1.5 Combined HBV vaccine and NA therapy in patients with chronic hepatitis B To increase response rate many HBV vaccines has been developed by increase immune epitope or posttranslation modifications (57,58) Combination of Lamivudine with therapeutic HBsAg DNA vaccination led to the persistence of T-cell responses (59). An HBV therapeutic vaccine clinical trial studies showed a decrease of HBV replication in hepatitis B e antigen (HBeAg) positive patients received HBV vaccine and lamivudine combination therapy (60).