases with a high mortality rate for which few treatments exist. (’327 Patent, col. 2:33-35).
  • The Patented Solution: The invention provides a method for improving exercise capacity in patients who have pulmonary hypertension associated with ILD. (’327 Patent, Abstract). The method involves administering by inhalation an effective amount of treprostinil of at least 15 micrograms in a "single administration event," with each breath delivering at least 6 micrograms of the drug. (’327 Patent, Claim 1).
  • Technical Importance: This method offers a targeted therapy for a specific subset of patients (PH-ILD) aimed at improving a key clinical outcome—exercise capacity—as measured by the 6-minute walk distance. (’327 Patent, col. 54:1-5).

Key Claims at a Glance

  • The complaint asserts one or more claims of the patent (Compl. ¶53). Independent claim 1 is central.
  • Claim 1 requires:
    • A method of improving exercise capacity in a patient with pulmonary hypertension associated with interstitial lung disease.
    • Administering by inhalation an effective amount of treprostinil.
    • The dose must be at least 15 micrograms up to a maximum tolerated dose.
    • The dose must be delivered in a "single administration event."
    • The event must comprise "at least 6 micrograms per breath."

III. The Accused Instrumentality

Product Identification

The accused instrumentality is Defendant Liquidia's YUTREPIA® (treprostinil) for inhalation, a proposed drug product that is the subject of New Drug Application ("NDA") No. 213005 (Compl. ¶3).

Functionality and Market Context

  • The complaint identifies YUTREPIA® as a "dry powder formulation of treprostinil" intended for the U.S. market (Compl. ¶2).
  • The complaint alleges that Liquidia has submitted its NDA to the FDA seeking approval for commercial manufacture, use, and sale of YUTREPIA® for treating pulmonary hypertension, positioning it as a direct competitor to Plaintiff's TYVASO® products (Compl. ¶2, ¶3, ¶12). The complaint further alleges that Liquidia has engaged in "pre-commercial launch activities" and has "expanded our top-tier sales force" in anticipation of FDA approval (Compl. ¶28, ¶8).
  • No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not provide a detailed, element-by-element infringement analysis or include a claim chart. The infringement allegations are based on the statutory act of infringement under the Hatch-Waxman Act, 35 U.S.C. § 271(e)(2), which defines the submission of an NDA for a generic or follow-on drug as an act of infringement if the drug would infringe a valid patent upon commercialization (Compl. ¶33, ¶55). The complaint alleges that the commercial manufacture, use, or sale of YUTREPIA®, if approved, will infringe one or more claims of the patents-in-suit (Compl. ¶34, ¶56).

  • Identified Points of Contention: Lacking a detailed infringement theory in the complaint, the central disputes will likely emerge during discovery and claim construction. Based on the claim language, key questions may include:
    • Technical Questions:
      • For the ’793 Patent, what is the precise dosing protocol for the accused YUTREPIA® dry powder inhaler, and can its administration be characterized as being "delivered in 1 to 3 breaths"?
      • For the ’327 Patent, what evidence will show that the accused product delivers "at least 6 micrograms per breath" to a patient with PH-ILD, and that its use results in "improving exercise capacity"?
    • Scope Questions:
      • Does the accused product's administration regimen constitute a "single event" or "single administration event" as those terms are understood in the context of the patents?

V. Key Claim Terms for Construction

"single event dose" / "single administration event" (’793 Patent, Claim 1; ’327 Patent, Claim 1)

  • Context and Importance: The definition of what constitutes a "single event" of administration is fundamental to the scope of both patents. Whether the accused product's use instructions fall within this definition will be a central point of the infringement analysis.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specifications do not appear to provide an explicit definition, which may suggest the terms should be given their plain and ordinary meaning to one of skill in the art, potentially covering any discrete, uninterrupted dosing session.
    • Evidence for a Narrower Interpretation: The ’793 Patent specification states that a "single administering event can be carried out in a limited number of breaths" and that the "total time... can be less than 5 minutes, or less than 1 minute, or less than 30 seconds" (’793 Patent, col. 8:59-65). This language could be used to argue for a narrow construction limited to very rapid, nearly instantaneous dosing sessions.

"delivered in 1 to 3 breaths" (’793 Patent, Claim 1)

  • Context and Importance: This term defines the core administration protocol of the claimed method. Infringement will depend on whether the accused dry powder product is used in a manner that delivers the full therapeutic dose within this strict breath count.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A party might argue this term refers to the intended or instructed number of breaths, regardless of minor patient-to-patient variability in inhalation technique.
    • Evidence for a Narrower Interpretation: The claim language is precise. A party could argue that infringement requires evidence that the full 15-90 microgram dose is consistently and reliably delivered to the lungs within exactly one, two, or three breaths, potentially excluding devices where dosing is less controlled. The patent's Example 1 describes delivering doses "in 2 breaths" or "3 breaths" (’793 Patent, col. 9:8-10).

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that upon FDA approval, Liquidia will induce infringement by instructing users via the product label to use YUTREPIA® in an infringing manner. It also alleges contributory infringement, stating the product has no substantial non-infringing uses (Compl. ¶43-47, ¶65-69).
  • Willful Infringement: Willfulness is alleged for both patents. For the ’793 Patent, the allegation is based on the prior district court judgment of infringement against Liquidia (Compl. ¶36, ¶50). For the ’327 Patent, the allegation is based on Liquidia's alleged awareness of the patent's existence prior to the lawsuit, as stated in a court filing in the related action (Compl. ¶24, ¶57-58).

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

  • A primary issue will be the validity of the ’793 Patent. The complaint acknowledges that the patent was the subject of an IPR proceeding that was on appeal at the time of filing. The outcome of that appeal will be dispositive for the claims against the ’793 Patent.
  • A key evidentiary question will be one of technical operation. Does the administration protocol for the YUTREPIA® dry powder inhaler meet the specific dosage and breath-count limitations recited in the asserted method claims (e.g., "delivered in 1 to 3 breaths," "at least 6 micrograms per breath"), and can Plaintiff produce evidence to prove this?
  • A central question of claim construction will be the definition of a "single event." The case may turn on whether this term is construed narrowly to mean a rapid, time-limited administration, or more broadly to cover any discrete dosing session as instructed on the accused product's label.