San Diego, CA -- February 3, 2009 -- iTherX Pharmaceuticals Inc, a privately held biopharmaceutical company developing novel antiviral products, today announced that it will initiate a Phase 2a clinical study of ITX5061, a potential therapy targeted at inhibiting the entry of the Hepatitis C virus (HCV) into liver cells. The placebo-controlled, randomized trial is a parallel-group dose-response study of the ability of ITX5061 to reduce viral load in treatment-naive and previously treated patients with HCV infection, when ITX5061 is administered as a single agent.

"ITX5061 is an inhibitor of the entry of HCV into liver cells with a potency in the picomolar range, and is equally potent against both genotype 1 and genotype 2 viruses," said Jeffrey McKelvy, Chief Executive Officer of iTherX. "This molecule has exhibited a good safety profile in preclinical studies and in previous clinical studies involving over 250 subjects. Our Phase 2a study represents a first-in-class clinical efficacy study for a small molecule HCV entry inhibitor. We look forward to carrying out further clinical studies to demonstrate the value of ITX5061 in the treatment of this serious illness, which is poorly treated with current therapy."

"Viral entry inhibitors represent a novel and interesting new class of antiviral agents," said John McHutchison, MD, Professor of Medicine at Duke University and Chairman of iTherX Scientific and Clinical Advisory Board. "Such agents could potentially be combined with current standard of care and emerging therapies for the treatment of HCV, since viral entry is involved in both the initiation and maintenance of infection. Moreover, studying combinations of antiviral agents that work through multiple mechanisms of action can be scientifically important, as it enables us to understand the potential clinical applications from both an efficacy and safety point of view. Such combination studies are especially interesting if the compound has a novel mechanism and is highly potent, as ITX5061 is."

The Phase 2a study will enroll approximately 40 patients at three centers in Europe. Primary endpoints for the study will be efficacy as measured by reduction in viral load. Safety and pharmacokinetics will also be assessed.

About iTherX

iTherX Pharmaceuticals is a private pharmaceutical company focused on the discovery, development and commercialization of innovative products for the antiviral marketplace. Additional information on the company can be found at www.itherx.com.