SAN FRANCISCO--(BUSINESS WIRE)--Gilead Sciences, Inc. (Nasdaq:GILD) today announced new five-year data from the open-label phase of two pivotal Phase 3 clinical trials (Studies 102 and 103) evaluating the efficacy of Viread® (tenofovir disoproxil fumarate) for the treatment of chronic hepatitis B virus (HBV) infection among primarily treatment-naïve patients. Results show that Viread maintains long-term viral suppression of HBV and is associated with a reduction in liver fibrosis and a reversal of cirrhosis. Among patients in both studies, the majority (88 percent) experienced an improvement in overall liver histology. Together, these two studies represent one of the largest datasets evaluating the impact of an oral antiviral therapy on histologic changes and showing a reduction in liver fibrosis. These findings are being presented Monday, November 7 at the 62nd annual meeting of the American Association for the Study of Liver Diseases (The Liver Meeting 2011) in San Francisco.