Merck has entered into a definitive agreement to acquire Idenix Pharmaceuticals, Inc. for approximately $3.9 billion in cash. Idenix, a biopharma company primarily focused on the development of next-generation oral antiviral therapeutics to treat hepatitis C virus (HCV) infection, has three HCV drug candidates in development: two nucleotide prodrugs (IDX21437 and IDX21459) and a NS5A inhibitor (samatasvir). These candidates are being evaluated for potential pan-genotypic fixed-dose combination r...