Tyvaso® and Tyvaso® DPI (treprostinil inhalation powder)
Case Name: United Therapeutics Corp. v. Liquidia Techs., Inc., No. 25-368, 2025 WL 1549896 (M.D.N.C. May 30, 2025) (Schroeder, J.)
Drug Product and Patent(s)-in-Suit: Tyvaso® and Tyvaso® DPI (treprostinil inhalation powder); U.S. Patent No. 11,357,782 (“the ’782 patent”)
Nature of the Case and Issue(s) Presented: UTC’s ’782 patent claims a method for treating pulmonary hypertension (“PH”). PH manifests in different varieties, including pulmonary arterial hypertension (“PAH”) and pulmonary hypertension associated with interstitial lung disease (“PH-ILD”). UTC developed and sells Tyvaso to treat PH and PH-ILD. Tyvaso is administered to patients through a nebulizer, which is a device that aerosolizes a mist for inhalation. (Id. ¶ 2; Doc. 1-3 at 2.) Tyvaso DPI is administered via a dry powder inhaler (“DPI”). On August 19, 2024, Liquidia announced that it had obtained tentative FDA approval for Yutrepia, its own treatment for PAH and PH-ILD. Like Tyvaso DPI, Yutrepia is a “dry powder formulation of treprostinil” administered via a DPI. Although the FDA tentatively approved Yutrepia as a treatment for PH and PAH, it specified that final approval would not “be awarded until the expiration of UTC’s 3-year regulatory exclusivity for UTC's Tyvaso DPI on May 23, 2025.” On May 23, 2025, Liquidia reported that it received final approval for Yutrepia.
Prior to this litigation, UTC had asserted other patent alleging infringement of Yutrepia. After a 2022 bench trial, the D. Del. found that Yutrepia infringed UTC’s ’793 patent, a decision the Federal Circuit affirmed. The ’793 patent claimed a method of treating pulmonary hypertension comprising administering by inhalation to a human treprostinil with an inhalation device where the inhalation devise is a dry powder inhaler. But in a parallel proceeding, the PTAB found that the ’793 patent claims were unpatentable. UTC appealed and the Federal Circuit affirmed. Then, the D. Del. vacated the conflicting portion of its earlier judgment.
When Liquidia amended the Yutrepia NDA to add a PH-ILD indication, UTC brought another patent infringement lawsuit against Liquidia, this time asserting UTC’s ’327 patent. UTC’s motion for a preliminary injunction in that case was denied.
UTC filed the present action on May 9, 2025, and immediately requested that the court enter a TRO and preliminary injunction. The court denied UTC’s motion.
Why Liquidia Prevailed: Likelihood of success on the merits. UTC argued that the ’782 patent was not obvious because the following three elements: (i) the dosage; (ii) the number of breaths; and (iii) the minimum three-hour spacing between doses. But the PTAB, in its Final Written Decision invalidating the ’793 patent found the opposite conclusion with respect to the dosage and number of breaths associated with the method claims at issue in that case based on the same evidence. “This determination that the dosage and quantity of breaths claimed by the ‘793 patent were obvious and not patentable casts substantial doubt on [PTO Examiner’s] prior conclusion that seemingly identical claims in the ‘782 patent are not obvious.” And although the PTAB decision regarding the ‘793 patent did not address the 3-hour window between doses, the PTO Examiner during prosecution of the ’782 patent application concluded that a POSA would have found that the interval “is obvious as one would continue to treat a patient in need of treatment after the initial dose wore off. This is routine.” Because the court found there was a substantial question as to the validity of the ‘782 patent, it concluded that UTC had not shown that it was likely to prevail on the merits of its claim.
Irreparable harm. The court first addressed UTC’s delay in bringing a patent infringement action based on the ’782 patent. The ‘782 patent issued in June 2022 when UTC would have been aware of any potential infringement claim by then. If UTC believed that harm was not sufficiently imminent in March 2024, it was nearer at hand in August 2024, when Liquidia announced that Yutrepia had been granted tentative FDA approval for PAH and PH-ILD indications. Any immediacy would have been even more apparent on November 26, 2024, when Liquidia filed its proposed label for Yutrepia (and accompanying instructions) that UTC cited as a basis for its claim of infringement in its current complaint.
The court found that it was probable that if Yutrepia launches, UTC will see some erosion in its prices, but the extent of it appears speculative. Lost sales alone are insufficient to prove irreparable harm; if they were, irreparable harm would be found in every case involving a manufacturer/patentee, regardless of circumstances. Moreover, Liquidia has provided evidence, based on UTC’s own projections, that UTC contemplated consistent increased sales and prices through 2035. Finally, in a market where increasing numbers of patients are being diagnosed with the relevant illness and UTC was not projected to provide treatment for them, a claim of lost market share loses some force. The court also found it worth noting that Yutrepia is not a generic for Tyvaso and their products are not necessarily interchangeable. “The evidence that most undermines UTC’s claims of irreparable harm, however, is the public statements of its executives. UTC’s own management has publicly advised investors that Yutrepia does not pose a competitive threat to the company. As late as this month, its management is reported to have predicted that Liquidia “is not a commercial threat due to undifferentiation across the board.”
Balance of the Equities. The court found this factor was a wash.
Public Interest. Given the court’s substantial question regarding the validity of the ‘782 patent, “the evidence strongly suggesting that PH and PH-ILD patients are likely to benefit from the use of Yutrepia, and the fact that UTC does not currently meet the patient need for PH and PH-ILD treatment and would not likely do so in the near future if an injunction were entered, the court concludes that the public interest favors Liquidia and the denial of injunctive relief.”
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