Pharmasset Announces R7128 Achieves 85% Rapid Virologic Response in a 4-week Combination Study for the Treatment of Chronic H...(bcast. To access the live webcast log on...),Health

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About R7128

R7128 is being developed for the treatment of chronic HCV infection. R7128 is a prodrug of PSI-6130, a cytidine nucleoside analog inhibitor of HCV RNA polymerase. A prodrug is a chemically modified form of a molecule designed to enhance the absorption, distribution and metabolic properties of that molecule. Results from an oral single ascending dose study of PSI-6130 in 24 healthy male volunteers showed that PSI-6130 was generally well tolerated with no serious adverse events in doses up to 3000 mg.

R7128 demonstrated potent, dose-dependent antiviral activity across four patient cohorts (n=40) receiving 750 mg or 1500 mg administered either once- daily or twice-daily for 14 days as monotherapy. The greatest mean decrease in HCV RNA from baseline was demonstrated in the patient cohort that received 1500 mg twice-daily, the highest dose of R7128 administered in the study. These patients demonstrated a mean 2.7 log10 IU/mL (>99%) decrease in HCV RNA. There was no evidence of viral rebound in any dose cohort during the 14 days of dosing.

About Hepatitis C

Hepatitis C is a blood-borne infectious disease of the liver and is a leading cause of chronic liver disease and liver transplants. The WHO estimates that nearly 180 million people worldwide, or approximately 3% of the world's population, are infected with hepatitis C virus
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