Valganciclovir, sold under the brand name Valcyte among others, is an antiviral medication used to treat cytomegalovirus (CMV) infection in those with HIV/AIDS or following organ transplant.

[3] Common side effects include abdominal pain, headaches, trouble sleeping, nausea, fever, and low blood cell counts.

[6] Valganciclovir is commonly used for treatment of cytomegalovirus (CMV) retinitis (eye infection may cause blindness) in people who have acquired immunodeficiency syndrome (AIDS).

[2] Other side effects include fever, trouble sleeping, peripheral neuropathy, and retinal detachment.

Its structure is the same as ganciclovir, except for the addition of a L-valyl ester at the 5' end of the incomplete deoxyribose ring.

The L-valyl ester is cleaved by esterases in the intestines and the liver, leaving ganciclovir to be absorbed by the virus-infected cells.

Once incorporated into viral DNA due to its structure similarity to dGTP, chain termination occurs once a single nucleotide is added to the distal hydroxyl group of the incomplete deoxyribose ring of ganciclovir.

However a generic version manufactured by Japanese-owned Indian company Daiichi-Ranbaxy was found by the District Court of New Jersey, USA not to infringe Roche's patent.