FDA Requested Additional Data Related to Idenix Pharmaceuticals IDX184 and IDX19368 -8K

In August 2012, Idenix Pharmaceuticals

announced that the Company received verbal notices from the U.S. Food and Drug Administration (FDA) that a partial clinical hold has been placed on IDX184, the Company's nucleotide polymerase inhibitor under development for the treatment of hepatitis C virus (HCV), and that a clinical hold has been placed on IDX19368, the Company's next generation nucleotide polymerase inhibitor under development for the treatment of HCV, due to the occurrence of a serious cardiac-related adverse event encountered with a competitor's nucleotide polymerase inhibitor for the treatment of HCV. The FDA has subsequently requested in writing additional data related to IDX184 and IDX19368. The Company has updated its general investor presentation to provide a summary of such requested additional data and the status of data collection with respect to IDX184, which is attached hereto as Exhibit 99.1. Exhibit 99.1 is incorporated by reference into this Current Report on Form 8-K.