Fosfonet sodium (or phosphonoacetate sodium), an organophosphorus compound, was found to be a specific inhibitor of the virus-induced DNA polymerases and thus could inhibit specifically the replication of herpes-viruses.

Fosfonet sodium (or phosphonoacetate sodium), an organophosphorus compound, was found to be a specific inhibitor of the virus-induced DNA polymerases and thus could inhibit specifically the replication of herpes-viruses.

Clevudine (also known as L-FMAU) is a nucleos(t)ide reverse transcriptase inhibitor, which inhibits the DNA synthesis activity of the hepatitis B virus polymerase. The drug was approved in Korea and Philippines and is being marketed under the names Levovir and Revovir. The drug is indicated in patients with chronic hepatitis B virus infection. Upon administration, clevudine is metabolized to the active metabolite, clevudine triphosphate, which is responsible for the inhibition of viral polymerase.