McDermott Will & Schulte wins significant patent trial against Liquidia over YUTREPIA® PH-ILD treatment

Global law firm McDermott Will & Schulte secured a significant trial victory on behalf of United Therapeutics Corporation (UTC) in its Hatch-Waxman litigation against Liquidia Technologies in the US District Court for the District of Delaware.

On September 30, 2026, US District Judge Richard G. Andrews issued a Trial Opinion in United Therapeutics Corporation v. Liquidia Technologies, Inc., C.A. No. 23-975-RGA. The court held that Liquidia failed to prove claims 1 and 14 of US Patent No. 11,826,327 (the ’327 patent) invalid and found that Liquidia infringes.

The case concerned the ’327 patent, which describes methods of treating pulmonary hypertension associated with interstitial lung disease (PH-ILD) by administering treprostinil. Following a four-day bench trial in June 2025, the court found that Liquidia infringes and rejected Liquidia’s invalidity challenges to claims 1 and 14, including obviousness, prior sale, and inherent anticipation. The win puts Liquidia’s continued ability to market YUTREPIA® at risk.

This follows a series of wins for UTC in litigation involving Liquidia in which UTC has relied on the McDermott team to enforce its IP rights including in federal district courts, North Carolina Business Court, the PTAB, Court of Appeals for the Federal Circuit, and the Supreme Court.

The team was led by Doug Carsten and Adam Burrowbridge, and included Art Dykhuis, Ian Brooks, Katherine Pappas, Lillian Spetrino, Courtney Seams, Jake Vallen, Benjamin Ediger, and Keval Amin, with additional support from Allison Shook, Erick Ramirez, and Joanie Rice.