- Prior treatment with azacitidine or decitabine for at least 6 courses without response(CR, PR, marrow CR or stable disease with HI according to IWG 2006 criteria) or relapsing after a response. Non responders will be eligible only in the absence of overt progression, ie AML progression (if patients had no AML at onset of azacitidine/decitabine) or doubling of marrow blast percentage between onset of azacitidine/decitabine and screening