Amdoxovir is a guanosine analogue NRTI prodrug that has good bioavailability. It is deaminated intracellularly by adenosine deaminase to dioxolane guanine (DXG). DXG-triphosphate, the active form of the drug, has greater activity than DAPD-triphosphate. Amdoxovir is currently in phasa II clinical trials.