UTC, Liquidia Clash on Xarelto Patent Ruling’s Tyvaso Impact

United Therapeutics Corp. and Liquidia Corp. filed dueling letters in Delaware federal court debating whether a Federal Circuit ruling that struck down part of a patent for Bayer’s blockbuster Xarelto bolsters UTC’s defense of its Tyvaso lung drug or Liquidia’s attack on it.

A Sept. 23 precedential decision by the US Court of Appeals for the Federal Circuit invalidated claims in Bayer AG’s US Patent No. 10,828,310 as anticipated and obvious. The patent covered the use of the blood-thinning drug with aspirin to reduce cardiovascular risk.

The three-judge panel ruled the phrase “clinically proven effective” added nothing beyond fixed dosages ...