Abstract
The development of decitabine from its synthesis in 1964 to the submission of a registration file has been described. Although the unique DNA-demethylating capacity of decitabine is known for a long time, its application is under continuing investigation. The use of decitabine in MDS, AML, CML, stem cell transplant, sickle cell anemia and thalassemia looks promising. The epigenetic dose seems lower than the cytotoxic dose. Whereas most drugs have matured after 40 years, decitabine is only at the beginning of a new development phase in epigenesis.