From my research that it worked well against Epivir resistant virus and it has not develop new resistant stains. Also, viral load had dip to undetectable for 2 people/story (see below link).
Please share your experience, did you fail epivir, length of time on tenofovir, enzyme level and viral load. I am thinking about taking it.

http://www.hepb.org/patients/personal_stories_rudolpho.htm

http://www.hbvadvocate.org/hepatitis/hepB/antiviral_first.html