Actelion revealed on Sunday that it could have to pay the sum after losing a lawsuit against Asahi Kasei Pharma in a California court.
A jury found against the company on Friday evening and awarded the company “up to 547 million US dollars”, said Actelion. The jury would meet to consider punitive damages on Tuesday, it added.
“The company is disappointed, but respectful of the jury’s verdict in this ongoing litigation,” the statement said.
Once the jury has concluded its deliberations, Actelion would consider its response, “including (but not limited to) an appeal,” the statement added.
The dispute dates back to November 2008 when Asahi filed suit over the cancellation of an agreement with Actelion subsidiary Cotherix to licence and develop a drug compound called fasudil.