Gilead Sciences has submitted a New Drug Application (NDA) to the FDA for tenofovir alafenamide (TAF) 25mg, an investigational, once-daily treatment for adults with chronic hepatitis B virus (HBV) infection.
TAF is a novel, targeted prodrug of tenofovir that has demonstrated high antiviral efficacy similar to and at a dose less than one-tenth that of Gilead’s Viread (tenofovir disoproxil fumarate, TDF), as well as improvements in surrogate laboratory markers of renal and bone safety as compared to Viread.
“Chronic hepatitis B is a potentially life-threatening disease that impacts millions of people worldwide and often requires prolonged therapy,” said Norbert Bischofberger, Ph.D., executive vice president, R&D, and chief scientific officer, Gilead Sciences. “Given its lower dose, efficacy and safety profile, TAF has the potential to offer patients an improved treatment option that may advance their long-term care of chronic HBV.”
The NDA for TAF is supported by 48-week data from two phase III studies, which met their primary objective of non-inferiority in efficacy compared to Gilead’s Viread among treatment-naïve and treatment-experienced adults with HBeAg-negative and HBeAg-positive chronic HBV. In both studies, changes in renal and bone laboratory safety parameters favored the TAF regimen. Overall, patients receiving TAF experienced a significantly smaller mean percentage decrease from baseline in hip and spine bone mineral density at week 48 compared to patients receiving Viread. Additionally, the overall median change in serum creatinine from baseline to week 48 favored TAF. Rates of discontinuations due to adverse events and the most commonly reported adverse events were similar in patients receiving TAF or Viread.
Gilead plans to submit a regulatory application for TAF in the European Union in the first quarter of 2016.