United Therapeutics Corporation v. Liquidia Technologies, Inc.
1:23-cv-00975
| D. Del. | Oct 16, 2024Background
- United Therapeutics Corporation (UTC) sued Liquidia Technologies, Inc. alleging infringement of U.S. Patent No. 11,826,327, which covers methods of treating pulmonary hypertension associated with interstitial lung disease (PH-ILD) using treprostinil.
- UTC's TYVASO DPI is a dry powder inhaler product approved by the FDA for treating pulmonary arterial hypertension (PAH) and PH-ILD.
- Liquidia sought FDA approval for YUTREPIA, a dry powder treprostinil product, first for PAH and later for PH-ILD.
- The dispute focuses on the construction of key claim terms in the ’327 patent, after UTC amended its complaint to add this patent.
- The court conducted a Markman hearing and considered extensive arguments, expert testimony, and supplemental briefing from both parties on how to interpret the patent claims.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Construction of “a”/“the” (e.g., "a patient") | Ordinary meaning: “one or more” unless context dictates | Means “one and more than one” (argued some claims require plural) | “One or more” is proper; statistical significance handled at infringement stage |
| “Maximum tolerated dose” | Not indefinite; ordinary meaning is “highest dose without unacceptable adverse events” | Indefinite; or the highest dose before discontinuation | Not indefinite; ordinary meaning sufficient |
| “Pulsed inhalation device” | Device that provides non-continuous inhaled drug delivery, can be breath-powered | Device must itself provide the force for non-continuous delivery (not breath-powered) | Device that provides for non-continuous delivery; no external “force” limitation read in |
Key Cases Cited
- Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (central authority on claim construction, emphasizing importance of intrinsic evidence)
- Markman v. Westview Instruments, Inc., 52 F.3d 967 (Fed. Cir. 1995), aff'd, 517 U.S. 370 (1996) (establishes that claim construction is a question of law for the court)
- Deere & Co. v. Bush Hog, LLC, 703 F.3d 1349 (Fed. Cir. 2012) (claim construction must not import limitations from specification into claims)
- Verizon Servs. Corp. v. Vonage Holdings Corp., 503 F.3d 1295 (Fed. Cir. 2007) (disclosed examples in the specification should generally not be excluded by claim interpretation)
- Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898 (Fed. Cir. 2004) (claims should not be restricted unless there is clear intent in the specification)
- Merck & Co. v. Teva Pharms. USA, Inc., 395 F.3d 1364 (Fed. Cir. 2005) (claim construction should give meaning to all claim terms)