Entecavir is an antiviral nucleoside analog of 2'-deoxyguanosine and inhibitor of hepatitis B virus (HBV) reverse transcriptase (IC50 = 0.5 nM).1,2 It undergoes phosphorylation by cellular kinases to its active form, entecavir triphosphate.3,2 Entecavir reduces virion DNA in the culture supernatant of HepG2 2.2.15 cells infected with hepatitis B virus (HBV; EC50 = 3.75 nM).1 It reduces serum and hepatic levels of viral DNA in a duckling model of HBV infection when administered at a dose of 1 mg/kg.4 Formulations containing entecavir have been used in the treatment of chronic HBV infection.
1.Innaimo, S.F., Seifer, M., Bisacchi, G.S., et al.Identification of BMS-200475 as a potent and selective inhibitor of hepatitis B virusAntimicrob. Agents Chemother.41(7)1444-1448(1997) 2.Langley, D.R., Walsh, A.W., Baldick, C.J., et al.Inhibition of hepatitis B virus polymerase by entecavirJ. Virol.81(8)3992-4001(2007) 3.Fung, J., Lai, C.-L., Seto, W.-K., et al.Nucleoside/nucleotide analogues in the treatment of chronic hepatitis BJ. Antimicrob. Chemother.66(12)2715-2725(2011) 4.Marion, P.L., Salazar, F.H., Winters, M.A., et al.Potent efficacy of entecavir (BMS-200475) in a duck model of hepatitis B virus replicationAntimicrob. Agents Chemother.46(1)82-88(2002)