Which of the following drugs is a prodrug that after oral administration is conveed to an active agent, penciclovir

Famciclovir It is an ester prodrug of a guanine nucleoside analogue penciclovir. Pharmacokinetics:- It has good oral bioavailability and prolonged intracellular t 1/2 of the active triphosphate metabolite. mech of action:- Like acyclovir, it needs viral thymidine kinase for generation of the active DNA polymerase inhibitor. Uses:- Famciclovir inhibits H. simplex, H. zoster but not acyclovir-resistant strains. Some activity against hepatitis B virus (HBV) has been noted. It is used as an alternative to acyclovir for genital or orolabial herpes and herpes zoster. Early treatment of herpes zoster reduces the duration of post herpetic neuralgia, but not its incidence. Ref:- kd tripathi; pg num:-800