CID 155886088
Imetelstat is a synthetic lipid-conjugated, 13-mer oligonucleotide N3'-P5'-thio-phosphoramidate with potential antineoplastic activity. Complementary to the template region of telomerase (hTR) RNA, imetelstat acts as a competitive enzyme inhibitor that binds and blocks the active site of the enzyme (a telomerase template antagonist), a mechanism of action which differs from that for the antisense oligonucleotide-mediated inhibition of telomerase activity through telomerase mRNA binding. Inhibition of telomerase activity in tumor cells by imetelstat results in telomere shortening, which leads to cell cycle arrest or apoptosis.