CAMBRIDGE, Mass., Aug. 27, 2012 (GLOBE NEWSWIRE) -- Idenix Pharmaceuticals, Inc. (Nasdaq:IDIX), a biopharmaceutical company engaged in the discovery and development of drugs for the treatment of human viral diseases, today announced that the Company received verbal notice from the U.S. Food and Drug Administration (FDA) that a clinical hold has been placed on IDX19368, the Company's next-generation nucleotide polymerase inhibitor under development for the treatment of hepatitis C virus (HCV) infection. This news follows an announcement that Idenix made on August 16, 2012 related to a partial clinical hold placed on IDX184, the Company's lead nucleotide polymerase inhibitor also under development for the treatment of HCV. The FDA verbally informed Idenix that it placed IDX19368 on clinical hold due to concerns related to the serious cardiac-related adverse events reported for HCV patients treated with BMS-986094, a nucleotide polymerase inhibitor previously under development by Bristol-Myers Squibb Company. To date, no patients have been exposed to IDX19368. "Based on our discussions with the FDA, we understand the clinical hold is a precautionary decision made by the FDA in light of the adverse events seen with BMS-986094," said Ron Renaud, President and CEO. "Both IDX184 and IDX19368 fall into the same broader class of NS5B inhibitors, and share the same active metabolite as BMS-986094. However, there are many attributes of our compounds, particularly the prodrug approach, that we believe favorably differentiate the toxicity profiles from that of BMS-986094. We recently learned that Bristol-Myers Squibb has agreed to share relevant information on BMS-986094 with us and hope this helps us to resolve this issue quickly." As part of the partial clinical hold placed on IDX184, the FDA has requested additional cardiac testing of patients in the ongoing phase IIb clinical trial of IDX184. More than 50 patients have been scheduled for echocardiograms, and the Company is on track to submit these data to the FDA in the coming weeks. To date, echocardiograms have been performed on a small number of these patients, and the results are normal. Idenix's primary concern is patient safety and it will work diligently to expedite this review process and continue its discussions with the FDA with the goal of further advancing its drug candidates, IDX184 and IDX19368, in clinical development.