A US jury has ordered pharmaceutical giant Gilead Sciences to pay $2.5 billion to competitor Merck in a patent infringement case involving a drug used to treat hepatitis C, the two companies said.
A federal jury in Delaware on Thursday sided with Merck subsidiary Idenix, which claimed that Gilead's blockbuster sofosbuvir drug and its derivatives, sold under the labels Solvadi et Harvoni, violated one of its patents.
"The patent at issue in this case facilitated significant advances in the treatment of patients with HCV infection and was appropriately granted," Merck said in a statement.
"Achieving these advancements required many years of research and significant investment by our subsidiary and its partners," it added.
Gilead announced plans to appeal the ruling, and said the decision would not affect its ability to supply the drug to US patients.
Sofosbuvir came under the Gilead portfolio in 2011, when the biotech company acquired Pharmasset, which held the drug's patent.
Hepatitis C, a blood-borne viral disease, affects 130 to 150 million people globally and can result in liver cirrhosis or cancer.
According to the World Health Organization, it is responsible for 700,000 deaths yearly.
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