United Therapeutics has filed a patent infringement suit against Liquidia Technologies in the US District Court for the District of Delaware alleging infringement of US patents 9,604,901 and 9,593,066, which protect Tyvaso treprostinil inhalation solution. Both patents are titled “Process to prepare treprostinil, the active ingredient in Remodulin” and both expire in December 2028.
In April 2020, the FDA accepted Liquidia’s 505(b)(2) NDA for its LIQ861 treprostinil DPI for the treatment of pulmonary arterial hypertension. Liquidia had filed petitions with the US Patent and Trademark Office seeking to invalidate the two patents in question in March 2020. The lawsuit prevents the FDA from approving the NDA until the litigation is resolved or for 30 months, whichever comes first.
Read the United Therapeutics press release.
