Liquidia will pay $380.7 million to United Therapeutics and other parties to settle six lawsuits spanning patent infringement, trade secret and antitrust claims, ending a seven-year legal battle over treprostinil products and removing the PH-ILD indication from its sole commercial drug, Yutrepia.

The settlement, announced this past week, resolves antitrust litigation launched in 2019, when Sandoz Group and its then-marketing partner RareGen — since merged into Liquidia — accused United Therapeutics of blocking a generic version of injectable treprostinil, FDA-approved since 2002 and marketed as Remodulin. It also closes the patent dispute triggered by a September 30 ruling from the U.S. District Court for the District of Delaware, where Judge Richard G. Andrews found Liquidia infringed claims 1 and 14 of United's U.S. Patent No. 11,826,327. That ruling sent Liquidia shares down 57%, from $70.69 to $30.26.

Liquidia chose not to appeal. Instead, it agreed to drop pulmonary hypertension associated with interstitial lung disease (PH-ILD) from Yutrepia's label and stop promoting the inhaled treprostinil powder to new PH-ILD patients. The company keeps the PAH indication and its remaining development programs, including Raynaud's phenomenon associated with systemic sclerosis (SSc-RP), which received FDA Fast Track designation last month with no approved therapy on the market. Liquidia also continues developing L606, a twice-daily liposomal treprostinil inhalation suspension delivered via a next-generation nebulizer, in partnership with Pharmosa Biopharm for both PH-ILD and PAH.

What does the settlement cost Liquidia?

The payment schedule, detailed in a regulatory filing, runs through 2027:

• $175 million to United Therapeutics by October 30, extendable by up to six 30-day periods, resolving the antitrust claims tied to treprostinil injection.
• $145.4 million to United Therapeutics in two equal installments of $72.7 million, due on or before January 31, 2027, and April 30, 2027.
• $60.3 million this month to parties with interests in the antitrust lawsuit, including United and ICU Medical, which acquired cartridge maker Smiths Medical ASD in 2022.

Liquidia also terminated its promotional agreement for treprostinil injection and will no longer support that product commercially. The company reported $396.1 million in cash and cash equivalents as of September 30.

How did the market and analysts respond?

Liquidia shares surged nearly 27% on Wednesday, the first trading day after the announcement, from $26.81 to $33.94, climbed 2.5% to $34.78 Thursday, and slipped 1% to $34.35 Friday — a 25% five-day gain. United Therapeutics shares fell 3% for the week, closing Friday at $533.12.

Analysts split on the verdict. Jefferies senior biotech equity researcher Manoj Eradath, PhD, wrote: "We view this as a very favorable outcome for LQDA and broadly in line w/ the base case we previously outlined." Eradath, who raised Jefferies' 12-month price target on Liquidia 22%, from $45 to $55, said the settlement removes investor fears of a Yutrepia sales interruption and clears uncertainty around L606's PH-ILD pathway. Needham senior biotech analyst Serge Belanger agreed, writing that the deal "allows LQDA to build the blockbuster presence in PAH," as reported by Investor's Business Daily.

Two others called it for United. J.P. Morgan managing director Jessica Fye wrote: "We see a framework in place that should allow for a substantial proportion of current PH-ILD patients on Yutrepia to transition to Tyvaso, and we think much of this process could occur over the next two quarters." Jefferies analyst Roger Song, MD, called the settlement a "decisive win" for United, which preserved PH-ILD exclusivity through treprostinil and "extracted meaningful economics from LQDA."

How large is the revenue at stake?

Yutrepia generated $300.263 million in net product sales in the first six months of this year, against $6.517 million in January–June 2025, reflecting its U.S. launch on June 2, 2025 after final FDA approval on May 23 of last year. On a conference call, CEO Roger Jeffs, PhD, and COO/CFO Michael Kaseta disclosed unaudited Q3 net sales of $222.7 million — up 31%, or roughly $52 million, from Q2's $170.382 million — driven primarily by PAH prescriptions.

Sales split 60/40 between PAH and PH-ILD, with PAH trending toward 70%, a shift Eradath said "suggest[s] the commercial impact from removal of PH-ILD may be lower than initially expected." Liquidia projects Yutrepia will exceed $1 billion in annual sales by 2028.

United's two inhalable treprostinil products, Tyvaso and Tyvaso DPI, combined for $910.1 million in January–June, with Tyvaso DPI the top seller at $656.9 million. United, founded in 1996 as LungRx by chairperson and CEO Martine Rothblatt, PhD, said it had offered Liquidia a pre-ruling settlement that would have preserved both indications, and claimed Liquidia used United's Tyvaso clinical trial data in PH-ILD to build Yutrepia's development case.

Fye noted the PH-ILD patient shift offers a timely lift while United awaits an FDA decision, expected in late April, on a Tyvaso indication for idiopathic pulmonary fibrosis. Ralinepag, United's once-daily oral prostacyclin receptor agonist for PAH, carries a PDUFA target action date of June 24, 2027 — milestones that will now compete for investor attention with Yutrepia's PAH growth and the L606 pipeline Liquidia retained.