This research study is being conducted to compare the safety and effectiveness of the investigational medication, LdT (telbivudine) versus adefovir dipivoxil, a drug approved by the Food and Drug Administration (FDA) for the treatment of hepatitis B infection. The results for patients taking LdT will be compared to results for patients taking adefovir dipivoxil.

Inclusion Criteria:

• Documented compensated chronic hepatitis B defined by clinical history compatible with compensated chronic hepatitis B
• Detectable serum HBsAg at the Screening visit

Other protocol-defined inclusion criteria may apply.

Exclusion Criteria:

• Patient is pregnant or breastfeeding.
• Patient is coinfected with hepatitis C virus (HCV), hepatitis D virus (HDV) or HIV
• Patient previously received lamivudine, adefovir dipivoxil, or an investigational anti-hepatitis B virus (HBV) nucleoside or nucleotide analog at any time
• Patient has received interferon or other immunomodulatory treatment for HBV infection in the 12 months before screening for this study

Other protocol-defined exclusion criteria may apply.