US FDA approves Gilead's Viread chronic HBV infection

The US Food and Drug Administration has granted marketing approval for Gilead Sciences' Viread (tenofovir disoproxil fumarate) for the treatment of chronic hepatitis B. The condition is the leading cause of liver cancer worldwide and affects an estimated two million individuals in the USA alone. Viread is now also indicated for the treatment of chronic hepatitis B in adults. Administered as a once-daily tablet, the drug works by blocking HBV DNA polymerase, the enzyme that is necessary for the virus to replicate in liver cells. Viread has been available in the USA as a treatment for HIV infection in adults since 2001. The approval was based on strong data from two ongoing, randomized and double-blind Phase III trials, which compared Viread to Gilead's Hepsera (adefovir dipivoxil) over 48 weeks of treatment.