United Therapeutics has struck a blow to Liquidia Technologies’ generic formulation of Tyvaso. With a court ruling the generic infringes a United patent, Liquidia faces the prospect of being kept off the market until 2027—unless it gets the decision overturned or prevails in a related dispute.
In recent years, United has been embroiled in a multifront patent row with Liquidia over generic versions of treprostinil, including an inhaled dry powder product. United has argued the formulation, branded Yutrepia, infringes several patents, including 10,716,793. The United States Patent and Trademark Office (USPTO) issued the ‘793 patent, which expires in May 2027, two years ago.
On Wednesday, Liquidia and United provided updates on the dispute over the ‘793 patent, which relates to a method of administering treprostinil via inhalation. The Delaware district court ruled that Liquidia would infringe the patent by marketing Yutrepia, adding that the generic drug developer failed to prove any claim of ‘793 is invalid.
United hailed the decision as a victory, noting that it expects the court to bar the FDA from granting final approval for Yutrepia until the ‘793 patent expires in 2027. Liquidia investors reacted negatively to the news, sending the company’s stock down 26% to around $4.30 when markets opened on Thursday. The decline followed another slump earlier in the week that added up to a 42% drop over five days.
Yet, Liquidia still has two shots at bringing Yutrepia to market before 2027. In July, the USPTO’s Patent Trial and Appeal Board found that all the ‘793 claims are unpatentable. If the decision is upheld, Liquidia expects to be able to secure final FDA approval by mid-2024.
That is one of two potential routes to a pre-2027 approval that are open to Liquidia. The other option is to seek and secure the reversal of the district court’s decision that Yutrepia infringes the ‘793 patent.