As a result of the current Federal government funding situation, the information on this website may not be up to date or acted upon.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit

Updates regarding government operating status and resumption of normal operations can be found at

NCI Drug Dictionary

  • Resize font
  • Print
  • Email
  • Facebook
  • Twitter
  • Google+
  • Pinterest

The NCI Drug Dictionary contains technical definitions and synonyms for drugs/agents used to treat patients with cancer or conditions related to cancer. Each drug entry includes links to check for clinical trials listed in NCI's List of Cancer Clinical Trials.

A synthetic nucleoside analogue of deoxyadenosine in which the 3' hydroxyl on the ribose moiety is replaced by a hydrogen atom. In vivo, didanosine is converted to the active triphosphate form, which is incorporated into DNA. The absence of the 3' hydroxyl inhibits DNA elongation because phosphodiester bonds cannot be made with the substituted hydrogen. Check for active clinical trials using this agent. (NCI Thesaurus)

Synonym:Didanosine EC
US brand name:Videx
Videx EC
Chemical structure:2',3'-Dideoxyinosine