Gilead Sciences to present Viread Phase III clinical trial data

Gilead Sciences, Inc. (Nasdaq:GILD) today announced the presentation of three-year (144-week) open label data from two pivotal Phase III clinical trials, Studies 102 and 103, evaluating the safety and efficacy of once-daily Viread^® (tenofovir disoproxil fumarate) among adult patients with chronic hepatitis B virus (HBV) infection. These data will be presented at the annual meeting of the American Association for the Study of Liver Diseases (The Liver Meeting 2009) being held this week in Boston, October 30-November 3.

These new data show that the majority of patients who received Viread for up to 144 weeks experienced sustained suppression of HBV DNA levels in the blood to below 400 copies/mL (87 percent in Study 102 and 71 percent in Study 103). Additionally, cumulatively over 144 weeks, 8 percent of all patients in Study 103 (HBeAg-positive) experienced “s” antigen (HBsAg) loss, which can contribute to resolution of chronic hepatitis B infection. Notably, no mutations associated with resistance to Viread developed in any patients up to 144 weeks of treatment.

“The development of resistance is a significant challenge for practitioners treating patients with chronic hepatitis B,” said Patrick Marcellin, MD, of Hôpital Beaujon in Clichy, France, and the principal investigator of Study 102. “The robust and comprehensive resistance surveillance in these studies provides important information for the medical community and shows that Viread offers a high barrier to resistance.”

Clinical practice guidelines recommending Viread as a first-line therapy for the treatment of chronic hepatitis B were issued earlier this year by both the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver. The U.S. Food and Drug Administration (FDA) approved Viread for chronic hepatitis B in adults in 2008 based on earlier (48-week) results from Studies 102 and 103, and recently approved the inclusion of 96-week data in the product’s label.

“These data underscore the rationale for Viread’s position as a recommended first-line therapy for chronic hepatitis B infection,” said Jenny Heathcote, MD, of the University of Toronto, Canada, and the principal investigator for Study 103. “In particular, the loss of the hepatitis B ‘s’ antigen in 8 percent of patients, which is associated with resolution of HBV infection, is significant from a clinical perspective.”

Nine additional presentations examining the efficacy of Viread across a variety of patient populations, including treatment-experienced patients, patients new to therapy, patients of Asian descent, pregnant women and patients with decompensated liver disease, also will be presented during The Liver Meeting.