The medications currently approved by the US Food and Drug Administration (FDA) for the initial treatment of chronic hepatitis B include interferon
alfa-2b,
peginterferon alfa-
2a, and the oral nucleoside/nucleotide analogs lamivudine, adefovir dipivoxil, entecavir, and telbivudine, with tenofovir under FDA review for likely approval in 2008.
Each of these drugs has a number of advantages and disadvantages.