According to the NCI website Cadazuridine is an orally available synthetic nucleoside analog derived from tetrahydrouridine (THU) and cytidine deaminase inhibitor (CDAi), that can potentially be used to prevent the breakdown of cytidines. Check for active clinical trials using this agent.
More Information in English:
Link to Drug Information Portal, a service of the U.S. National Library of Medicine, National Institutes of Health
Link to National Cancer Institute