- Subjects with relapsed or refractory AML, except those with APL (acute promyelocytic leukemia), that are about to receive their initial treatment for first relapse after an initial CR that lasted less than 6 months or for primary refractory AML that have an expected complete response rate ≤20%. The initial diagnosis of AML has to be based on the presence of > 10% blasts in marrow or blood, and the diagnosis of relapsed/refractory AML based on the presence of either > 10% blasts in marrow or blood or 5-10% blasts in either site together with cytopenia (Hb < 10 g/dL, or platelets < 100,000 /uL, or neutrophil count < 1000 /uL).