3.2 Study design Arm A-entecavir pretreated group: Case vs. histological control study. Arm B-tenofovir pretreated group: randomized case and control study. 3.3. Therapy 3.3.1 Entecavir 0.5 mg daily for at least 3 years. 3.3.2 Tenofovir 300 mg daily for at least 3 years. 3.3.3 Five doses of Engerix-B 20 ug during the last 6 month of NA therapy in case group.