Gilead Sciences, Inc. (Nasdaq: GILD) announced the presentation
of detailed 48-week data from two phase III pivotal clinical trials, Studies 102 and 103, which evaluate the
safety and efficacy of once-daily Viread® (tenofovir disoproxil fumarate) among adult patients with chronic
hepatitis B virus (HBV) infection. The data are being presented this week in late-breaker sessions at the
annual meeting of the American Association for the Study of Liver Diseases (The Liver Meeting 2007),
currently taking place in Boston, Massachusetts (November 2-6).
Studies 102 and 103 compare Viread to Gilead's Hepsera® (adefovir dipivoxil) among patients with
HBeAg-negative (presumed pre-core mutant) chronic hepatitis B and patients with HBeAg-positive
hepatitis B, respectively. Results from both studies show that patients with chronic hepatitis B who
received Viread for 48 weeks experienced superior efficacy results compared to those who received
Hepsera, as shown by the significantly higher percentage of Viread patients in each trial achieving the
primary efficacy endpoint. Forty-eight week data show that Viread was well-tolerated by patients in both
studies. Gilead announced the topline results from both studies in June 2007.
"The efficacy and tolerability results observed among patients in the Viread arm of the study are
impressive," said Patrick Marcellin, MD, Hôpital Beaujon, Clichy, France, the principal investigator for
Study 102. "Hepsera is commonly considered today's standard of care in chronic hepatitis B therapy and
these data demonstrate that with Viread, it may be possible to achieve an even greater antiviral response and
further improve outcomes for patients."
"Effective antiviral treatment can suppress viral replication and slow or even halt the progression of liver
damage for patients with chronic hepatitis B," said Jenny Heathcote, MD, University of Toronto, Toronto,
Canada, the principal investigator for Study 103. "Viread has a well-established safety profile with over a
million years of patient experience in HIV and this study indicates that it also may be an effective treatment
option for chronic hepatitis B."
Worldwide, an estimated 400 million people are infected with chronic hepatitis B, and it is among the top
ten causes of mortality. The data from Studies 102 and 103 form the basis of Gilead's recent filings of
marketing applications for Viread for the treatment of chronic HBV in the United States and European
Union, which were announced on October 11, 2007. Viread is currently indicated in combination with
other antiretroviral agents for the treatment of HIV-1 infection in adults and is the most-prescribed molecule
in HIV combination therapy in the United States.
"Gilead is committed to playing a leadership role in advancing the treatment of chronic viral hepatitis and
we are excited to make another important contribution to the field with the development of Viread," said
Franck Rousseau, MD, Vice President, Clinical Research, Gilead Sciences. "We believe significant unmet
medical need remains for this serious disease and are working with regulatory authorities in the United
States and European Union to make Viread available for the treatment of HBV at the earliest opportunity."
Study 102
Study 102 (late-breaker presentation #LB2) is a multi-center, randomized, double-blind Phase III clinical
trial evaluating the efficacy, safety and tolerability of Viread compared to Hepsera among patients with
HBeAg-negative presumed pre-core mutant chronic hepatitis B. Study participants were either new to HBV
therapy (treatment-naïve), or had previous experience with lamivudine (treatment-experienced). Three
hundred and seventy-five patients were randomized in a 2:1 ratio to receive either Viread (300 mg once
daily; n=250) or Hepsera (10 mg once daily; n=125) for 48-weeks.
The primary efficacy endpoint was the proportion of patients at Week 48 with a complete response as
defined by serum HBV DNA levels below 400 copies/mL and histologic improvement characterized by at
least a two point reduction in the Knodell necroinflammatory score (a measure of necro-inflammation - an
inflammatory process in the liver including or leading to death of liver cells) with no concurrent worsening
of fibrosis (scarring of liver tissue). Baseline characteristics were similar among patients in both study
arms. At baseline, mean HBV RNA levels were 6.86 log10 c/mL in the Viread group and 6.98 log10 c/mL in
the Hepsera group.
At week 48, 71 percent of patients in the Viread arm had a complete response compared to 49 percent in the
Hepsera arm (p