This study is an open-label extension study for subjects who have completed 14 days of treatment in protocol ACH443-014A and meet all inclusion and exclusion criteria. Elvucitabine treatment (10mg) will begin on Day 1 (Day 15 following completion of protocol ACH443-014A) for all consented subjects in combination with background ART as determined by the principal investigator. Subjects will have clinical and laboratory assessments every 2 weeks for the first 8 weeks and then every 4 weeks to week 48.