Products
Elgravir
Pharmacotherapeutic group
Antiviral drugInternational name
EntecavirDosage form
TabletsAntiviral agent, a guanosine nucleoside analogue with a potent and selective activity against hepatitis B virus (HBV) polymerase.
Entecavir is phosphorylated to the active triphosphate (TP) form, which has an intracellular half-life of 15 hours. Intracellular levels of entecavir triphosphate are directly related to extracellular entecavir concentrations, with no significant accumulation beyond initial plateau levels. By competing with the natural substrate deoxyguanosine triphosphate, entecavir-TP functionally inhibits the 3 activities of the viral polymerase: (1) priming of the HBV polymerase, (2) reverse transcription of the negative strand DNA from the pregenomic mRNA, and (3) synthesis of the positive strand HBV DNA.