A hypomethylating agent (or demethylating agent[1]) is a drug that inhibits DNA methylation: the modification of DNA nucleotides by addition of a methyl group.
Because DNA methylation affects cellular function through successive generations of cells without changing the underlying DNA sequence, treatment with a hypomethylating agent is considered a type of epigenetic therapy.
Currently two members of the class, azacitidine and decitabine, are FDA-approved for use in the United States in myelodysplastic syndrome and are being investigated for use in a number of tumors.
[2] Two hypomethylating agents are approved for the treatment of myelodysplastic syndrome by the United States FDA[3][4] DNA methylation is the modification of DNA nucleotides by addition of a methyl group.
Hypomethylating agents decrease the amount of cellular DNA methylation, allowing for tumor suppressor gene expression.