Merck fails to resurrect its $2.5B hep C patent win as appeals court rules for Gilead

Merck & Co. and Gilead Sciences have been battling over hepatitis C drug patents for years, and at one point Merck won a $2.54 billion verdict against its rival. But the latest victory in the battle goes to Gilead.

The U.S. Court of Appeals for the Federal Circuit upheld (PDF) a lower court’s ruling that tossed a 2016 verdict against Gilead worth $2.54 billion. A Delaware jury originally issued the patent infringement verdict, but Gilead won on appeal last year. 

RELATED: Gilead wins reversal of $2.54B hepatitis C patent verdict, but Merck says fight not over yet 

The case traces back to a 2013 lawsuit filed by Merck subsidiary Idenix Pharmaceuticals, alleging Gilead's lucrative hepatitis C meds Harvoni and Sovaldi violated its patent. Wednesday, the Federal Circuit sided with Gilead, agreeing that Idenix's patent was invalid.

In statements to Reuters, Merck said it’s considering further options, while Gilead said it’s confident the decision would be upheld if Merck decides to appeal again.

RELATED: Merck asks SCOTUS for its $200M in Gilead patent dues, never mind the misconduct 

In another hep C patent fight between the companies, Merck last year appealed to the Supreme Court to try to revive a $200 million jury verdict after a lower court tossed it out, citing attorney misconduct.

In that case, a judge overturned the verdict after she found a “pervasive” pattern of misconduct by the company's attorney and “fabricated” testimony throughout the process. The Supreme Court didn't take up the case.