Cidofovir

Cidofovir is activated exclusively by host cell kinases and the active diphosphate, which inhibits DNA polymerases of HSV, CMV, adenovirus, and papillomavirus (HPV). Because phosphorylation does not require viral kinase, cidofovir is active against many acyclovir and ganciclovirresistant strains. Resistance is due to mutations in the DNA polymerase gene. The drug is given intravenously and undergoes renal elimination. Dosage should be adjusted in proportion to creatinine clearance and full hydration maintained. Slow elimination of the active intracellular metabolite permits prolonged dosage intervals and eliminates the permanent venous access used for ganciclovir therapy. Cidofovir is available for IV, intravitreal (injection into the eye’s vitreous humor between the lens and the retina), and topical administration.