Mycophenolate mofetil Recruiting Phase 1 / 2 Trials for Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome / Myelodysplastic Syndrome With Excess Blasts / Chronic Myelomonocytic Leukemia / Acute Lymphoblastic Leukemia in Remission / Recurrent Adult Acute Myeloid Leukemia / Refractory Adult Acute Lymphoblastic Leukemia / High Risk Myelodysplastic Syndrome / CD45-Positive Neoplastic Cells Present / Recurrent Adult Acute Lymphoblastic Leukemia / Acute myeloid leukaemia (in remission) Treatment