A prodrug form of adefovir was previously called bis-POM PMEA, with trade names Preveon and Hepsera.

[3][5] Adefovir was invented in the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic by Antonín Holý, and the drug was developed by Gilead Sciences for HIV with the brand name Preveon.

[citation needed] Gilead Sciences discontinued its development for HIV treatment in December 1999, but continued to develop the drug for hepatitis B (HBV), where it is effective with a much lower dose of 10 mg. FDA approval for use in the treatment of hepatitis B was granted on September 20, 2002, and adefovir is sold for this indication under the brand name Hepsera.

[citation needed] Adefovir works by blocking reverse transcriptase, an enzyme crucial for the HBV to reproduce in the body.

The main benefit of adefovir over lamivudine (the first NRTI approved for the treatment of HBV) is that it takes a much longer period of time for the virus to develop resistance to it.