This study will explore efficacy and safety of Telbivudine in the fifth year of treatment.

Inclusion criteria

• Patient completed Omnibus study and will be available to immediately rollover into this study without discontinuation of study drug.
• Patient was not discontinued from the previous Omnibus study.
• Male or female, adult patients with CHB (HBeAg positive or HBeAg negative).
• Patient is willing and able to provide written informed consent to participate in the study.
• HBV DNA PCR undetectable in recent 12 months.

Exclusion criteria

• Pregnant or breastfeeding, or has plan of pregnant during study period.

• Patient is co-infected with hepatitis C virus (HCV), hepatitis D virus (HDV), r HIV at screening visit.

• Patient needs any anti-HBV treatment combination (add-on therapy) or switch to other anti HBV treatment from Telbivudine at investigator's discretion.

• Patient has any laboratory value abnormality that physicians think he/she may not be suitable to continue the Telbivudine treatment.

• Patient has any clinically significant concurrent severe or unstable disease conditions that physicians think he/she may have any additional risk or not be suitable to participate the study.

• Patient has evidence of renal insufficiency defined as patient requiring dialysis or having an estimated creatinine clearance below 50mL/min, as estimated by the cockcroft-Gault formula.

• Patient is currently abusing alcohol or illicit drugs.

• Patient is enrolled or plans to enroll in another clinical trial of an investigational agent while participating in this study.

• All other treatments for hepatitis B, including commercially available treatments indicated for conditions other than chronic hepatitis B that are being investigated to treat or may have activity against HBV (e.g., ribavirin, famciclovir, ganciclovir, etc.)

• Prolonged use of systemic acyclovir or famciclovir defined as episodic treatment with these agents for periods exceeding 10 days every 3 months, or chronic suppressive therapy.

• Systemic immunomodulators of any type.

• Systemic corticosteroids ( topical and inhaled corticosteroids are permitted).

• Herbal medications known to cause hepatotoxicity (e.g., St. John's Wart, Kava, Jin Bu Huan, Yuzhitang, germander, chaparral, shark cartilage, mistletoe, slim 10, Lipokinetix, etc.).

• Patient has any of the following laboratory values:

  • Hemoglobin < 9 g/dL for menor <8 g/dL for women.
  • Total WBC <1,500/mm3
  • Absolute neutrophil count (ANC)<1,000/mm3
  • Platelet count <30,000/mm3
  • Serum albumin <2.5g/dL
  • Total bilirubin ≥4×ULN
  • Serum creatinine >1.5×ULN