Ganciclovir (INN) /ɡænˈsaɪkləvɪər/ or DHPG (9-(1,3-dihydroxy-2-propoxymethyl)guanine, alternative spelling: "Gancyclovir") is an antiviral medication used to treat cytomegalovirus (CMV) infections. Ganciclovir sodium is marketed under the trade names Cytovene and Cymevene (Roche). Ganciclovir for ocular use is marketed under the trade name Vitrasert (Bausch & Lomb). A prodrug form with improved oral bioavailability (valganciclovir) has also been developed.