At Week 12, all subjects will be administered tenofovir 300 mg QD for an additional 12 weeks, with 4-week supplies of tenofovir. All subjects will return to the clinic at Weeks 13, 14, 16, 20, and 24. Subjects will have safety assessments including symptom-directed physical examinations and safety hematology, biochemistry, and virological studies performed at these visits.