Liquidia Corporation announced that the U.S. Food and Drug Administration (FDA) provided an update on its review of the New Drug Application (NDA) for YUTREPIA?? (treprostinil) inhalation powder to treat pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD). The FDA informed the Company that it is confirming the process for adding the PH-ILD indication as an amendment to the NDA for YUTREPIA.

Accordingly, the FDA is not able to issue an action letter in time to meet the previously issued Prescription Drug User Fee Act (PDUFA) goal date of January 24, 2024, and their review remains ongoing. The FDA did not request any additional clinical data to support the NDA and did not issue a new PDUFA goal date. On November 5, 2021, the FDA issued a tentative approval for YUTREPIA for the treatment of PAH to improve exercise ability in adult patients with New York Heart Association (NYHA) Functional Class II-III symptoms. In July 2023, Liquidia filed an amendment to its New Drug Application for YUTREPIA, seeking to add PH-ILD to the label.

The FDA previously confirmed that YUTREPIA may include the treatment of PH-ILD to the proposed label for YUTREPIA without additional clinical studies. YUTREPIA also remains subject to ongoing litigation. Liquidia filed a request for Court Andrews of the U.S. District Court for the District of Delaware (District Court) to set aside the injunction that was instituted in August 2022 tied to litigation filed by United Therapeutics (UTHR) alleging patent infringement of U.S. Patent No.

10,716,793 (the '793 Patent) in Case No. On December 20, 2023, the United States Court of Appeals for the Federal Circuit (CAFC) affirmed the earlier decision by the Patent Trial and Appeal Board (PTAB), which found all claims of the '793 Patent to be unpatentable due to the existence of prior art cited by Liquidia in inter partes review proceedings. Additionally, in September 2023, UTHR filed a second complaint for patent infringement in District Court in Case No.

1:23-cv-00975-RGA (the New Hatch-Waxman Litigation). Therefore, the Company believes that final FDA approval for YUTREPIA will not be subject to any statutory 30-month stay arising from the New Hatch-Waxman litigation per Section 505(c)(3)(C) of the Federal Food, Drug and Cosmetic Act. Liquidia has completed INSPIRE, or investigation of the Safety and Pharmacology of Dry Powder Inhalation of Treprostinil, an open-label, multi-center phase 3 clinical study of YUTREPIA in patients diagnosed with PAH who are naive to inhaled treprostinil or who are transitioning from Tyvaso®?

(nebulized treprostinil).