NCIt definition : The sodium salt form of fomivirsen, an antisense phosphorothioate oligodeoxynucleotide
(ODN) with potent antiviral property. Fomivirsen is a 21-nucleotide ODN complementary
to mRNA of the immediate-early region 2 of human cytomegalovirus (CMV). Hybridization
of this antisense ODN to CMV mRNA prevents RNA transcription from the immediate-early
region 2 gene, thereby inhibiting viral replication. In addition, this agent inhibits
adsorption of CMV into host cells via a sequence-independent mechanism. Overall, fomivirsen
inhibits viral propagation via inhibiting viral replication and viral uptake by host
cells, hence delaying progression of CMV-associated retinitis.;