Ganciclovir (BW 759) hydrate, a nucleoside analogue, is an orally active antiviral agent with activity against CMV. Ganciclovir hydrate also has activity in vitro against members of the herpes group and some other DNA viruses. Ganciclovir hydrate inhibits the in vitro replication of human herpes viruses (HSV 1 and 2, CMV) and adenovirus serotypes 1, 2, 4, 6, 8, 10, 19, 22 and 28. Ganciclovir hydrate has an IC50 of 5.2 µM for feline herpesvirus type-1 (FHV-1) and can diffuse into the brain[1][2][3].