Description: Valganciclovir HCl hydrate is the L-valyl ester prodrug of ganciclovir which is an antiviral drug used to treat cytomegalovirus infections. Valganciclovir is an antiviral medication used to treat cytomegalovirus infections. Valganciclovir hydrochloride is a hydrochloride salt of the L-valyl ester of ganciclovir that exists as a mixture of two diastereomers. After administration, these diastereomers are rapidly converted to ganciclovir by hepatic and intestinal esterases. In cytomegalovirus (CMV)-infected cells, ganciclovir is initially phosphorylated to the monophosphate form by viral protein kinase, then it is further phosphorylated via cellular kinases to produce the triphosphate form. This triphosphate form is slowly metabolized intracellularly. The phosphorylation is dependent upon the viral kinase and occurs preferentially in virus-infected cells.