Ganciclovir is a derivative of acyclovir that was developed to treat human cytomegalovirus (CMV) infection. Initial formulations were given intravenously and were quite toxic. It is used as prophylaxis for life-threatening CMV infections such as pneumonia, retinitis, and colitis in immunocompromised patients. Recently it has been approved as an oral treatment and for long-term use in AIDS patients with CMV infection. The oral formulation seems much less toxic than the intravenously-given kind, thus effective concentrations can be delivered orally.

Please visit Thomas Chi's Antiviral Drug Page for more detailed information
 

REFERENCE:
Flint, et al. Principles of Virology. 2000.
 

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