Gilead Sciences has submitted an application to the U.S. Food and Drug Administration (FDA) for approval of an updated version of Viread (tenofovir disoproxil fumarate, or TDF) to treat hepatitis B virus (HBV). The new drug, already approved in a combination treatment for HIV, is called tenofovir alafenamide, or TAF. 

Because TAF better targets cells, a dose less than one-tenth that of TDF is required, thus reducing the chance TAF can cause toxic effects to the body.

The FDA application is backed up by 48-week data from two Phase III studies showing that TAF is “non-inferior” (which essentially means “as good as”) to TDF treating both treatment-naive and treatment-experienced adults with HBeAg-negative and HBeAg-positive hep B. 

Kidney and bone safety tests showed that TAF was the favorable regimen in both studies.   

Gilead intends to submit an application for TAF to treat hep B in the European Union during the first quarter of the year.

To read a Gilead press release on the FDA application, click here.

To read the study abstract, click here.