An estimated 3.2 million people in the United States are living with chronic hepatitis C infection, with most being unaware of the infection and showing no symptoms, according to the U.S. Centers for Disease Control and Prevention.
Sovaldi, which costs about $84,000 a year per patient, generated $2.3 billion in sales in the first few months on the market.
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Idenix's experimental drug, IDX21437, in combination with Merck's two experimental drugs, MK-5172 and MK-8742, has the potential to cure patients with every genotype of the hepatitis C virus within four-six weeks, Merck's research chief Roger Perlmutter told Reuters on Monday.
Without the Idenix drug, the two Merck drugs cured a "high nineties" percentage of patients after 12 weeks of treatment, he said.